Abstract B32: Are ovarian cancer risk factors different for women with endometriosis?

Background: Endometriosis is a common gynecologic disorder that affects approximately 10% of women of reproductive age. It is also a well-established risk factor for ovarian cancer. Whether hormonal-related and other risk factors for ovarian cancer (e.g., parity, oral contraceptive use) are the same for women with and without endometriosis is currently unknown.

Methods: We pooled questionnaire information from 10 population-based case-control studies participating in the Ovarian Cancer Association Consortium (OCAC). Data from 8,172 women with invasive epithelial ovarian cancer and 12,464 controls were included in our analysis. Associations of body mass index (BMI), parity, oral contraceptive use, breastfeeding, menopausal hormone therapy use, first-degree family history of ovarian cancer, tubal ligation, and hysterectomy with risk of ovarian cancer were stratified by history of endometriosis and analyzed using logistic regression. All models were conditioned on age, race/ethnicity, education, and OCAC study site. We fit an endometriosis interaction term for each risk factor to evaluate statistical interactions.

Results: Among women with no history of endometriosis, those who had hysterectomies showed a 12% increased risk of ovarian cancer compared to those with intact uteri (OR=1.12, 95% CI 1.01-1.24); an increased risk was not observed among women with endometriosis (OR=0.74, 95% CI 0.53-1.05; p-interaction=0.009). Use of estrogen-progestin hormone therapy was associated with decreased risk ovarian cancer for women with histories of endometriosis (OR=0.69, 95% CI 0.47-1.02), but not for those without endometriosis (OR=0.96, 95% CI 0.87-1.07; p-interaction=0.02). We did not observe any significant statistical interactions for the other risk factors considered, and no interactions were significant after consideration of multiple comparisons.

Conclusions: The associations of hysterectomy and menopausal estrogen-progestin hormone therapy use with risk of ovarian cancer seemed to differ by endometriosis status, suggesting interactions that may need to be considered in ovarian cancer risk profiling strategies. Future investigations into the biology underlying these interactions would be relevant.

Citation Format: Aruna Muthukumar, Lilah Khoja, Penelope M. Webb, Harvey Risch, Jennifer Doherty, Holly Harris, Marc Goodman, Roberta Ness, Francesmary Modugno, Susanne K. Kjaer, Allan Jensen, Joellen Schildkraut, Andrew Berchuck, Kathryn L. Terry, Daniel Cramer, Linda J. Titus, Hoda Anton-Culver, Argyrios Ziogas, Anna H. Wu, Malcolm C. Pike, Celeste L. Pearce, Alice W. Lee. Are ovarian cancer risk factors different for women with endometriosis? [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr B32.

Germline HOXB13 mutations p.G84E and p.R217C do not confer an increased breast cancer risk

In breast cancer, high levels of homeobox protein Hox-B13 (HOXB13) have been associated with disease progression of ER-positive breast cancer patients and resistance to tamoxifen treatment. Since HOXB13 p.G84E is a prostate cancer risk allele, we evaluated the association between HOXB13 germline mutations and breast cancer risk in a previous study consisting of 3,270 familial non-BRCA1/2 breast cancer cases and 2,327 controls from the Netherlands. Although both recurrent HOXB13 mutations p.G84E and p.R217C were not associated with breast cancer risk, the risk estimation for p.R217C was not very precise. To provide more conclusive evidence regarding the role of HOXB13 in breast cancer susceptibility, we here evaluated the association between HOXB13 mutations and increased breast cancer risk within 81 studies of the international Breast Cancer Association Consortium containing 68,521 invasive breast cancer patients and 54,865 controls. Both HOXB13 p.G84E and p.R217C did not associate with the development of breast cancer in European women, neither in the overall analysis (OR = 1.035, 95% CI = 0.859-1.246, P = 0.718 and OR = 0.798, 95% CI = 0.482-1.322, P = 0.381 respectively), nor in specific high-risk subgroups or breast cancer subtypes. Thus, although involved in breast cancer progression, HOXB13 is not a material breast cancer susceptibility gene.

