Variation in KRAS/NRAS/BRAF-Mutation Status by Age, Sex, and Race/Ethnicity Among a Large Cohort of Patients with Metastatic Colorectal Cancer (mCRC)

BACKGROUND

Racial/ethnic disparities in metastatic colorectal cancer (mCRC) survival are well documented as is the impact that tumor mutation of KRAS and BRAF has on prognosis. It has been suggested that frequency differences of KRAS- and BRAF-mutated tumors may partially explain this disparity. Demographic differences in mutation frequency are not well established nor whether mutation and microsatellite instability (MSI) differentially impact survival among groups.

METHODS

Using data for 11,117 patients diagnosed with de-novo mCRC from an electronic health record-derived database we estimated adjusted odds ratios (aOR) to characterize the association between demographics and MSI and KRAS/NRAS/BRAF-mutation status. Stratified Cox models were used to identify differences in overall survival (OS), adjusting for treatment and demographics.

RESULTS

Being female, compared to male, (aORKRAS:1.33 (1.23-1.44); aORBRAF:1.84 (1.56-2.16)), and non-Hispanic Black race (NHB), compared to non-Hispanic White (NHW) (aORKRAS:1.62 (1.42-1.85); aORBRAF: 0.55 (0.38-0.77)) were associated with KRAS- or BRAF-mutant tumors. MSI prevalence was similar across race/ethnicity but higher in women. BRAF-mutant tumors were associated with poorer prognosis overall, especially among non-white patients. Among patients who had KRAS/NRAS/BRAF-WT tumors we observed no difference in OS by race or MSI. Among patients with KRAS-mutant tumors, Hispanic patients had more favorable prognosis adjusted hazards ratio (aHR) = 0.76 (0.65-0.89)) than their NHW counterparts. Among those with BRAF-mutant tumors, NHB patients had poorer prognosis than NHW patients (aHR:1.78 (1.08-2.93)).

CONCLUSION

MSI and frequency of KRAS and BRAF mutations differed by demographics. Racial/ethnic disparities in OS differed by mutation. Future studies should explore biological and/or social determinants underlying these differences.

SLCO1B3 and SLCO2B1 genotypes, androgen deprivation therapy, and prostate cancer outcomes: a prospective cohort study and meta-analysis

Solute carrier organic anion (SLCO) transporters (OATP transporters) are involved in cellular uptake of drugs and hormones. Germline variants in SLCO1B3 and SLCO2B1 have been implicated in prostate cancer progression and therapy response, including to androgen deprivation and statin medications, but results have appeared heterogeneous. We conducted a cohort study of five single-nucleotide polymorphisms (SNPs) in SLCO1B3 and SLCO2B1 with prior evidence among 3208 men with prostate cancer who participated in the Health Professionals Follow-up Study or the Physicians' Health Study, following participants prospectively after diagnosis over 32 years (median, 14 years) for development of metastases and cancer-specific death (lethal disease, 382 events). Results were suggestive of, but not conclusive for, associations between some SNPs and lethal disease and differences by androgen deprivation and statin use. All candidate SNPs were associated with SLCO mRNA expression in tumor-adjacent prostate tissue. We also conducted a systematic review and harmonized estimates for a dose-response meta-analysis of all available data, including 9 further studies, for a total of 5598 patients and 1473 clinical events. The A allele of the exonic SNP rs12422149 (14% prevalence), which leads to lower cellular testosterone precursor uptake via SLCO2B1, was associated with lower rates of prostate cancer progression (hazard ratio per A allele, 0.80; 95% confidence interval, 0.69-0.93), with little heterogeneity between studies (I2, 0.27). Collectively, the totality of evidence suggests a strong association between inherited genetic variation in SLCO2B1 and prostate cancer prognosis, with potential clinical use in risk stratification related to androgen deprivation therapy.

Adiposity, Weight Change, and Urinary Melatonin Levels among Men in the Multiethnic Cohort

BACKGROUND

Low levels of 6-sulfatoxymelatonin, the primary urinary metabolite of melatonin, have been linked to cancer and cardiometabolic outcomes in White and female populations.

METHODS

We examined the association between adulthood adiposity and 6-sulfatoxymelatonin levels in a racially and ethnically diverse population. Our study included 4,078 men in the Multiethnic Cohort with adiposity measurements at enrollment (1993-1996) and biomarkers measured in urines collected in 1995 and 2005. Multivariable linear regression models were used to estimate the percent change in 6-sulfatoxymelatonin levels and 95% confidence intervals (CI). Associations were examined separately by racial/ethnic group.

RESULTS

The prevalence of obesity varied by race and ethnicity, from 10% for Japanese American men to 34% for Native Hawaiian men. Compared with men with normal body mass index (BMI), men who were overweight (-7.8%; 95% CI, -11.9 to -3.5%) and obese (-18.1%; 95% CI, -23.2 to -12.6%) had significantly lower 6-sulfatoxymelatonin levels adjusting for potential confounding factors. Increasing weight gain in adulthood was also associated with lower 6-sulfatoxymelatonin (Ptrend < 0.0001). The inverse associations for BMI and weight change were qualitatively similar across racial and ethnic groups.

CONCLUSIONS

Obesity is inversely associated with melatonin in a racially diverse population. This finding is relevant given higher rates of obesity among Black, Native Hawaiian, and Latino men, as well as potential racial and ethnic differences in circadian function.

IMPACT

Melatonin may be a relevant biomarker among obesity-associated malignancies and could shed light on a potential mechanism of cancer disparities.

Association between Outdoor Light at Night and Prostate Cancer in the Health Professionals Follow-up Study

BACKGROUND

Circadian disruption is a potential risk factor for advanced prostate cancer, and light at night (LAN) exposure may disrupt circadian rhythms. We evaluated whether outdoor LAN increases the risk of prostate cancer.

METHODS

We prospectively followed 49,148 participants in the Health Professionals Follow-up Study from 1986 through 2016. We estimated baseline and cumulative time-varying outdoor LAN with ∼1 km2 resolution using data from the US Defense Meteorological Satellite Program's Operational Linescan System, which was assigned to participants' geocoded addresses. Participants reside in all 50 U.S. states and reported a work or home address. We used multivariable Cox models to estimate HRs and 95% confidence intervals (CI) for the association between outdoor LAN and risk of overall (7,175 cases) and fatal (915 cases) prostate cancer adjusting for individual and contextual factors.

RESULTS

There was no association between the interquartile range increase in cumulative LAN and total (HR, 1.02; 95% CI, 0.98-1.06) or fatal (HR, 1.05; 95% CI, 0.96-1.15) prostate cancer in adjusted models. However, there was a positive association between baseline LAN and total prostate cancer among non-movers (HR, 1.06; 95% CI, 1.00-1.14) including among highly screened participants (HR, 1.11; 95% CI, 1.01-1.23).

CONCLUSIONS

There was a suggestive positive association between baseline outdoor LAN and total prostate cancer. Additional studies with different measures of outdoor LAN and in more diverse populations are necessary.

IMPACT

To our knowledge, this is the first longitudinal cohort study exploring the relationship between outdoor LAN and prostate cancer.

Disparities in cause-specific mortality by race and sex among bladder cancer patients from the SEER database

PURPOSE

Previous literature shows that more bladder cancer patients overall die from causes other than the primary malignancy. Given known disparities in bladder cancer outcomes by race and sex, we aimed to characterize differences in cause-specific mortality for bladder cancer patients by these demographics.

METHODS

We identified 215,252 bladder cancer patients diagnosed with bladder cancer from 2000 to 2017 in the SEER 18 database. We calculated cumulative incidence of death from seven causes (bladder cancer, COPD, diabetes, heart disease, external, other cancer, other) to assess differences in cause-specific mortality between race and sex subgroups. We used multivariable Cox proportional hazards regression and Fine-Gray competing risk models to compare risk of bladder cancer-specific mortality between race and sex subgroups overall and stratified by cancer stage.

RESULTS

17% of patients died from bladder cancer (n = 36,923), 30% died from other causes (n = 65,076), and 53% were alive (n = 113,253). Among those who died, the most common cause of death was bladder cancer, followed by other cancer and diseases of the heart. All race-sex subgroups were more likely than white men to die from bladder cancer. Compared to white men, white women (HR: 1.20, 95% CI: 1.17-1.23) and Black women (HR: 1.57, 95% CI: 1.49-1.66) had a higher risk of dying from bladder cancer, overall and stratified by stage.

CONCLUSION

Among bladder cancer patients, death from other causes especially other cancer and heart disease contributed a large proportion of mortality. We found differences in cause-specific mortality by race-sex subgroups, with Black women having a particularly high risk of dying from bladder cancer.

Receipt of Targeted Therapy and Survival Outcomes in Patients With Metastatic Colorectal Cancer

IMPORTANCE

Professional society guidelines recommend treating patients with metastatic colorectal cancer with targeted therapies, including epithelial growth factor receptor (EGFR) inhibitors and vascular endothelial growth factor (VEGF) inhibitors, depending on the presence or absence of certain mutations. Since most studies of first-line targeted therapies have been limited by sample size, there is a need for larger studies using data from routine clinical care.

OBJECTIVES

To identify factors associated with receipt of first-line targeted therapies among patients with metastatic colorectal cancer for whom RAS or BRAF mutation data in the tumor were available and investigate whether targeted therapy is associated with survival.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used deidentified data from an electronic health record-derived database to include patients from 800 sites of patient care across the US who were diagnosed with de novo metastatic colorectal cancer between January 1, 2013, and March 31, 2020 (n = 9134).

MAIN OUTCOMES AND MEASURES

Receipt of first-line targeted therapy, categorized as ever having received EGFR inhibitors, VEGF inhibitors, or neither. The secondary outcome was overall survival.

RESULTS

The study population included 9134 patients. The median age at diagnosis was 62 years (IQR, 53-71 years), 5019 (54.9%) were male, and 5692 (62.3%) were White. The median follow-up period was 15 months. Overall, 713 patients (7.8%) received EGFR inhibitors and 5081 patients (55.6%) received VEGF inhibitors as part of their first-line treatment. Among patients with RAS wild-type (RAS-WT) tumors, 625 patients (15.5%) received EGFR inhibitors and 2053 patients (50.9%) received VEGF inhibitors. In patients with RAS mutant (RAS-Mut) tumors, 50 patients (1.1%) received EGFR inhibitors and 2682 patients (59.7%) received VEGF inhibitors; among those with BRAF-mutant (BRAF-Mut) tumors, 38 patients (6.3%) received EGFR inhibitors and 346 patients (57.2%) received VEGF inhibitors. More than one-third of the patients (36.6%) received neither EGFR inhibitors nor VEGF inhibitors. Compared with patients younger than age 40 years, those aged 80 years or older had significantly lower odds to receive targeted therapies (EGFR or VEGF inhibitors in patients with RAS-WT tumors: adjusted odds ratio [aOR], 0.53; 95% CI, 0.36-0.79; and VEGF inhibitors in patients with RAS-Mut tumors: aOR, 0.62; 95% CI, 0.42-0.90). Improved survival was associated with EGFR inhibitor therapy in patients with RAS-WT tumors (adjusted hazard ratio [aHR], 0.85; 95% CI, 0.74-0.98). Unlike in clinical trials, however, no survival benefit was noted with use of VEGF inhibitors among patients with RAS-WT (aHR, 1.00; 95% CI, 0.91-1.11) or RAS-Mut (aHR, 1.01; 95% CI, 0.93-1.10) tumors.

CONCLUSIONS AND RELEVANCE

The findings of this study showed mixed results on survival benefits associated with targeted therapy. In addition, given that some of the results differed from those of randomized clinical trials, this study highlights the importance of using data originating from routine clinical care.

Cancer burden in women with HIV on Medicaid: A nationwide analysis

BACKGROUND

Cancer is the leading cause of death in people living with HIV. In the United States, nearly 1 in 4 people living with HIV are women, more than half of whom rely on Medicaid for healthcare coverage.

OBJECTIVE

The objective of this study is to evaluate the cancer burden of women living with HIV on Medicaid.