Disparities by race, socioeconomic status, and insurance type in the receipt of NCCN guideline concordant care for select cancer types in California

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Background: There are a limited number of studies that have evaluated the association between National Comprehensive Cancer Network (NCCN) guideline adherence and survival across different cancers. We aim to assess the relationship between race/ethnicity, socioeconomic status (SES), insurance type and the receipt of NCCN guideline concordant cancer care and survival. Methods: This is a retrospective population-based cohort study of patients with 7 types of invasive cancer using the California Cancer Registry. Adherence with NCCN guidelines was defined by appropriate surgical, radiation, and chemo- or hormonal therapies. Multivariate logistic regression was used to evaluate the relationship between the patient, insurance type, tumor, and guideline adherence. Disease-specific survival analysis was performed using multivariate proportional hazards model. Results: A total of 543,198 patients were identified with invasive cancer between 2004-2017 (cases by disease type: breast 189,311, prostate 156,502, colon 80,102, liver 25,857, gastric 22,066, ovary 22,551, and cervix 16,691). The proportion of patients receiving NCCN guideline-concordant care varied by disease type. Non-concordant guideline treatment was associated with increased disease-specific mortality across all cancer types: breast (HR 1.28, 95%CI 1.23-1.33), prostate (HR 1.31, 95%CI 1.22-1.41), colon (HR 1.73, 95%CI 1.67-1.78), liver (HR 2.52, 95%CI 2.42-2.63), gastric (HR 2.38, 2.28-2.49), ovary (HR 1.32, 95%CI 1.26-1.38), and cervical cancer (HR 1.17, 95%CI 1.08-1.26). In multivariate models, compared to White, black patients were less likely to receive guideline concordant care for breast (OR 0.88, 95%CI 0.84-0.92), prostate (OR 0.90, 95%CI 0.86-0.93), colon (OR 0.85, 95%CI 0.79-0.92), and ovarian cancer (OR 0.71, 95%CI 0.62-0.82). Compared to Managed care insurance patients, Medicaid payer status was also associated with lower guideline concordant care for breast (OR 0.81, 95%CI 0.78-0.84), prostate (OR 0.91, 95%CI 0.86-0.97), colon (OR 0.70, 95%CI 0.65-0.75), gastric (OR 0.69, 95%CI 0.63-0.75), and liver cancer (OR 0.66, 95%CI 0.61-0.72). Conclusions: Less than half of cancer patients received NCCN guideline concordant care. There was an incremental relationship observed between SES and the likelihood of receiving guideline concordant care. Patients receiving non-guideline concordant care had worse disease-specific survival.

Relationship of the breast ductal carcinoma in situ (DCIS) immune microenvironment with clinicopathological features: An institutional experience

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Background: DCIS is usually treated with resection followed by 5 years of adjuvant endocrine therapy for hormone receptor (HR) + DCIS. Endocrine therapy is not used in HR- DCIS. Although DCIS is considered a precursor lesion to invasive breast cancer, the different molecular subtypes confer variable clinical outcomes. The host immune response plays a key role in breast cancer progression and response to therapy. However, relative to invasive breast cancer, the immune milieu of DCIS is less understood. This retrospective study compares the clinical outcomes and tumor microenvironment of HR+ and HR- DCIS in order to identify clinical and immunological features in HR- DCIS that may predict an increased risk of recurrence or progression to invasive breast cancer. Methods: A single institution retrospective chart review was performed to identify patients diagnosed with DCIS between 2012 and 2017. A clinico-pathologic data set, as well as the PD-L1 expression of the DCIS and TILs were collected and correlated with various outcomes. Results: Our cohort consisted of 20 cases of HR- DCIS and 50 cases of HR+ DCIS. Overall, 56% were Caucasian, 20% Asian, 18% Hispanic, and 6% African American. Of the HR- patients, 70% were Caucasian, 15% Hispanic, and 15% Asian. Of the 17 HR- patients with available HER2 data, 76% had HER2+, and 24% triple negative (TN) DCIS. 18% of the HR+ patients and 38% of the HR- patients were PD-L1+. 25% of the HR-/HER2+ patients, and 75% of the TN patients were PD-L1+. 6% of the HR+ patients developed recurrent disease, 2 with DCIS and 1 with invasive ductal carcinoma. 20% of the HR- patients had recurrent disease, all of whom were HER2+. Of the HR- patients that recurred, 2 recurred with metastatic disease, 1 with ipsilateral invasive ductal carcinoma, and 1 with DCIS. All 7 patients that recurred had original DCIS pathology showing a high nuclear grade. Our future results at the time of the meeting will expand on this cohort. Conclusions: This retrospective analysis showed that HR- DCIS conferred higher rates of local and distant recurrence. Therefore, there is a need for treatments to reduce the recurrence rates of HR- DCIS. There are ongoing clinical trials for the high risk, HR-/HER2+ DCIS subtype. TN DCIS is also an aggressive phenotype. Given the high rate of PD-L1 positivity we detected in TN DCIS, immune-based therapy may be useful in the adjuvant setting to reduce the risk of recurrence in this cohort of patients.