DESIGN

We conducted a cross-sectional study of women 18-64 years of age enrolled in Medicaid during 2012, using data from Medicaid Analytic eXtract files.

METHODS

Using International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes, we identified women living with HIV (n = 72,508) and women without HIV (n = 17,353,963), flagging the presence of 15 types of cancer and differentiating between AIDS-defining cancers and non-AIDS-defining cancers. We obtained adjusted prevalence ratios and 95% confidence intervals for each cancer and for all cancers combined, using multivariable log-binomial models, and additionally stratifying by age and race/ethnicity.

RESULTS

The highest adjusted prevalence ratios were observed for Kaposi's sarcoma (81.79 (95% confidence interval: 57.11-117.22)) and non-Hodgkin's lymphoma (27.69 (21.67-35.39)). The adjusted prevalence ratios for anal and cervical cancer, both of which were human papillomavirus-associated cancers, were 19.31 (17.33-21.51) and 4.20 (3.90-4.52), respectively. Among women living with HIV, the adjusted prevalence ratio for all cancer types combined was about two-fold higher (1.99 (1.86-2.14)) in women 45-64 years of age than in women 18-44 years of age. For non-AIDS-defining cancers but not for AIDS-defining cancers, the adjusted prevalence ratios were higher in older than in younger women. There was no significant difference in the adjusted prevalence ratios for all cancer types combined in the race/ethnicity-stratified analyses of the women living with HIV cohort. However, in cancer type-specific sub-analyses, differences in adjusted prevalence ratios between Hispanic versus non-Hispanic women were observed. For example, the adjusted prevalence ratio for Hispanic women for non-Hodgkin's lymphoma was 2.00 (1.30-3.07) and 0.73 (0.58-0.92), respectively, for breast cancer.

CONCLUSION

Compared to their counterparts without HIV, women living with HIV on Medicaid have excess prevalence of cervical and anal cancers, both of which are human papillomavirus related, as well as Kaposi's sarcoma and lymphoma. Older age is also associated with increased burden of non-AIDS-defining cancers in women living with HIV. Our findings emphasize the need for not only cancer screening among women living with HIV but also for efforts to increase human papillomavirus vaccination among all eligible individuals.

Prostate Cancer Screening and Young Black Men: Can Early Communication Avoid Later Health Disparities?

This study aims to determine if younger men, across racial and ethnic groups, discussed the benefits/risks/harms of PSA screening with health care professionals. Publicly available data were obtained from the Health Information National Trends Survey https://hints.cancer.gov/ in March 2019. Cross-sectional analysis of 518 men between the ages of 18 and 49 years from men who completed the survey between October 2011 and February 2012 (HINTS cycle 4) was performed. We used logistic regression to evaluate the association between race/ethnicity and discussions around PSA. Less than 10% of the participants reported a prior PSA; Black and Hispanic men were more likely compared with White men. Compared with White men, Black and other race men reported receiving less communications from some doctors recommending PSA screening (OR_black: 0.16, 95% CI_black: 0.07-0.38; OR_other: 0.10, 95% CI_other: 0.04-0.25), and that no one is sure PSA testing saves lives (OR_black: 0.49, 95% CI_black: 0.04-6.91; OR_other: 0.17, 95% CI_other: 0.06-0.48). Minority men, while more likely to have had a PSA, were less likely to be told of the harms and benefits of PSA testing, compared with White men. Increasing communication surrounding screening advantages and disadvantages between providers and patients can increase awareness and knowledge among younger men. In a post-COVID-19 environment, communication regarding the return to preventative screenings within vulnerable populations is an important message to convey. Research shows preventive screenings have dropped across all population groups due to the pandemic yet the decline disproportionately affects Black and other minority men.

Sociodemographic and clinical factors associated with receipt of biomarker testing in patients with metastatic colorectal cancer

BACKGROUND

Standard clinical practice and national guidelines dictate somatic testing of metastatic colorectal cancer (mCRC) tumors to guide appropriate therapy; however, previous studies suggest that not all patients are tested. The objective of this study was to investigate potential differences in testing for mCRC by demographic and clinical factors.

METHODS

We performed a retrospective review of de-identified patient data derived from electronic health records (EHRs) of 25,469 patients diagnosed with mCRC between the years 2013 and 2020. Our outcome was a receipt of the following tests: (a) biomarker testing (BRAF, KRAS, NRAS, MMR/MSI) and (b) next-generation sequencing (NGS). We interrogated our data using the machine-learning algorithm Classification and Regression Tree (CART), a unique approach to identifying combinations of, rather than individual demographic and clinical characteristics associated with receipt of testing.

RESULTS

A total of 25,469 patients were identified with mCRC. Of these, 21,133 (83%) received either biomarker testing only (n = 12,485) or any testing (biomarker + NGS) (n = 8648). The proportion of patients who received any testing increased over calendar time for all age, race, and sex categories. Receipt of any testing was highest (90%) among younger and patients with better performance status, and there was no difference in receipt of any testing by race. The highest percentage of NGS testing was among those with better performance status, <70 years old, commercial or other governmental program payers, and low comorbidity burden; however, those who were Black or Hispanic had a lower prevalence of NGS testing than those who were White.

CONCLUSIONS AND RELEVANCE

Considerable variations exist in somatic biomarker testing across subgroups of the population. Identification of genomic alterations can aid in determining targeted treatment and improving clinical outcomes; therefore, equitable use of these testing strategies, particularly NGS, is necessary.

A nationwide analysis of pancreatic cancer trial enrollment reveals disparities and participation problems

BACKGROUND

Our research group recently surveyed the clinical trial landscape in pancreatic adenocarcinoma and identified 430 active trials. These represent an opportunity to expand treatment options for patients with pancreatic adenocarcinoma. Our primary objective was to detail clinical trial participation among patients with pancreatic adenocarcinoma. Our secondary objective was to evaluate survival.

METHODS

We queried the National Cancer Database (2004-2016) for patients with pancreatic adenocarcinoma. Patients were stratified by trial participation: clinical trial or non-trial. Multivariable logistic regression was used to identify variables associated with trial participation. The Kaplan-Meier method and multivariable Cox hazards regression were used to analyze survival.

RESULTS

In total, 261,483 patients were included: 1,110 (0.4%) were enrolled in a clinical trial. A total of 57 Black patients participated in a clinical trial (0.19% of Black patients). This was lower compared to White patients (n = 955, 0.49% of White patients, P < .001). After adjusting for demographic and clinical factors, Black patients were less likely to be enrolled in a clinical trial (odds ratio = 0.387, P < .001). Patients treated at nonacademic medical centers were less likely to be in a clinical trial. Trial participation was associated with an increased median survival relative to non-trial patients (stage IV: 9.0 vs 3.8 months, P < .001), and this association remained on multivariable regression (hazard ratio = 0.779, P < .001).

CONCLUSION

Fewer than 1% of patients with pancreatic adenocarcinoma participated in a clinical trial. There are racial and sociodemographic disparities in clinical trial enrollment. An association was observed between clinical trial participants and prolonged survival.

Abstract 1438: Organic anion transporter(SLCO)genotype and prostate cancer progression: Prospective cohort study and meta-analysis

Background: Organic anion-transporting polypeptides, encoded by SLCO genes, have multiple substrates, including androgens. Genotype and protein levels moderate the uptake of androgens into prostate cells, a process competitively inhibited in vitro by statin medications. Single-nucleotide polymorphisms (SNPs) in SLCO2B1 influence SLCO1B2 expression and efficacy of androgen uptake in vitro.

Methods: Among men of self-reported European ancestry diagnosed with prostate cancer during prospective follow-up of the Health Professionals Follow-up Study (HPFS, diagnosed 1986-2017) and the Physicians’ Health Study (PHS, 1982-2010) combined, we evaluated four SLCO2B1 SNPs identified in prior studies and time from diagnosis to lethal disease (metastases/prostate cancer-specific death), adjusting for age, calendar year of diagnosis, and principal components of genetic variation to account for local ancestry. We also conducted a systematic review and harmonized allele coding in prior studies for a two-stage dose-response meta-analysis with additive allele coding.

Results: Of the 3208 men in the prospective cohort study, 96% were diagnosed with clinically localized (T1/T2) prostate cancer. Most were treated with radical prostatectomy (47%) or radiation (36%); 33% ever received androgen deprivation therapy (ADT). Over up to 32 years of follow-up (median, 14.4 years), 382 lethal events occurred. The intronic SNP rs1077858 had the strongest association with lethal disease (hazard ratio [HR] per minor allele 1.14, 95% confidence interval [CI] 0.98-1.33). Data were suggestive of potential differences for the four SNPs by use of statins and ADT but were not conclusive. The systematic review identified 2 additional population-based studies of primary disease and 4 hospital-based studies of advanced disease, none of which studied effect modification by statins or ADT. Among these 2377 men, 1088 events of recurrence, metastasis, or prostate cancer death occurred. In a meta-analysis of all 7 studies, the genotype of the exonic SNP rs12422149 (minor allele frequency 15%) that results in lower androgen uptake was associated with better outcomes (HR per minor allele 0.80, 95% CI 0.69-0.93), with little between-study heterogeneity (I2 0.27). For the intronic SNP rs1077858, the genotype with higher SLCO2B1 mRNA expression was associated with worse outcomes (HR per minor allele 1.14, 95% CI 0.99-1.31, 3 studies with I2 0.68).

Conclusion: These results are compatible with the hypothesis that inherited genetic variation in SLCO2B1 influences androgen uptake and prostate cancer prognosis. These and other genetic variants, together with clinical features, may have potential utility as predictive biomarkers for identifying men with prostate cancer who might benefit from early therapy beyond ADT. Whether adjuvant statin therapy could mitigate the inherited risk requires further study.

Citation Format: Konrad H. Stopsack, Harisha Rajanala, Anna Plym, Jane B. Vaselkiv, Konstantina Matsoukas, Ericka M. Ebot, Sarah C. Markt, Kathryn L. Penney, Gwo-Shu M. Lee, Lorelei A. Mucci, Philip W. Kantoff. Organic anion transporter(SLCO)genotype and prostate cancer progression: Prospective cohort study and meta-analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1438.

Abstract 4126: Treatment and survival of patients with de novo metastatic colorectal cancer (mCRC) rested for KRAS, NRAS or BRAF mutations

Study Purpose: Molecular profiling of RAS (KRAS, NRAS) and BRAF mutations in mCRC is recommended by national guidelines to inform targeted treatment. The purpose of this study was to determine whether results of genomic testing are associated with receipt of targeted therapy (i.e. VEGFi and EGFRi), and whether receipt of first-line targeted therapy is associated with survival among patients with mCRC.

Methods: Using the nationwide de-identified electronic health record-derived Flatiron Health database, we included 10,168 patients with de novo mCRC diagnosed between 2013-2020 and tested for at least one of the above biomarkers at any time. We used multivariable Cox proportional hazards regression models, beginning follow-up at date of metastatic diagnosis and continued until death or end of follow-up, adjusted for age, sex, race/ethnicity, mutation status (mutant vs. wild type (WT)), tumor site (colon vs. rectum), mismatch repair (MMR), comorbidities, ECOG status, payer type, and first-line (1L) treatment, to investigate the associations between: 1) mutation status and 1L treatment; and 2) 1L treatment and overall survival.

Results: Overall, 9.5% did not have documented 1L treatment. Among patients with 1L treatment documented (n=9,202), the most common were FOLFOX+VEGFi (36.3%), followed by FOLFOX alone (15.8%), single-agent capecitabine (7.2%), and FOLFIRI+VEGFi (5.0%). After adjusting for treatment, patients with KRAS, NRAS, and BRAF mutant tumors had worse survival than those WT for all three: (HR: 1.32, 95% confidence interval: 1.23-1.42), (HR: 1.23, 95% CI: 1.04-1.47), and (HR: 1.77, 95% CI: 1.57-2.00), respectively. Of patients with RAS mutations, 59.8% received VEGFi, regardless of chemotherapy backbone. Contrary to outcomes reported from clinical trials, we observed similar survival in patients treated with VEGFi, compared to those without (HR: 1.03, (0.95-1.12)). Among patients with RAS WT tumors, 51.6% received VEGFi, but had no survival benefits (HR:1.06 (0.96-1.17)). About 1% of patients RAS mutant and 15.9% of RAS WT tumors received EGFRi regardless of chemotherapy backbone, and experienced better survival than those treated with VEGFi (HR: 0.88 (0.77-1.00). We observed no differences in survival by treatment among those with BRAF mutations.

Conclusions: Treatment with VEGFi was common. However, contrary to survival data from clinical trials, which exclude vulnerable populations, patients treated with VEGFi did not experience survival benefits, highlighting the importance of examining survival outcomes in routine clinical care. In patients with RAS WT tumors, treatment with EGFRi was associated with improved survival compared with those treated with VEGFi. Future studies should incorporate tumor sidedness and contraindications to determine appropriateness of treatment with VEGFi or EGFRi in patients with mCRC.

Citation Format: Ben D. Booker, Sarah C. Markt, Fredrick R. Schumacher, Johnie Rose, Greg S. Cooper, J Eva Selfridge, Siran M. Koroukian. Treatment and survival of patients with de novo metastatic colorectal cancer (mCRC) rested for KRAS, NRAS or BRAF mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4126.

Thromboembolism (TE) and association with survival in patients (pts) with melanoma receiving chemo– or immunotherapy

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Background: Emerging reports suggest high rates of venous thromboembolism (VTE) and arterial thromboembolism (ATE) with immune checkpoint inhibitors (ICI) in pts with melanoma, but it is unclear whether these are truly increased compared to older systemic therapy approaches. We assessed the incidence of TE in melanoma pts on ICI, cytokine therapy (CY), and chemotherapy (chemo), and evaluated its impact on survival. Methods: We conducted a cohort study using the SEER-Medicare database to evaluate rates of TE in pts with melanoma treated from 2008-2019 with ICI (ipilimumab, nivolumab, pembrolizumab), CY (IL2, IFN), and/or chemo (antineoplastic agents, BRAF/MEK inhibitors) within two years of treatment initiation. TE including VTE events of deep venous thrombosis, pulmonary embolism, and ATE of MI, ischemic stroke, and transient ischemic attack were identified by at least two outpatient claims or one inpatient claim. Overall survival (OS) from treatment start was analyzed by time-varying Cox analysis. Results: The cohort comprised 13,124 pts with median age 75 (24-101) years and 68% male. Of these, 14.8% received ICI, 48.9% chemo, 1.7% CY, 31.8% chemo+ICI, and 2.8% chemo+CY. At treatment start, comorbidities included 72% of pts with hypertension, 33% cerebrovascular disease, 17% atrial fibrillation, 7.3% history of VTE, and 13.0% history of ATE. Overall, 11.4% were on anticoagulation and 5.2% on antiplatelet agents. Incidence rates of ATE and VTE after treatment start are shown (Table). VTE was highest at 3 months after starting therapy with 19.6 events per 100 person-years in those receiving chemo+ICI, 17.1 events with chemo, 15.4 events with ICI, 10.1 events with chemo+CY, and 7.7 events with CY. In multivariable analysis, VTE and ATE were associated with worse OS compared to patients without (HR 2.77 [95%CI, 2.50-3.08], and HR 2.53 [95%CI, 2.23-2.86], respectively). Conclusions: Systemic therapy with ICI and chemo, especially when exposed to both sequentially or concurrently, demonstrates a high incidence of TE in pts with melanoma. TE is associated with substantial worsening of survival. TE rates are not substantially increased with ICI in comparison to chemo. Further studies are needed to identify benefit of thromboprophylaxis.[Table: see text]

Weight Tracking as a Novel Prognostic Marker After Pancreatectomy

BACKGROUND

Objective measures of post-pancreatectomy weight change for pancreatic ductal adenocarcinoma (PDAC) have not been extensively studied for long-term outcomes. We used weight measurements in our institutional medical record to analyze trends in post-pancreatectomy weight and determine the association with disease status.

METHODS

Pancreatectomies for PDAC (n = 315) and benign indications (n = 111) were identified. Preoperative baseline, minimum postoperative (Min #1), and subsequent postoperative maximum (Max) weights were abstracted. Multivariable Cox hazards regression was conducted to analyze the association between weight change and survival.

RESULTS

Median weight loss postoperatively in each group was > 20 lbs. PDAC patients gained 10 lbs after Min #1 compared to 15 lbs in the benign cohort (p < 0.001). Few patients returned to their preoperative weight (29.8% PDAC vs. 40.5% benign, p = 0.04). Patients with early PDAC recurrence (< 13 months) lost more weight (18.0% vs. 13.3% vs. 10.9%, p < 0.001) and gained less weight (2.1% vs. 12.0% vs. 7.9%, p < 0.001) compared with those with late cancer recurrence (≥ 13 months) or no evidence of active disease, respectively. PDAC patients lost 11.2 lbs in the year preceding recurrence diagnosis. Weight loss was not associated with survival; however, weight gain was associated with improved survival.

CONCLUSIONS

Resections for PDAC are complicated by a similar degree of weight loss as patients with benign disease, and there is no association with survival. However, failure to gain weight is especially ominous. Weight loss after weight recovery foreshadows disease recurrence. These data suggest that rigorous weight tracking is an untapped surveillance strategy in patients with PDAC.

Harm-to-Benefit of Three Decades of Prostate Cancer Screening in Black Men

BACKGROUND

Prostate-specific antigen screening has profoundly affected the epidemiology of prostate cancer in the United States. Persistent racial disparities in outcomes for Black men warrant re-examination of the harms of screening relative to its cancer-specific mortality benefits in this population.

METHODS

We estimated overdiagnoses and overtreatment of prostate cancer for men of all races and for Black men 50 to 84 years of age until 2016, the most recent year with treatment data available, using excess incidence relative to 1986 based on the Surveillance, Epidemiology, and End Results registry and U.S. Census data as well as an established microsimulation model of prostate cancer natural history. Combining estimates with plausible mortality benefit, we calculated numbers needed to diagnose (NND) and treat (NNT) to prevent one prostate cancer death.

RESULTS

For men of all races, we estimated 1.5 to 1.9 million (range between estimation approaches) overdiagnosed and 0.9 to 1.5 million overtreated prostate cancers by 2016. Assuming that half of the 270,000 prostate cancer deaths avoided by 2016 were attributable to screening, the NND and the NNT would be 11 to 14 and 7 to 11 for men of all races and 8 to 12 and 5 to 9 for Black men, respectively. Alternative estimates incorporating a lag between incidence and mortality resulted in a NND and a NNT for Black men that reached well into the low single digits.

CONCLUSIONS

Complementary approaches to quantifying overdiagnosis indicate a harm-benefit tradeoff of prostate-specific antigen screening that is more favorable for Black men than for men of all races considered together. Our findings highlight the need to account for the increased value of screening in Black men in clinical guidelines. (Funded by the Patient-Centered Outcomes Research Institute, the National Cancer Institute, the Bristol Myers Squibb Foundation, and the Damon Runyon Cancer Research Foundation.).

Racial Disparities in Prostate Cancer: Evaluation of Diet, Lifestyle, Family History, and Screening Patterns

BACKGROUND

Racial disparities in prostate cancer incidence and mortality rates are considerable. We previously found in the Health Professionals Follow-up Study (HPFS) that African-American men had an 80% higher prostate cancer risk than White men. With 21 additional years of follow-up and four-fold increase in cases, we undertook a contemporary analysis of racial differences in prostate cancer incidence and mortality in HPFS.

METHODS

For 47,679 men, we estimated HRs and 95% confidence intervals (CI) for the association between race and risk of prostate cancer through 2016 using Cox proportional hazards regression. Multivariable models (mHR) were adjusted for lifestyle, diet, family history, and PSA screening collected on biennial questionnaires.

RESULTS

6,909 prostate cancer cases were diagnosed in White, 89 in African-American, and 90 in Asian-American men. African-Americans had higher prostate cancer incidence (mHR = 1.31; 95% CI, 1.06-1.62) and mortality (mHR = 1.67; 95% CI, 1.00-2.78), and lower PSA screening prevalence than White men. The excess risk was greater in the pre-PSA screening era (HR = 1.68; 95% CI, 1.14-2.48) than the PSA screening era (HR = 1.20; 95% CI, 0.93-1.56). Asian-Americans had lower prostate cancer risk (mHR = 0.74; 95% CI, 0.60-0.92), but similar risk of fatal disease compared with white men.

CONCLUSIONS

Racial differences in prostate cancer incidence and mortality in HPFS are not fully explained by differences in lifestyle, diet, family history, or PSA screening.

IMPACT

Additional research is necessary to address the disproportionately higher rates of prostate cancer in African-American men.

Weight loss during neoadjuvant therapy for pancreatic cancer does not predict poor outcomes

BACKGROUND

Weight changes during neoadjuvant chemotherapy (NAC) for pancreatic cancer (PDAC) are not well studied. We hypothesized that weight loss may predict poor outcomes.

METHODS

Weight change from NAC initiation to pancreatectomy was grouped: gain (≥5%), stable, and loss (≥5%). Pathologic, postoperative, and survival outcomes were compared.

RESULTS

95 patients were included: 31.6% lost weight, 58.9% maintained weight, and 9.5% gained weight. There were no differences in chemotherapeutic regimens. Median recurrence-free survival (RFS) and overall survival (OS) were similar between patients with stable weight and those who lost weight (RFS: 9.6vs14.0months; OS: 25.8vs26.7months). Among those who gained weight, RFS (29.5months) and OS (38.4months) were greater relative to the other weight categories. On multivariable regression, weight gain was associated with improved RFS compared to loss (HR = 0.16).

CONCLUSION

Most patients maintain or lose weight during NAC, and weight loss does not predict poor outcomes. Weight gain may predict improved RFS.

Excess cancer prevalence in men with HIV: A nationwide analysis of Medicaid data

BACKGROUND

Cancer is one of the most common comorbidities in men living with HIV (MLWH). However, little is known about the MLWH subgroups with the highest cancer burden to which cancer prevention efforts should be targeted. Because Medicaid is the most important source of insurance for MLWH, we evaluated the excess cancer prevalence in MLWH on Medicaid relative to their non-HIV counterparts.

METHODS

In this cross-sectional study using 2012 Medicaid Analytic eXtract data nationwide, we flagged the presence of HIV, 13 types of cancer, symptomatic HIV, and viral coinfections using codes from the International Classification of Diseases, Ninth Revision, Clinical Modification. The study population included individuals administratively noted to be of male sex (men), aged 18 to 64 years, with (n = 82,495) or without (n = 7,302,523) HIV. We developed log-binomial models with cancer as the outcome stratified by symptomatic status, age, and race/ethnicity.

RESULTS

Cancer prevalence was higher in MLWH than in men without HIV (adjusted prevalence ratio [APR], 1.84; 95% confidence interval [CI], 1.78-1.90) and was higher among those with symptomatic HIV (APR, 2.74; 95% CI, 2.52-2.97) than among those with asymptomatic HIV (APR, 1.73; 95% CI, 1.67-1.79). The highest APRs were observed for anal cancer in younger men, both in the symptomatic and asymptomatic groups: APR, 312.97; 95% CI, 210.27-465.84, and APR, 482.26; 95% CI, 390.67-595.32, respectively. In race/ethnicity strata, the highest APRs were among Hispanic men for anal cancer (APR, 198.53; 95% CI, 144.54-272.68) and for lymphoma (APR, 9.10; 95% CI, 7.80-10.63).

CONCLUSIONS

Given the Medicaid program's role in insuring MLWH, the current findings highlight the importance of the program's efforts to promote healthy behaviors and vaccination against human papillomavirus in all children and adolescents and to provide individualized cancer screening for MLWH.

Urinary 6-sulfatoxymelatonin Levels and Prostate Cancer Risk among Men in the Multiethnic Cohort

BACKGROUND

The circadian hormone melatonin has anticancer properties, and prior studies suggest a positive association between low melatonin and prostate cancer risk. The purpose of this study was to examine urinary melatonin levels and prostate cancer in a racially/ethnically diverse cohort.