Disparities in the receipt of National Comprehensive Cancer Network (NCCN) guideline adherent care in triple-negative breast cancer (TNBC) by race/ethnicity, socioeconomic status, and insurance type

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Background: Breast cancer is the most commonly diagnosed cancer in women in the United States and the second leading cause of cancer mortality in women.TNBC is more likely to present at an earlier age with more advanced and aggressive disease. The overarching goal of treatment recommendations listed in the National Comprehensive Cancer Network (NCCN) guidelines are to improve patient outcomes. Here we examine factors which may contribute to NCCN guideline adherence. Methods: This was a retrospective cohort study of women with triple negative breast cancer using data from the California Cancer Registry (CCR) between 2004-2016 (with follow-up through 11/2018). Indicators for concordance with NCCN guidelines for TNBC was used as the dependent variable in the analysis. A multivariable logistic regression was used to determine the effects of independent variables on adherence to NCCN guidelines. Odds ratios and 95% Confidence Intervals (CI) were calculated. Non-Hispanic Whites, having medical insurance and highest socioeconomic status (SES) were set as references values in the regression models. Disease specific survival was calculated using the Cox regression analysis. Results: A total of 16,858 women were included in this study, 32.5% (n = 5,472) received NCCN adherent care (p < 0.0001). Non-Hispanic Blacks (NHB) and Hispanic patients were less likely to receive guideline adherent care (respectively, OR 0.87, 95%CI 0.79-0.95 and OR 0.87, 95%CI 0.79-0.95). Patients of lowest and lower-middle socioeconomic status (SES) were less likely to receive NCCN guideline adherent care (respectively, OR 0.77, 95%CI 0.68-0.87 and OR 0.88, 95%CI 0.79-0.98). Overall, non-adherent care was associated with an increased disease-specific mortality (HR 1.21, 95%CI 1.11-1.31, p < 0.0001). Hazard ratios were calculated after adjusting for adherent care and NHB patients had an increased disease-specific mortality (HR 1.28, 95%CI 1.16-1.42, p < 0.0001) in addition to patients with Medicare or Medicaid payer status (respectively, HR 1.20, 95%CI 1.08-1.34, p < 0.001 and HR 1.29, 95%CI 1.15-1.43, p < 0.0001). Conclusions: A significant portion of TNBC patients in California continue to receive non-guideline adherent care. Non-Hispanic black patients and lower SES quintile groups were less likely to receive guideline adherent care. Patients with non-adherent care had worse disease specific survival compared to recipients of NCCN-adherent care.

Population-based analysis of guideline adherence for patients with rectal cancer in California