METHODS

We conducted a nested case-control study, including 1,263 prostate cancer cases and 2,346 controls, sampled from participants in the Multiethnic Cohort Study with prediagnostic urine samples assayed for 6-sulfatoxymelatonin, the primary melatonin metabolite. Conditional logistic regression was used to examine the association between melatonin levels and the development of prostate cancer outcomes (all incident cases, advanced, lethal, high-grade, and aggressive), overall and by race/ethnicity.

RESULTS

Among 1,263 cases, 135 were advanced stage, 101 were lethal cases, and 282 were high-grade disease. Median melatonin levels were similar in controls [17.12 ng/mL; interquartile range (IQR), 19.78] and cases (17.93 ng/mL; IQR, 19.76), and we found no significant association between urinary melatonin levels and prostate cancer risk overall or in any clinical or racial subgroup.

CONCLUSIONS

In this diverse cohort, there was no significant association between melatonin and any prostate cancer outcome, nor were there any differences by racial/ethnic group.

IMPACT

These results do not support a strong association between melatonin levels and risk of prostate cancer.

Characterization of fungal mycobiome in bladder cancer

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Background: Bacterial dysbiosis accompanies carcinogenesis in malignancies such as colon, breast and pancreatic cancer. However, the role of fungal mycobiome has not been evaluated in bladder cancer. With the sexual dimorphism that exists within bladder cancer (Bca) prevalence and survival, our study aims to characterize fungal mycobiome composition in Bca. Methods: This is a single site, non-randomized, prospective study of patients with the diagnosis of muscle invasive bladder cancer (MIBC) undergoing cystectomy from September 2020 to May 2021. Stool samples were collected during surgery using aseptic technique. We utilized the ITS1 region from DNA sample extracts, which was amplified in triplicate using primers with high specificity for ascomycete fungi (fluorescently-labeled forward primer ITS1F (CTTGGTCATTTAGAGGAAGTAA) and unlabeled reverse primer ITS2 (GCTGCGTTCTTCATCGATGC). Fungal PCR products were separated on the SCE 9610 capillary DNA sequencer (Spectrumedix LLC, State College, PA) using GenoSpectrum software to convert fluorescent output into electropherograms. Hierarchical clustering by Bray-Curtis distance was performed using hclust2. Mean normalized abundance for each amplicon was calculated from the three PCR replicates of each sample, excluding means below 1%. Results: A total of 29 patients (17 males and 12 females) were enrolled. The median (IQR) age was 74 yo (63-77), males, and 68.5 yo (58-78), females. Per figure 1, Saccharomycecales dominated the fungal community at order level with mean relative abundance of 36.35% females, and 21.20%, males. (Figure 1D) Tremellales was the second most notable order, composing 8.22% and 5.13% of male and female samples. There were no differences seen in alpha and beta diversity (Figure 1C) (Figure 1A, C), notable differences were seen across orders. The greatest difference between sexes in LDA( M:F) were noted in Saccharomycecales (log change -4.686, p=0.001/ padj= 0.01), Tremellales (log change 5.119, p=0.001/padj= 0.01), and Sporidiobolales (log change 4.839, p=0.001 padj= 0.03). (Figure 1B). Female bladder cancer patients demonstrating an increase abundance of Saccharomycecale. When assessing differences in fungal composition in patients with history of neoadjuvant therapy( NAC) (receipt vs none), patients with history of NAC exhibited a 3.48 increase in Saccharomycecale (padj= 0.015 ), 4.81 increase Tremalles (padj= 0.009) and 4.37 increase Pleosporales(padj= 0.009) . Conclusions: Mycobiome is an integral part of gut microbiota, with fungal elements relatively poorly studied. Nevertheless, the association between fungal dysbiosis and carcinogenesis across multiple cancers exists. Our study is the first to characterize fungal profile in bladder cancer patients, stratified by sex and receipt of NAC, with results highlighting key fungal players: Saccharomycecale, Tremallales, Pleosoporales.

Characterization and functional analysis of microbiome in bladder cancer

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Background: The role of microbiome in genitourinary cancer is an emerging field, with evidence implicating the important role of microbiome as causative factors or cofactors in tumorigenesis and drug metabolism. Our study aims to characterize healthy and bladder cancer enterotypes in the gut and identify functional alterations through the use of metagenomics data. Methods: After prospective collection of 29 rectal swab samples of bladder cancer (BCa) patients undergoing cystectomy, and 32 healthy volunteers, we perform 16S rRNA amplicon sequencing on 61 samples (29 with bladder cancer, 32 without cancer). Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was applied to infer functional categories associated with taxonomic composition. The p values were adjusted using the false discovery rate. The a- and b-diversity analyses were performed using QIIME. The Mann-Whitney U test was employed to evaluate the statistical significance of b-diversity distances within and between groups of interest. Results: Across all the bladder cancer stool samples, estimation of relative abundance revealed of the five most dominant bacterial populations was Bacteroidales ( 46.21%), Clostridiales ( 32.29%), Burkholderiales (9.07%), Erysipelotrichales (3.20%) and Lactobacillales ( 2.20%). In contrast, healthy controls exhibited an increased relative abundance of Enterobacteriales ( 10.75% vs 0.52%) and Pseudomonadales (8.33% vs 0.18%) as compared to tumor samples. The microbial diversity differences between Bca and normal samples showed no differences across alpha diversity metrics (Shannon diversity p>0.05) as compared to normal tissue. However, there was significant difference in clustering of organisms as determined by principal coordinate analysis ( PCoA) ordination of unweighted UniFrac Distances, (p=0.002). Furthermore, upon stratification of patients on smoking status (all healthy=nonsmokers), clustering persisted, albeit non smokers with bladder cancer displayed an intermediate across PCoA. Bca samples exhibited higher LDA score Campylobacterales (log change 8.0, p<0.001, padj <0.001) ,Fusobacteriales (log change 6.11, p<0.001/ padj<0.01), Epysipelotrichales (log 2.55, p<0.001/ padj <0.001 ), Actinomycetales (log change 1.86, p=0.001/ padj<0.001), Verrucomicrobiales (log change 1.78, p=0.017/padj=0.031) and Enterobacteriales (log change -1.54,p=0.017/ padj= 0.132). Conclusions: In conclusion, our study provides preliminary evidence that the GI microbiota is different in bladder cancer patients. Collectively, our study highlights distinct microbial overexpression of Campylobacter and Fusobacterium in Bca cohort not previously reported, both implicated in tumorigenesis, and could serve as a target that could be modulated to enhance treatment response.

Racial and Ethnic Disparities in Prostate Cancer Outcomes in the Veterans Affairs Health Care System

IMPORTANCE

Prostate cancer (PCa) disproportionately affects African American men, but research evaluating the extent of racial and ethnic disparities across the PCa continuum in equal-access settings remains limited at the national level. The US Department of Veterans Affairs (VA) Veterans Hospital Administration health care system offers a setting of relatively equal access to care in which to assess racial and ethnic disparities in self-identified African American (or Black) veterans and White veterans.

OBJECTIVE

To determine the extent of racial and ethnic disparities in the incidence of PCa, clinical stage, and outcomes between African American patients and White patients who received a diagnosis or were treated at a VA hospital.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included 7 889 984 veterans undergoing routine care in VA hospitals nationwide from 2005 through 2019 (incidence cohort). The age-adjusted incidence of localized and de novo metastatic PCa was estimated. Treatment response was evaluated, and PCa-specific outcomes were compared between African American veterans and White veterans. Residual disparity in PCa outcome, defined as the leftover racial and ethnic disparity in the outcomes despite equal response to treatment, was estimated.

EXPOSURES

Self-identified African American (or Black) and White race and ethnicity.

MAIN OUTCOMES AND MEASURES

Time to distant metastasis following PCa diagnosis was the primary outcome. Descriptive analyses were used to compare baseline demographics and clinic characteristics. Multivariable logistic regression was used to evaluate race and ethnicity association with pretreatment clinical variables. Multivariable Cox regression was used to estimate the risk of metastasis.

RESULTS

Data from 7 889 984 veterans from the incidence cohort were used to estimate incidence, whereas data from 92 269 veterans with localized PCa were used to assess treatment response. Among 92 269 veterans, African American men (n = 28 802 [31%]) were younger (median [IQR], 63 [58-68] vs 65 [62-71] years) and had higher prostate-specific antigen levels (>20 ng/mL) at the time of diagnosis compared with White men (n = 63 467; [69%]). Consistent with US population-level data, African American veterans displayed a nearly 2-fold greater incidence of localized and de novo metastatic PCa compared with White men across VA centers nationwide. Among veterans screened for PCa, African American men had a 29% increased risk of PCa detection on a diagnostic prostate biopsy compared with White (hazard ratio, 1.29; 95% CI, 1.27-1.31; P < .001). African American men who received definitive primary treatment of PCa experienced a lower risk of metastasis (hazard ratio, 0.89; 95% CI, 0.83-0.95; P < .001). However, African American men who received nondefinitive treatment classified as “other” were more likely to develop metastasis (adjusted hazard ratio, 1.29; 95% CI, 1.17-1.42; P < .001). Using the actual rate of metastasis from veterans who received definitive primary treatment, a persistent residual metastatic burden for African American men was observed across all National Comprehensive Cancer Network risk groups (low risk, 4 vs 2 per 100 000; intermediate risk, 13 vs 6 per 100 000; high risk, 19 vs 9 per 100 000).

CONCLUSIONS AND RELEVANCE

This cohort analysis found significant disparities in the incidence of localized and metastatic PCa between African American veterans and White veterans. This increased incidence is a major factor associated with the residual disparity in PCa metastasis observed in African American veterans compared with White veterans despite their nearly equal response to treatment.

Association Between Operative Approach and Venous Thromboembolism Rate Following Hepatectomy: a Propensity-Matched Analysis

BACKGROUND

The use of minimally invasive approaches to hepatectomy has increased in recent years, but the risk of postoperative venous thromboembolism (VTE) is undefined. We aimed to compare VTE rates after open hepatectomy and minimally invasive hepatectomy using an administrative dataset.

STUDY DESIGN

Patients with primary or metastatic liver tumors were identified in the National Surgical Quality Improvement Program-targeted hepatectomy database (2016-2018). VTE was compared between patients who underwent open or minimally invasive hepatectomy after a propensity score matching of 1:1 for demographics, comorbidities, and operative factors.

RESULTS

A total of 6935 patients underwent open hepatectomy and 2237 underwent minimally invasive hepatectomy. After matching, there were 1968 patients per group without differences in demographics, comorbidities, or operative variables. Prior to matching, the VTE rate was higher among patients who underwent open hepatectomy (2.8% vs. 1.1%, p < 0.001), and open hepatectomy was independently associated with VTE (OR = 1.90, p = 0.006). The VTE rate remained higher among open hepatectomy compared to minimally invasive hepatectomy after matching (2.4% vs. 1.1%, p = 0.003). Open hepatectomy was associated with a higher VTE rate in patients undergoing minor (1.9 vs. 1.0%, p = 0.028) and major hepatectomy (5.0 vs. 1.9%, p = 0.045).

CONCLUSION

Patients who undergo an open hepatectomy for malignancy have a higher incidence of postoperative VTE compared to minimally invasive hepatectomy for both minor and major hepatectomy.

Data Matching to Support Analysis of Cancer Epidemiology Among Veterans Compared With Non-Veteran Populations-An Exemplar in Brain Tumors

PURPOSE

State and national cancer registries do not systematically include Veteran data, which hinders analysis of the diagnosis patterns, treatment trajectories, and clinical outcomes of Veterans compared with non-Veteran populations. This study used data matching approaches to compare cases included in the Oncology Domain of the Veterans Affairs (VA) Corporate Data Warehouse and the Ohio Cancer Incidence Surveillance System, using brain tumors as an exemplar.

METHODS

We used direct data matching, on the basis of protected health information (PHI) common to both databases, to compare primary brain tumors from Veterans and non-Veterans diagnosed from 2000 to 2016. Working with this matched data set, we used six data elements that did not contain PHI, to assess the feasibility of using deterministic data matching to compare Veterans and non-Veterans.

RESULTS

Between 2000 and 2016, 223 Veterans from Ohio had a primary brain tumor; of those, 55 (25%) were not included in Ohio Cancer Incidence Surveillance System. Direct data matching showed that Veterans experienced a greater proportion of glioblastomas (41%) compared with non-Veterans (21%). Sex did not account for this difference. Deterministic data matching within the matched data set found that 75% (126 of 168) of Veterans had exact matches for at least five of six non-PHI variables common to both databases.

CONCLUSION

This study indicated that direct and deterministic data matching approaches to compare brain tumors in Veterans and in non-Veterans is feasible. This approach has the potential to promote comparisons of the distribution of tumors, the impact of chemical and environmental exposures, treatment trajectories, and clinical outcomes among Veteran and non-Veteran populations with brain tumors as well as other cancers and rare diseases.

A polymorphism in the promoter of FRAS1 is a candidate SNP associated with metastatic prostate cancer

BACKGROUND

Inflammation and one of its mediators, NF-kappa B (NFκB), have been implicated in prostate cancer carcinogenesis. We assessed whether germline polymorphisms associated with NFκB are associated with the risk of developing lethal disease (metastases or death from prostate cancer).

METHODS

Using a Bayesian approach leveraging NFκB biology with integration of publicly available datasets we used a previously defined genome-wide functional association network specific to NFκB and lethal prostate cancer. A dense-module-searching method identified modules enriched with significant genes from a genome-wide association study (GWAS) study in a discovery data set, Physicians' Health Study and Health Professionals Follow-up Study (PHS/HPFS). The top 48 candidate single nucleotide polymorphisms (SNPs) from the dense-module-searching method were then assessed in an independent prostate cancer cohort and the one SNP reproducibly associated with lethality was tested in a third cohort. Logistic regression models evaluated the association between each SNP and lethal prostate cancer. The candidate SNP was assessed for association with lethal prostate cancer in 6 of 28 studies in the prostate cancer association group to investigate cancer associated alterations in the genome (PRACTICAL) Consortium where there was some medical record review for death ascertainment which also had SNP data from the ONCOARRAY platform. All men self-identified as Caucasian.

RESULTS

The rs1910301 SNP which was reproducibly associated with lethal disease was nominally associated with lethal disease (odds ratio [OR] = 1.40; p = .02) in the discovery cohort and the minor allele was also associated with lethal disease in two independent cohorts (OR = 1.35; p = .04 and OR = 1.35; p = .07). Fixed effects meta-analysis of all three cohorts found an association: OR = 1.37 (95% confidence interval [CI]: 1.15-1.62, p = .0003). This SNP is in the promoter region of FRAS1, a gene involved in epidermal-basement membrane adhesion and is present at a higher frequency in men with African ancestry. No association was found in the subset of studies from the PRACTICAL consortium studies which had a total of 106 deaths out total of 3263 patients and a median follow-up of 4.4 years.

CONCLUSIONS

Through its connection with the NFκB pathway, a candidate SNP with a higher frequency in men of African ancestry without cancer was found to be associated with lethal prostate cancer across three well-annotated independent cohorts of Caucasian men.

Abstract 863: Circadian gene expression in metastatic sites and association with survival in metastatic castration-resistant prostate cancer

Introduction: In experimental and epidemiological studies, alterations in several core circadian genes at the germline and tumor level have been associated with prostate cancer. The aim of this study was to investigate mRNA expression of circadian related genes in men with metastatic castration-resistant prostate cancer (mCRPC), and the association with survival.

Methods: We assessed whole exome and RNA sequencing data from 317 mCRPC patients from the Stand Up to Cancer-Prostate Cancer Foundation (SU2C-PCF) database. Data were obtained from six sites: metastasis to bone (n=107; n=65 deaths), lymph node (n=129; n=88 deaths), liver (n=42; n=35 deaths), lung (n=6; n=3 deaths), and other soft tissue (n=26; n=20 deaths), as well as primary prostate (n=7; n=5 deaths) over a median follow-up of 71.8 months. We evaluated expression of twelve core circadian genes (ARNTL, CLOCK, CRY1, CRY2, CSNK1E, NR1D1, NPAS2, PER1, PER2, PER3, RORA, TIMELESS) as transcripts per million (TPM). We used the correlation of correlations method to estimate inter-gene correlations between tissue. Unpaired Wilcoxon rank sum tests compared circadian expression differences with tumor mutations in AR and p53, two of the most common genomic alterations in mCRPC. We conducted multivariable Cox regression, overall and stratified by tissue type, to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for expression (modeled continuously) and overall survival, adjusted for age and PSA at diagnosis, Gleason, treatment, and histology.

Results: Many genes showed low or negative correlation across tissues, with the greatest discordance in CSNK1E (μICC=0.10), and greatest concordance in TIMELESS (μICC=0.55). Lower expression of ARNTL was found in patients with alterations to both p53 and AR. Similarly, higher expression of PER2 and RORA was found in AR-/p53+, compared to those AR+ and AR-/p53-. Higher expression of TIMELESS was associated with risk of death overall and across all tissue sites (HRoverall: 1.02, 95% CI: 1.01-1.03). In liver, higher expression of CLOCK (HR: 0.22, 95% CI: 0.07 - 0.71) and CSNK1E (HR: 0.87, 95% CI: 0.76 - 1.00), and lower expression of CRY1 (HR: 1.62, 95% CI: 1.16 - 2.26) was associated with a lower risk of death. Higher expression of CRY2 (HR: 1.25, 95% CI: 1.02 - 1.53) in liver, but lower expression in bone (HR: 0.95, 95% CI: 0.90 - 1.00) was associated with an increased risk of death. We found no association between ARNTL, NR1D1, NPAS2, PER3, or RORA and survival in any metastatic site.

Conclusion: Our results show that circadian gene expression is altered in tissue from mCRPC patients, with substantial heterogeneity in circadian related expression patterns between metastatic tissue sites. These results support prior research on the role of circadian gene expression, particularly CRY1 and CLOCK, and outcomes in localized prostate cancer.

Citation Format: Benjamin D. Booker, Konrad H. Stopsack, Travis A. Gerke, Kathryn Penny, Philip W. Kantoff, Lorelei A. Mucci, Sarah C. Markt, PCF/SU2C International Prostate Cancer Dream Team. Circadian gene expression in metastatic sites and association with survival in metastatic castration-resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 863.

Recommended Definitions of Aggressive Prostate Cancer for Etiologic Epidemiologic Research

BACKGROUND

In the era of widespread prostate-specific antigen testing, it is important to focus etiologic research on the outcome of aggressive prostate cancer, but studies have defined this outcome differently. We aimed to develop an evidence-based consensus definition of aggressive prostate cancer using clinical features at diagnosis for etiologic epidemiologic research.

METHODS

Among prostate cancer cases diagnosed in 2007 in the National Cancer Institute's Surveillance, Epidemiology, and End Results-18 database with follow-up through 2017, we compared the performance of categorizations of aggressive prostate cancer in discriminating fatal prostate cancer within 10 years of diagnosis, placing the most emphasis on sensitivity and positive predictive value (PPV).

RESULTS

In our case population (n = 55 900), 3073 men died of prostate cancer within 10 years. Among 12 definitions that included TNM staging and Gleason score, sensitivities ranged from 0.64 to 0.89 and PPVs ranged from 0.09 to 0.23. We propose defining aggressive prostate cancer as diagnosis of category T4 or N1 or M1 or Gleason score of 8 or greater prostate cancer, because this definition had one of the higher PPVs (0.23, 95% confidence interval = 0.22 to 0.24) and reasonable sensitivity (0.66, 95% confidence interval = 0.64 to 0.67) for prostate cancer death within 10 years. Results were similar across sensitivity analyses.

CONCLUSIONS

We recommend that etiologic epidemiologic studies of prostate cancer report results for this definition of aggressive prostate cancer. We also recommend that studies separately report results for advanced category (T4 or N1 or M1), high-grade (Gleason score ≥8), and fatal prostate cancer. Use of this comprehensive set of endpoints will facilitate comparison of results from different studies and help elucidate prostate cancer etiology.

Exploratory assessment of pineal gland volume, composition, and urinary 6-sulfatoxymelatonin levels on prostate cancer risk

INTRODUCTION

Melatonin levels are partially driven by the parenchyma volume of the pineal gland. Low urinary levels of 6-sulfatoxymelatonin have been associated with increased risk of advanced prostate cancer, but the relationship between pineal gland volume and composition and prostate cancer risk has not been examined.

MATERIALS AND METHODS

We utilized data from 864 men from the AGES-Reykjavik Study with complete pineal gland volumes and urinary 6-sulfatoxymelatonin measurements. Pineal parenchyma, calcification, and cyst volumes were calculated from brain magnetic resonance imaging. Levels of 6-sulfatoxymelatonin were assayed from prediagnostic urine samples. We calculated Pearson correlation coefficients between parenchyma volume and urinary 6-sulfatoxymelatonin levels. We used Cox proportional hazards regression to calculate multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs) comparing prostate cancer risk across parenchyma volume tertiles and across categories factoring in parenchyma volume, gland composition, and urinary 6-sulfatoxymelatonin level.

RESULTS

Parenchyma volume was moderately correlated with urinary 6-sulfatoxymelatonin level (r = .24; p < .01). There was no statistically significant association between parenchyma volume tertile and prostate cancer risk. Men with high parenchyma volume, pineal cysts and calcifications, and low urinary 6-sulfatoxymelatonin levels had almost twice the risk of total prostate cancer as men with low parenchyma volume, no pineal calcifications or cysts, and low urinary 6-sulfatoxymelatonin levels (HR: 1.98; 95% CI: 1.02, 3.84; p: .04).

CONCLUSIONS

Although parenchyma volume is not associated with prostate cancer risk, pineal gland composition and other circadian dynamics may influence risk for prostate cancer. Additional studies are needed to examine the interplay of pineal gland volume, composition, and melatonin levels on prostate cancer risk.

Choosing unwisely: Low-value care in older adults with a diagnosis of myelodysplastic syndrome

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Background: In tandem with the Choosing Wisely initiative, ASCO’s Cost of Care Task Force has proposed a list of low-value (LV) procedures and therapies that may be of limited benefit to patients. Myelodysplastic syndrome (MDS) is the most common myeloid malignancy in the US. A complete diagnostic evaluation (CDE) of MDS requires a bone marrow biopsy, fluorescence in situ hybridization and chromosomal analysis. As a potential LV procedure, we evaluated receipt of CDE in MDS patients with isolated or no cytopenias and no transfusion dependence. Methods: Using national 2011-2014 Medicare data, we identified fee-for-service Medicare patients 66 years of age or older with an MDS diagnosis, one or no cytopenias, and no blood transfusions in the 16 weeks before or after an MDS diagnosis (n = 16,779). We examined the following variables that may have provided a clinical context to (or not to) pursue CDE – demographics (age, race, sex); number of Elixhauser comorbid conditions ( < 5 vs >5); nursing home status, prior history of lymphoma, myeloma, MGUS and other cancers; chronic kidney disease (CKD); colonoscopy; and therapies received including erythropoiesis stimulating agents (ESAs), hypomethylating agents (HMAs) or lenalidomide. We conducted Classification and Regression Tree (CART) analysis, a machine learning approach to identify combinations of factors in patients with little clinical justification for CDE, and Cox proportional hazards regression analysis to compare survival outcomes between those with or without CDE. Results: Over half of our study population (51%) received CDE. Of those, 46.6% were 80 years of age or older, 4.8% were nursing home residents; and 33.6% had 5 or more chronic conditions. Results from CART analysis showed that among patients with an isolated cytopenia (e.g., isolated anemia), 46.0% of patients >80 years (n = 860), and 57.7% (n = 1,156) of those in the 66-79 age group underwent CDE in the absence of CKD, colonoscopy, HMA, or ESA. Among those with no cytopenia (n = 3890), 866 patients received CDE in the absence of HMA, ESA, or history of lymphoma or progression to leukemia. In adjusted analyses, no survival benefit was associated with receipt of CDE (p = 0.24). Conclusions: A substantial number of patients with an MDS diagnosis, isolated or no cytopenias, and no transfusion dependence received a CDE in the absence of other diagnoses, procedures, or therapies that may have explained the clinical decision to perform CDE. These procedures entail costs, pain and anxiety, but do not appear to yield useful information to guide clinical management, as evidenced by the comparable survival outcomes between patients who did and did not undergo CDE. To promote patient-centered care, careful patient selection that reduces unnecessary CDE in MDS patients should be a priority in clinical decision-making.