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Background: The goal of oncology-specific evidence-based treatment guidelines is to improve cancer care. We sought to analyze adherence to National Comprehensive Cancer Network (NCCN) treatment guidelines for rectal cancer in the state of California and the associated impacts on survival. Methods: Patients aged 18 to 79 years diagnosed with rectal adenocarcinoma between January 1, 2004 and December 31, 2017 with follow-up through November 30, 2018 were identified in the California Cancer Registry. Patient characteristics such as age, race, insurance status, socioeconomic status (SES), marital status, and tumor stage were identified. In addition, based on available data our investigators determined whether patients received NCCN guideline-adherent care. Odds ratios (OR) and 95% confidence intervals (CI) were used for logistic regression to analyze patients receiving NCCN adherent care. Disease specific-survival analysis was calculated using Cox regression model. Results: A total of 30,118 patients identified with diagnosis of rectal cancer in California, 16,442 (54.6%) of whom did not receive guideline-adherent care. Disease specific-survival was worse for those who did not receive NCCN adherent care with hazard ratio (HR) 1.52 (95% CI 1.41 - 1.63, p < 0.0001). Compared to Caucasians as a referent group, Asians (in aggregate) were more likely to receive guideline adherent care and had better disease specific survival with adjusted HR 0.88 (95% CI 0.80 -0.97, p = 0.008). Also compared to Caucasians, Hispanics were more likely to receive guideline adherent care and had better disease specific survival HR 0.90 (95% CI 0.83 – 0.98, p < 0.015). As compared to managed care insured patients, uninsured patients were least likely to receive care and were observed to have worse disease specific survival adjusted HR 1.34 (95% CI 1.18 – 1.54, p < 0.0001). Patients with Medicaid were also significantly associated with lower survival HR 1.39 (95% CI 1.26 – 1.53, p < 0.0001) – and the CIs indicate Medicaid and uninsured were not statistically different from each other. Comparing to patients with highest SES as a referent group, patients with lowest SES were least likely to receive guideline adherent care and also were observed to have worse disease-specific survival with HR 1.22 (95% CI 1.09 – 1.36, p < 0.0004). Conclusions: In this population-based analysis of rectal cancer patients in California, guideline-adherent care was associated with improved survival.

Association between genetically predicted polycystic ovary syndrome and ovarian cancer: a Mendelian randomization study

BACKGROUND

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder with an estimated prevalence of 4-21% in reproductive aged women. Recently, the Ovarian Cancer Association Consortium (OCAC) reported a decreased risk of invasive ovarian cancer among women with self-reported PCOS. However, given the limitations of self-reported PCOS, the validity of these observed associations remains uncertain. Therefore, we sought to use Mendelian randomization with genetic markers as a proxy for PCOS, to examine the association between PCOS and ovarian cancer.

METHODS

Utilizing 14 single nucleotide polymorphisms (SNPs) previously associated with PCOS we assessed the association between genetically predicted PCOS and ovarian cancer risk, overall and by histotype, using summary statistics from a previously conducted genome-wide association study (GWAS) of ovarian cancer among European ancestry women within the OCAC (22 406 with invasive disease, 3103 with borderline disease and 40 941 controls).

RESULTS

An inverse association was observed between genetically predicted PCOS and invasive ovarian cancer risk: odds ratio (OR)=0.92 [95% confidence interval (CI)=0.85-0.99; P = 0.03]. When results were examined by histotype, the strongest inverse association was observed between genetically predicted PCOS and endometrioid tumors (OR = 0.77; 95% CI = 0.65-0.92; P = 0.003). Adjustment for individual-level body mass index, oral contraceptive use and parity did not materially change the associations.

CONCLUSION

Our study provides evidence for a relationship between PCOS and reduced ovarian cancer risk, overall and among specific histotypes of invasive ovarian cancer. These results lend support to our previous observational study results. Future studies are needed to understand mechanisms underlying this association.

Multi-Systemic Biological Risk and Cancer Mortality: The NHANES III Study

Multi-systemic biological risk (MSBR), a proxy for allostatic load, is a composite index of biomarkers representing dysregulation due to responses to chronic stress. This study examined the association of an MSBR index with cancer mortality. The sample included n = 13,628 adults aged 20–90 from the NHANES III Linked Mortality File (1988–1994). The MSBR index included autonomic (pulse rate, blood pressure), metabolic (HOMA_ir, triglycerides, waist circumference), and immune (white blood cell count, C-reactive protein) markers. We fit Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CI) of overall cancer mortality risk, according to quartiles (q) of the index. In multivariable models, compared to those in q1, q4 had a 64% increased risk for cancer mortality (HR = 1.64, 95% CI:1.13–2.40). The immune domain drove the association (HR per unit = 1.19, 95% CI:1.07–1.32). In stratified analyses, the HR for those with a BMI ≥ 25 was 1.12 per unit (95% CI:1.05–1.19) and those with a BMI < 25 was 1.04 per unit (95% CI:0.92–1.18). MSBR is positively associated with risk for cancer mortality in a US sample, particularly among those who are overweight or obese. The utilization of standard clinical measures comprising this index may inform population cancer prevention strategies.