Variation in the use of genomic testing in patients with metastatic colorectal cancer

e15557

Background: Oncology has greatly benefited from the use of clinical genomics to aid diagnostic and treatment decisions. To inform targeted therapy, standard practice dictates molecular testing of metastatic colorectal cancer (mCRC) tumors through genomic testing (GT), including molecular biomarker, single gene, or next-generation sequencing (NGS). While persisting disparities in CRC screening, treatment, and outcomes have been well described, little is known about differences in GT for mCRC. Using all-payer electronic health record-derived de-identified data from a real-world database generated from routine clinical care across the U.S., we identified combinations of demographic and clinical characteristics, rather than individual factors, associated with GT. Methods: This study used the nationwide Flatiron Health electronic health record (EHR)-derived de-identified database. During the study period, the de-identified data originated from approximately 280 US cancer clinics (̃800 sites of care). Our study population included 26,524 patients with mCRC during the years 2013-2020. We evaluated documentation of receipt of GT (individual biomarker or NGS) measured within one year of diagnosis of metastatic disease, by demographic (age, sex, and race/ethnicity), payer type, de novo metastatic cancer (vs. progression to metastatic disease), tumor site (colon vs. rectum), Eastern Cooperative Oncology Group (ECOG) performance status, and year of diagnosis. We identified Elixhauser comorbid conditions from ICD codes, and grouped them by count (0-4, 5+). We conducted Classification and Regression Tree (CART) analysis, a machine learning approach to identify combinations of demographic and clinical characteristics associated with receipt of GT. Results: Nearly 83% had documented GT, 90% of whom did so within 6 months of diagnosis. The largest group of patients with GT at 90% consisted of individuals with colon cancer, 64 years of age or younger, 0-4 comorbidities, and an ECOG score of 0 or 1 (n = 2,004). Conversely, the lowest rates of GT ( < 60%) were observed among women 75 years of age or older, despite having 0-4 comorbidities (n = 1,314). In this group of patients, GT was higher among those with ECOG score of 1 than among those with high ECOG scores (66% and 54%, respectively). On the other hand, 71% of patients 75 years of age or older with 5+ comorbidities and high ECOG scores received GT. Conclusions: Considerable variations exist in GT across subgroups of the population. Additional analysis is warranted to characterize young and healthy patients who did not receive GT, and those who did get tested despite their older age and compromised health status. Future analyses will investigate whether documentation of receipt of GT is associated with treatment decisions and outcomes.

Immunotherapy Is Associated with a Survival Benefit in Patients Receiving Chemotherapy for Metastatic Pancreatic Cancer

Background: Immunotherapy (IT) has led to improved survival in several common cancers but success in pancreatic ductal adenocarcinoma (PDAC) has been limited. We analyzed if combination IT-chemotherapy (IT-CT) is associated with improved survival compared with chemotherapy alone (CT) in patients with metastatic PDAC. Methods: The National Cancer Database (2004-2016) was queried for patients who were diagnosed with metastatic PDAC. Patients were categorized by treatment group: CT only and IT-CT. Patients were excluded if they received radiation or a surgical procedure. The primary outcome was overall survival. Results: A total of 59,289 patients were identified, of whom 58,947 (99.4%) received CT and 342 (0.6%) received IT-CT. The IT-CT group was younger, had fewer comorbidities, and was more often treated at an academic center. The utilization of multiagent CT was similar between the groups. Median survival of patients treated with IT-CT was longer than CT alone (7.9 months vs. 6.3 months, p = 0.005). On multivariable analysis, receipt of IT-CT was associated with a survival advantage as compared with CT (hazard ratio = 0.86, 95% confidence intervals 0.76-0.97) when adjusting for demographics and type of CT regimen. Conclusion: In patients with metastatic PDAC, it appears that combination IT-CT may perhaps be associated with a survival advantage compared with CT alone.

Weight Loss as an Untapped Early Detection Marker in Pancreatic and Periampullary Cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has the worst survival of common cancers, partly because there are no reliable early detection tests. Unintentional weight loss (≥ 5% decrease from baseline) has been linked to PDAC, but the frequency and severity of weight loss using objective measures, and its relationship to prognosis, have not been well characterized.

METHODS

We identified 390 patients with PDAC (all stages) and two or more prediagnosis weights in the electronic medical record. Percentage weight loss in the 365 and 180 days preceding diagnosis was calculated. Results were compared with raw weights of age- and sex-matched non-cancer controls (n = 780). Odds ratios for PDAC were calculated using conditional logistic regression. Cox proportional hazards models were used for survival.

RESULTS

Within 1 year of diagnosis, more PDAC patients lost ≥ 5% weight relative to controls (74.9% vs. 11.2%; p < 0.001), with a median weight loss of 14.2 versus 2.9 lbs. The odds ratio for PDAC comparing weight loss within 1 year of 5 to < 10% was 10.30 (p < 0.001) and 77.82 for ≥ 10% (p < 0.001), compared with stable weight. Weight loss prior to diagnosis was also associated with early-stage PDAC. PDAC cases with ≥ 10% prediagnosis weight loss had worse survival compared with stable weights (hazard ratio [HR] 1.60; p = 0.01). Greater prediagnosis weight loss was associated with poor survival after pancreatectomy (5 to < 10% vs. < 5%, HR 2.40, p = 0.03; ≥ 10% vs. < 5%, HR 2.59, p = 0.03).

CONCLUSIONS

Diagnosis of PDAC is preceded by unintentional weight loss in the majority of patients, even at an early stage. Greater prediagnosis weight loss severity is also associated with poor postoperative survival.

Receipt of Next-generation Genomic Sequencing among Patients with Metastatic Colorectal Cancer (mCRC) in a Real-World Cohort

Purpose of the Study: Disparities in genomic precision medicine approaches, through molecular profiling or next- generation sequencing (NGS), by race/ethnicity, insurance, and poverty have been identified in lung cancer, but not mCRC. Our goal was to examine disparities in receipt of NGS in patients with mCRC. Methods: We used all-payer electronic health record (EHR)-derived de-identified data from the Flatiron Health database generated from routine clinical care across the United States. Our study population included 26,524 patients with mCRC during the years 2013–2020. In addition to date of NGS testing, the FH-EHR data include demographics (age, sex, and race/ethnicity), payer type, and Eastern Cooperative Oncology Group (ECOG) performance status. We conducted descriptive analyses and multivariable logistic regression analysis to identify correlates of receipt of NGS within 6 months of metastatic diagnosis. Results: Among the 26,524 people with mCRC, 45% (n = 11,946) were women, 48% (n = 12,732) had a Commercial Health Plan, and the majority were seen in a community practice (92%) vs academic hospitals. Over 70% of the patients were White, 12% Black or African-American (AA), and 14% Other. Thirty-three percent (n = 8,821) of patients had documentation in the EHR of having received NGS. After simultaneously adjusting for other factors in the model, older age (ORper year increase: 0.97, 95% CI: 0.96–0.98) and Black/AA race (OR: 0.74, 95% CI: 0.68–0.81), compared to White, was associated with lower odds of receiving NGS testing. Conversely, female sex, better ECOG performance status, later calendar year, being seen in an academic practice, and having a Commercial Health Plan were associated with greater odds of receiving NGS. Conclusions: Our findings indicate that NGS is not received uniformly by all patients with mCRC. Future analyses will incorporate receipt of individual molecular biomarker tests, as recommended by professional societies, as well as their results (e.g., KRAS, NRAS, BRAF, MMR/MSI), treatment information, and survival.

Racial differences in aneuploidy in high-grade muscle-invasive bladder cancer

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Background: Bladder cancer is marked by racial disparities in stage at presentation, treatment, and survival. It is unknown how somatic tumor genomes differ by race. Tumor aneuploidy, defined as aberrant counts of chromosome arms, is pervasive in tumors including bladder cancer. Its associations with race are incompletely understood. We sought here to characterize the relation of race with aneuploidy in high-grade muscle-invasive bladder cancer. Methods: To quantify how aneuploidy differs by race, we leveraged the cohort of patients with high-grade, muscle-invasive bladder cancer from The Cancer Genome Atlas. Chromosome arm gains and losses were identified based on Affymetrix SNP 6.0 arrays (Taylor 2018). We focused on aneuploidy burden defined as the count of chromosome arms altered by gains and losses per tumor, which was based on both p and q chromosome arms of all autosomes except for acrocentric autosomes (q arms only) and ranged from 0 to 34 altered chromosome arms. We used multivariable linear regression to obtain mean differences and 95% confidence intervals (CIs) in the number of altered chromosome arms between self-reported racial groups, adjusting for demographics (sex, age at diagnosis, smoking status) and tumor characteristics (grade, histology). We also evaluated associations between race and number of altered chromosome arms stratified by papillary/non-papillary histology and sex. Results: Of 362 participants, 315 self-identified as White (87%), 25 as Asian (7%), and 22 as Black (6%). 73% were men, 21% were current smokers, and 52% former smokers. Median age at diagnosis was 69 years (interquartile range [IQR]: 61 to 76). Asians and Blacks tended to be younger at diagnosis than Whites, with more never-smokers among Asians. More profiled tumors were of papillary histology among Asians (44%), and fewer among Blacks (18%), than among Whites (30%). Aneuploidy burden was high overall (median, 14 altered chromosome arms; IQR: 8 to 19); only 17% of tumors had five or fewer altered chromosome arms. Compared to Whites, aneuploidy burden overall was similar in tumors from Asians (adjusted mean difference, –2.3 fewer altered chromosome arms; 95% CI: –5.4 to 0.9) and Blacks (–1.7; 95% CI: –5.1 to 1.7). Asian race appeared more strongly associated with lower aneuploidy burden in non-papillary tumors (–3.9 altered chromosome arms; 95% CI: –7.7 to –0.1) than in papillary tumors (–0.3; 95% CI: –5.6 to 5.0), and in men (–3.5; 95% CI: –7.0 to 0.1) than in women (–0.8; 95% CI: –6.8 to 5.2). Conclusions: These findings suggest potential differences in aneuploidy burden between Asians and Whites among high-grade muscle-invasive bladder cancers. They also highlight a need for validation in cohorts that are more racially diverse and have a well-defined source population (study base) with detailed data on cancer risk factors and histopathology.

Facility volume-survival relationship in patients with early-stage pancreatic adenocarcinoma treated with neoadjuvant chemotherapy followed by pancreatoduodenectomy

BACKGROUND

There is evidence that neoadjuvant therapy is associated with improved survival compared with upfront pancreatectomy for pancreatic adenocarcinoma. Treatment at high-volume pancreatic surgery centers is associated with improved short-term postoperative outcomes compared with low-volume centers. We compared overall survival of patients with early-stage pancreatic adenocarcinoma who received neoadjuvant therapy before resection stratified by facility volume.

METHODS

Patients with clinical T0 to T2 pancreatic adenocarcinoma who received neoadjuvant therapy before pancreatoduodenectomy were identified in the National Cancer Database (2010-2016). High-volume pancreatic surgery centers performed ≥36 pancreatectomies/year. Patients were matched 1:1 by propensity score. Pathologic outcomes, postoperative outcomes, and overall survival were compared.

RESULTS

Before matching, 1,449 patients were treated at low-volume centers and 250 at high-volume pancreatic surgery centers. After matching, there were 177 patients per group. High-volume pancreatic surgery centers were more commonly academic/research facilities (99.4% vs 54.0%; P < .001), and patients traveled greater distances (65 vs 13 miles; P < .001). Time from diagnosis to neoadjuvant therapy and surgery was similar. Treatment at high-volume pancreatic surgery centers was associated with shorter duration of stay (7 vs 8 days; P = .003) and lower 90-day mortality rate after pancreatoduodenectomy (0.0% vs 5.0%; P = .01). Patients treated at high-volume pancreatic surgery centers had improved overall survival (36.3 vs 29.4 months; P = .03; hazard ratio 0.73). On subset analysis of academic/research facilities, high-volume pancreatic surgery centers remained associated with shorter duration of stay, lower 90-day mortality, and greater overall survival.

CONCLUSION

The majority of patients treated with neoadjuvant therapy for early-stage pancreatic adenocarcinoma received care at low-volume centers. Treatment at high-volume pancreatic surgery centers was associated with improved overall survival and short-term postoperative outcomes.

Sleep quality and prostate cancer aggressiveness: Results from the REDUCE trial

BACKGROUND

Disrupted sleep has been associated with increased risk of certain cancers. Little data exist in prostate cancer. We tested the association between sleep quality and prostate cancer diagnosis overall and by tumor grade in the Reduction by Dutasteride of Prostate Cancer Events chemoprevention trial. We hypothesized that worse sleep quality would be associated with increased tumor aggressiveness.

METHODS

At baseline, 5614 men completed a validated six-item questionnaire on sleep quality. We generated a composite score categorized into tertiles to measure overall sleep quality and assessed each sleep quality question individually. Logistic regression was used to test associations between baseline sleep quality and overall, low-grade and high-grade prostate cancer diagnosis at 2-year study-mandated biopsy. Models were stratified by nocturia.

RESULTS

Overall sleep quality was unrelated to overall or low-grade prostate cancer. Worse overall sleep quality was associated with elevated odds of high-grade prostate cancer (odds ratio [OR]_T3vsT1 1.15; 95% confidence interval [CI]: 0.83-1.60 and OR_T2vsT1 1.39; 95% CI: 1.01-1.92). Men reporting trouble falling asleep at night sometimes vs never had elevated odds of high-grade prostate cancer (OR: 1.51; 95% CI: 1.08-2.09) while trouble staying awake during the day was associated with decreased odds of low-grade prostate cancer (OR: 0.65; 95% CI: 0.49-0.86). Results were similar within strata of nocturia severity.

CONCLUSIONS

Overall, associations between sleep quality and prostate cancer were inconsistent. However, there was some evidence for a positive association between insomnia and high-grade prostate cancer, and an inverse relationship between daytime sleepiness and low-grade prostate cancer; findings that should be validated by future studies.

Reassessing the role of surgery in the elderly or chronically sick with proximal extrahepatic cholangiocarcinoma

BACKGROUND

Most data on postoperative outcomes among patients with proximal extrahepatic cholangiocarcinoma are reported by single institutions. The purpose of this study was to analyze postoperative outcomes stratified by age and comorbidities.

METHODS

Patients with proximal extrahepatic cholangiocarcinoma who underwent a resection were identified in the National Cancer Database. Pathologic, postoperative, and survival outcomes were compared based on age and Charlson-Deyo comorbidity index.

RESULTS

Among the 1,579 patients, the average age was 66 years, and 9.4% of patients were older than 80 years. Most patients had a Charlson-Deyo score of 0 (72.4%), with the minority having scores of 1 (20.5%) or ≥2 (7.1%). Patients ≥80 years had a higher 90-day mortality rate compared with patients 65 to 79 and <65 years (21.3% vs 12.0% vs 7.4%, P < .001). Patients with a Charlson-Deyo score ≥2 had longer duration of stay, greater likelihood of requiring an unplanned readmission, and a higher 90-day mortality rate compared with patients with a lower comorbidity index. Median survival of patients <65, 65 to 79, and ≥80 years was 31, 24, and 17 months, respectively. A similar trend was seen with increasing Charlson-Deyo score (0: 27 months, 1: 25 months, ≥2: 20 months). On multivariable analysis, age ≥80 years (hazard ratio = 1.52, P = .01) and Charlson-Deyo score ≥2 (hazard ratio = 1.45, P = .01) were associated with poor survival.

CONCLUSION

In patients with proximal extrahepatic cholangiocarcinoma, age ≥80 years and greater comorbidity index are associated with increased risk of 90-day mortality and poor overall survival. This suggests that resections in high-risk patient populations should be approached with caution.

Patient-centered Weight Tracking as an Early Cancer Detection Strategy

Early detection is a valued strategy to decrease cancer mortality rates; however, new strategies are needed. Unintentional weight loss (UWL) is experienced by patients across the cancer spectrum, but often goes unnoticed. Patient-centered weight tracking may be a useful early detection marker. Fifty patients were enrolled in a prospective patient-centered weight tracking trial. Patients received a scale and monetary compensation to participate. A reminder to measure and record weight was texted to participants for 26 consecutive weeks. Most patients were black (86.0%) and female (68.0%). The median age was 47 years (range: 22-84 years). Many participants had Medicaid (42.0%) and the median household income by home zip code was $31,046. After 26 weeks, 90% of patients had recorded at least one weight. Among all patients, 73.7% of all possible weights were recorded and the median response rate per patient was 92.3% (24 of 26 weights). There was no difference in the response rates during the first and second halves of the study (77.7% vs. 69.7%, P = 0.53). The range of weight change over the study period was 16.1% loss to 25.0% gain, with 56% of patients maintaining stable weight. Seven patients (14.0%) lost more than 5% weight and 11 patients (22.0%) gained over 5%. Of the seven patients with weight loss, two (4.0% of the cohort) were determined to have UWL. Patient-centered weight tracking is feasible and inexpensive, and has potential as an early detector of UWL. Further studies are needed to apply this strategy to detect underlying malignancies.

Abstract C046: Racial and ethnic differences in the association of body mass index (BMI) and melatonin levels among men in the Multiethnic Cohort Study

Purpose Obesity and circadian rhythm disruption are risk factors for various cancers, including advanced prostate cancer. Given the differences in obesity rates by racial groups, the emerging evidence suggesting racial differences in circadian function, and the well-known racial disparities in cancer incidence and mortality, we aimed to explore the association between obesity and melatonin levels within a diverse population and assess how this association differed by racial/ethnic group. Methods This study leveraged 2,786 male controls from a nested case-control study within the Multiethnic Cohort Study. Melatonin was measured by its primary metabolite, 6-sulfatoxymelatonin, in first-morning void and overnight urine samples collected between 2001 and 2006 prior to cancer diagnosis. We categorized men based on body mass index (BMI) as underweight:&lt;18.5 kg/m2; normal: 18.5 kg/m2 to &lt;25 kg/m2; overweight: 25 kg/m2 to &lt;30 kg/m2; and obese: 30 kg/m2. We used linear regression models to evaluate the association between obesity and melatonin levels, adjusted for urinary creatinine levels, age, race/ethnicity, occupation, years of schooling, month of urine collection, sleep duration, physical activity, smoking, and alcohol use. We further examined associations between obesity and melatonin within racial/ethnic groups. Results The prevalence of obesity differed by race/ethnicity, with 34.3% of Native Hawaiian (NH), 25.0% of African American (AA), 22.1% of Latino, 14.8% of White, and 10.6% of Japanese men categorized as obese (chisq p-value &lt; 0.001). Latino and White men had the highest levels of melatonin with a median of 25.1 ng melatonin/mg creatinine; the median levels in Japanese (23.4 ng/mg), AA (23.0 ng/mg), and NH men (22.3 ng/mg) were lower (Kruskal-Wallis p-value=0.03). These differences remained after adjusting for BMI, with AAs having the lowest and Latinos the highest melatonin levels. In multivariable models, men who were obese had melatonin levels that were 16.9% (95% CI: 9.8%, 23.5%) lower than normal weight (NW) men. When stratified by race/ethnicity, we found that obese white men had 16.5% (95% CI: 3.0%, 28.1%) lower levels than NW white men; obese NH men had 23.7% (95% CI: 2.9%, 40.0%) lower levels than NW NH men; and obese Japanese men had 18.4% (95% CI: 7.5%, 28.1%) lower levels than NW Japanese men. Although not statistically significant, obesity was associated with lower melatonin levels among AA (13.9% lower, 95% CI: 29.6% lower, 5.2 % higher) and Latino (8.6% lower, 95% CI: 28.5% lower, 17.0% higher) men. Conclusion To our knowledge, this is the first study looking at the association between obesity and melatonin levels in a diverse population of men. We found that obese men had lower melatonin levels and that melatonin levels and obesity rates differed by racial groups. These findings will be expanded on to investigate the interplay between melatonin, obesity and race/ethnicity on risk of prostate cancer and potentially point to an underlying reason for racial disparities in cancer.

Citation Format: Ilkania M Chowdhury-Paulino, Iona Cheng, Unnur A Valdimarsdottir, Loic Le Marchand, Christopher A Haiman, Lynne Wilkens, Lorelei A Mucci, Sarah C Markt. Racial and ethnic differences in the association of body mass index (BMI) and melatonin levels among men in the Multiethnic Cohort Study [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr C046.

Baldness and Risk of Prostate Cancer in the Health Professionals Follow-up Study

BACKGROUND

The association between male pattern baldness and prostate cancer has been inconsistent. We prospectively investigated the association between baldness at age 45 and prostate cancer risk in the Health Professionals Follow-up Study (HPFS), focusing on clinical and molecular markers.

METHODS

Baldness was self-reported on the 1992 questionnaire using the modified Norwood-Hamilton scale prior to diagnosis. We estimated HRs between baldness and prostate cancer risk among 36,760 men, with follow-up through 2014. We also investigated whether baldness was associated with prostate cancer defined by tumor protein expression of androgen receptor and the presence of the TMPRSS2:ERG fusion.

RESULTS

During 22 years, 5,157 prostate cancer cases were identified. Fifty-six percent of the men had either frontal or vertex baldness. No significant associations were found between baldness and prostate cancer risk. Among men younger than 60 years, there was a statistically significant association between frontal and severe vertex baldness and overall prostate cancer (HR: 1.74; 95% confidence interval: 1.23-2.48). Baldness was not significantly associated with expression of molecular subtypes defined by AR and TMPRSS2:ERG IHC of prostate tumors.

CONCLUSIONS

This study showed no association between baldness at age 45 and prostate cancer risk, overall or for clinical or molecular markers. The association between baldness and overall prostate cancer among younger men is intriguing, but caution is warranted when interpreting this finding.

IMPACT

The null findings from this large cohort study, together with previous literature's inconclusive findings across baldness patterns, suggest that baldness is not a consistent biomarker for prostate cancer risk or progression.

Statin Use Is Associated with Lower Risk of PTEN-Null and Lethal Prostate Cancer

PURPOSE

Statins are associated with lower risk of aggressive prostate cancer, but lethal prostate cancer is understudied and contributing mechanisms are unclear. We prospectively examined statins and lethal prostate cancer risk in the Health Professionals Follow-up Study (HPFS), tested associations with molecular subtypes, and integrated gene expression profiling to identify putative mechanisms.

EXPERIMENTAL DESIGN

Our study included 44,126 men cancer-free in 1990, followed for prostate cancer incidence through 2014, with statin use recorded on biennial questionnaires. We used multivariable Cox regression to examine associations between statins and prostate cancer risk overall, by measures of clinically significant disease, and by ERG and PTEN status. In an exploratory analysis, age-adjusted gene set enrichment analysis identified statin-associated pathways enriched in tumor and adjacent normal prostate tissue.

RESULTS

During 24 years of follow-up, 6,305 prostate cancers were diagnosed and 801 (13%) were lethal (metastatic at diagnosis or metastatic/fatal during follow-up). Relative to never/past use, current statin use was inversely associated with risk of lethal prostate cancer [HR, 0.76; 95% confidence interval (CI), 0.60-0.96] but not overall disease. We found a strong inverse association for risk of PTEN-null cancers (HR, 0.40; 95% CI, 0.19-0.87) but not PTEN-intact cancers (HR, 1.18; 95% CI, 0.95-1.48; P heterogeneity = 0.01). Associations did not differ by ERG. Inflammation and immune pathways were enriched in normal prostate tissue of statin ever (n = 10) versus never users (n = 103).

CONCLUSIONS

Molecular tumor classification identified PTEN and inflammation/immune activation as potential mechanisms linking statins with lower lethal prostate cancer risk. These findings support a potential causal association and could inform selection of relevant biomarkers for statin clinical trials.

Causes and patterns of mortality in patients with lethal germ cell tumor (GCT)

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Background: Most metastatic GCTs are cured with cisplatin-based chemotherapy. Clinical factors of adverse GCT-specific survival have been identified, however patterns of death are not well-defined and would inform clinical care and biological investigation. Methods: This multi-institutional study pooled data of male pts with death related to GCT from high-volume adult GCT academic centers (Dana-Farber Cancer Institute, Memorial Sloan Kettering Cancer Center, Indiana University) over 20 years (1997-2017). Pts were annotated for site, stage, IGCCC risk, histology, primary therapy and relapse variables (including relapse histology, metastatic (met) burden, salvage and palliative therapies), and detailed cause of GCT death. Cox regression assessed associations with survival. Results: The pooled cohort of 620 pts comprised 90% non-seminoma, 21% mediastinal primary and at diagnosis, 59% were stage III, 64% poor risk; 48% received high-dose chemotherapy plus transplantation. Median survival (OS) from first relapse after metastasis was 12.0 mos. Leading causes of death were chemorefractory GCT (83.1%), secondary somatic malignancy (SSM) arising from teratoma (9.4%), acute toxicity (4.5%), late toxicity (2.3%) and progressive untransformed pure teratoma (0.8%). Late relapse (relapse >2 years after 1st-line therapy) occurred in 11.3% at a median of 5.9 yrs. Of these pts, 1/3 were stage I at initial diagnosis and 75% were good or intermediate risk at met diagnosis, and were more likely to have SSM histology/death vs early relapse. Late relapsing disease (HR 0.48, p<0.0001) and presence of SSM (HR 0.74, p=0.017) were associated with longer OS from first relapse after metastasis. Brain metastasis at any time occurred in 29.8%, associated with poorer OS. Conclusions: Comprehensive characterization of GCT-related death reveals a predominant pattern of mortality marked by de novo metastatic, poor-risk disease with subsequent early relapse and death due to chemorefractory non-teratomatous GCT. By contrast, a subset of pts with late-relapsing disease are more likely to have SSM-teratoma and a protracted clinical course. Lethal late relapses frequently occurred beyond 5 years, emphasizing the importance of long-term follow-up.

Association of Inherited Pathogenic Variants in Checkpoint Kinase 2 (CHEK2) With Susceptibility to Testicular Germ Cell Tumors

Importance

Approximately 50% of the risk for the development of testicular germ cell tumors (TGCTs) is estimated to be heritable, but no mendelian TGCT predisposition genes have yet been identified. It is hypothesized that inherited pathogenic DNA repair gene (DRG) alterations may drive susceptibility to TGCTs.

Objective

To systematically evaluate the enrichment of germline pathogenic variants in the mendelian cancer predisposition DRGs in patients with TGCTs vs healthy controls.

Design, Setting, and Participants

A case-control enrichment analysis was performed from January 2016 to May 2018 to screen for 48 DRGs in 205 unselected men with TGCT and 27 173 ancestry-matched cancer-free individuals from the Exome Aggregation Consortium cohort in the discovery stage. Significant findings were selectively replicated in independent cohorts of 448 unselected men with TGCTs and 442 population-matched controls, as well as 231 high-risk men with TGCTs and 3090 ancestry-matched controls. Statistical analysis took place from January to May 2018.

Main Outcomes and Measures

Gene-level enrichment analysis of germline pathogenic variants in individuals with TGCTs relative to cancer-free controls.

Results

Among 205 unselected men with TGCTs (mean [SD] age, 33.04 [9.67] years), 22 pathogenic germline DRG variants, one-third of which were in CHEK2 (OMIM 604373), were identified in 20 men (9.8%; 95% CI, 6.1%-14.7%). Unselected men with TGCTs were approximately 4 times more likely to carry germline loss-of-function CHEK2 variants compared with cancer-free individuals from the Exome Aggregation Consortium cohort (odds ratio [OR], 3.87; 95% CI, 1.65-8.86; nominal P = .006; q = 0.018). Similar enrichment was also seen in an independent cohort of 448 unselected Croatian men with TGCTs (mean [SD] age, 31.98 [8.11] years) vs 442 unselected Croatian men without TGCTs (at least 50 years of age at time of sample collection) (OR, >1.4; P = .03) and 231 high-risk men with TGCTs (mean [SD] age, 31.54 [9.24] years) vs 3090 men (all older than 50 years) from the Penn Medicine Biobank (OR, 6.30; 95% CI, 2.34-17.31; P = .001). The low-penetrance CHEK2 variant (p.Ile157Thr) was found to be a Croatian founder TGCT risk variant (OR, 3.93; 95% CI, 1.53-9.95; P = .002). Individuals with the pathogenic CHEK2 loss-of-function variants developed TGCTs 6 years earlier than individuals with CHEK2 wild-type alleles (5.95 years; 95% CI, 1.48-10.42; P = .009).

Conclusions and Relevance

This multicenter case-control analysis of men with or without TGCTs provides evidence for CHEK2 as a novel moderate-penetrance TGCT susceptibility gene, with potential clinical utility. In addition to highlighting DNA-repair deficiency as a potential mechanism driving TGCT susceptibility, this analysis also provides new avenues to explore management strategies and biological investigations for high-risk individuals.

Weight loss as an untapped early detection marker in pancreatic cancer

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Background: Pancreatic cancer has the worst survival of common cancers and there are no reliable early detection tests. While prior reports link unintentional weight loss (>5% decrease from baseline) to pancreatic cancer, there has never been a study documenting the frequency of this presenting sign using raw patient weight data. Methods: Patients at our institution with a pancreatic neoplasm (n=288) were queried using ICD-9 code 157.9 and ICD-10 code C25.9. Retrospective review identified 95 patients with pancreatic ductal adenocarcinoma and two or more prediagnosis weights (>7 days apart). Date of diagnosis was defined by the date of positive biopsy or encounter with surgical or medical oncology. Standard statistical analysis was performed. Results: Among the 95 patients, there was a slight preponderance of female (65.3%) and Caucasian (54.7%) patients. The median age at diagnosis was 71 (range: 41-90) and the median BMI was 25.6 kg/m2 (range: 15.4-49.5). 9.5% presented with clinical stage I disease, 27.3% with stage II, 9.5% with stage III, and 53.7% with stage IV. Within 1 year of diagnosis (range: 9-365 days), median weight loss was 7.1% of body weight (range: 0.2-34.5%). In this period, 71.6% of patients lost greater than 5% body weight and 32.6% lost over 10% (Table). In the 6 months before diagnosis (range: 9-180 days), median weight loss was 6.4% (range: 0.2-24.2%). A subgroup analysis of early (I, II) and late stage (III, IV) patients showed that those with late stage at presentation lost significantly more prediagnosis weight compared to the early stage patients (median 8.2% vs 5.6%, p=0.02) in a median of 175 days. Prior to diagnosis of late stage patients, 80.0% lost over 5% body weight and 38.3% lost over 10%. Conclusions: Diagnosis of pancreatic cancer is preceded by weight loss in the majority of cases, even at an early stage. Monitoring unintentional weight loss in otherwise asymptomatic patients may be an inexpensive and practical way to detect pancreatic cancer. [Table: see text]

Abstract 1574: Circadian clock gene expression and lethal prostate cancer outcomes

Background: Converging evidence points to a potential role of disruption of the circadian rhythm in prostate cancer progression. There is limited human data in prostate tissue examining the biological consequences of alterations in genes involved in circadian rhythm on outcomes among prostate cancer patients.

Methods: To test the hypothesis that tissue expression of circadian-related genes was associated with prostate cancer outcomes, we leveraged data from the Physicians' Health Study (PHS) and the Health Professionals Follow-Up Study (HPFS) prostate tumor cohorts. Whole transcriptome expression profiling was performed on 404 prostate cancer cases, including 113 lethal cases (metastatic disease or prostate cancer death) and 291 indolent cases (&gt;8 years from diagnosis without evidence of metastasis). Using logistic regression models, we assessed whether mRNA expression levels in tumor (N=404) or paired normal prostate tissue (N=202) of eleven circadian-related genes (AANAT, CLOCK, CRY1, CRY2, CSNK1E, MTNR1B, NPAS2, OPN4, PER1, PER2, PER3) were associated with lethal prostate cancer, stage (T2 vs. T3+), Gleason grade at diagnosis (&lt;8 vs. ≥8), and biomarkers of angiogenesis and apoptosis. We calculated odds ratios and 95% confidence intervals (95% CIs) per standard deviation increase in gene expression.

Results: Pathway analyses showed a statistically significant association between the eleven circadian genes and lethal disease (global test p-value = 5.1e-05). On an individual gene level, men with higher tumor expression of Period Circadian Regulator 1 (PER1) gene had a reduced risk of lethal disease, independent of grade and stage (OR: 0.75, 95% CI: 0.59-0.97). High tumor expression of PER1 (OR: 0.72, 95% CI: 0.57-0.91) and Cryptochrome Circadian Regulator 2 (CRY2) (OR: 0.79, 95% CI: 0.63-1.00) were associated with lower Gleason grade tumors. High tumor expression of PER1 was associated with lower levels of cell proliferation and lower levels of angiogenesis markers; Neuronal PAS Domain Protein 2 (NPAS2) was associated with markers of apoptosis. For none of the genes was expression in normal prostate tissue associated with lethal prostate cancer (global test p-value = 0.06).

Discussion: We found higher expression of several of the circadian related genes were associated with less aggressive prostate cancer features. In line with these findings, PER1 has been suggested to be a tumor suppressor in previous studies. This supports the idea that maintenance of circadian clock function may protect tumor progression.

Citation Format: Sarah C. Markt, Ericka Ebot, Iona Cheng, Lynne Wilkens, Ayesha Shafi, Karen Knudsen, Kathryn Penney, Lorelei Mucci, Travis Gerke. Circadian clock gene expression and lethal prostate cancer outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1574.

Body fat distribution on computed tomography imaging and prostate cancer risk and mortality in the AGES-Reykjavik study

BACKGROUND

The World Cancer Research Fund classifies as "strong evidence" the link between obesity and the risk of advanced prostate cancer. In light of the different hormonal profiles associated with where adipose is stored, this study investigated the role of objectively measured body fat distribution and the risk of clinically relevant prostate cancer.

METHODS

This was a prospective study of 1832 men in the Age, Gene/Environment Susceptibility-Reykjavik study. From 2002 to 2006, participants underwent baseline computed tomography imaging of fat deposition, bioelectric impedance analysis, and measurement of body mass index (BMI) and waist circumference. Men were followed through linkage with nationwide cancer registries for the incidence of total (n = 172), high-grade (Gleason grade ≥8; n = 43), advanced (≥cT3b/N1/M1 at diagnosis or fatal prostate cancer over follow-up; n = 41), and fatal prostate cancer (n = 31) through 2015. Cox regression was used to evaluate the association between adiposity measures and prostate cancer outcomes.

RESULTS

Among all men, visceral fat (hazard ratio [HR], 1.31 per 1-standard deviation [SD] increase; 95% confidence interval [CI], 1.00-1.72) and thigh subcutaneous fat (HR, 1.37 per 1-SD increase; 95% CI, 1.00-1.88) were associated with risk of advanced and fatal disease, respectively. Among men who were leaner based on BMI, visceral fat was associated with both advanced and fatal disease. BMI and waist circumference were associated with a higher risk of advanced and fatal disease. No adiposity measures were associated with total or high-grade disease.

CONCLUSIONS

Specific fat depots as well as BMI and waist circumference were associated with the risk of aggressive prostate cancer, which may help to elucidate underlying mechanisms and target intervention strategies.