A network analysis to identify mediators of germline-driven differences in breast cancer prognosis

Identifying the underlying genetic drivers of the heritability of breast cancer prognosis remains elusive. We adapt a network-based approach to handle underpowered complex datasets to provide new insights into the potential function of germline variants in breast cancer prognosis. This network-based analysis studies ~7.3 million variants in 84,457 breast cancer patients in relation to breast cancer survival and confirms the results on 12,381 independent patients. Aggregating the prognostic effects of genetic variants across multiple genes, we identify four gene modules associated with survival in estrogen receptor (ER)-negative and one in ER-positive disease. The modules show biological enrichment for cancer-related processes such as G-alpha signaling, circadian clock, angiogenesis, and Rho-GTPases in apoptosis.

A California Cancer Registry Analysis of Urothelial and Non-urothelial Bladder Cancer Subtypes: Epidemiology, Treatment, and Survival

INTRODUCTION

We evaluated epidemiologic trends and survival for bladder cancer histologic subtypes in California patients by comparing urothelial carcinoma of the bladder (UCB) and non-urothelial subtypes including squamous cell carcinoma (SCC), adenocarcinoma (ADC), and small-cell carcinoma (SmCC).

MATERIALS AND METHODS

The California Cancer Registry (CCR) was queried for incident bladder cancer cases from 1988 to 2012. Epidemiologic trends based on tumor histology were described. The primary outcome was disease-specific survival (DSS). Kaplan-Meier and multivariable Cox regression survival analyses were performed.

RESULTS

A total of 72,452 bladder cancer cases (66,260 UCB, 1390 SCC, 587 ADC, 370 SmCC, and 3845 other) were included. The median age was 72 years (range, 18-109 years). ADC was more common in younger patients. Male:female ratios varied among cancer types (3.1:1 in UCB, 2.9:1 in SmCC, 1.6:1 in ADC, and 0.9:1 in SCC). Most non-urothelial cases (> 60%) presented at advanced stages, whereas most UCB cases (80.6%) were localized. Kaplan-Meier analysis revealed the best 5-year DSS and overall survival (OS) in UCB, whereas the worst outcomes were seen with SCC and SmCC (P < .0001). Multivariable analysis controlling for age, gender, tumor stage, and grade demonstrated that non-urothelial histologic subtypes were associated with significantly worse DSS compared with UCB (SCC hazard ratio [HR], 2.612; SmCC HR, 1.641; and ADC HR, 1.459; P < .0001).

CONCLUSIONS

Non-urothelial bladder cancers have worse oncologic outcomes than UCB in California patients. SCC and SmCC are associated with the worst DSS based on univariable and multivariable analyses.

The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer

Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM -/- patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors.

Publisher Correction: Shared heritability and functional enrichment across six solid cancers

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Two truncating variants in FANCC and breast cancer risk

Fanconi anemia (FA) is a genetically heterogeneous disorder with 22 disease-causing genes reported to date. In some FA genes, monoallelic mutations have been found to be associated with breast cancer risk, while the risk associations of others remain unknown. The gene for FA type C, FANCC, has been proposed as a breast cancer susceptibility gene based on epidemiological and sequencing studies. We used the Oncoarray project to genotype two truncating FANCC variants (p.R185X and p.R548X) in 64,760 breast cancer cases and 49,793 controls of European descent. FANCC mutations were observed in 25 cases (14 with p.R185X, 11 with p.R548X) and 26 controls (18 with p.R185X, 8 with p.R548X). There was no evidence of an association with the risk of breast cancer, neither overall (odds ratio 0.77, 95%CI 0.44-1.33, p = 0.4) nor by histology, hormone receptor status, age or family history. We conclude that the breast cancer risk association of these two FANCC variants, if any, is much smaller than for BRCA1, BRCA2 or PALB2 mutations. If this applies to all truncating variants in FANCC it would suggest there are differences between FA genes in their roles on breast cancer risk and demonstrates the merit of large consortia for clarifying risk associations of rare variants.

Racial and Socioeconomic Disparities in Bladder Cancer Survival: Analysis of the California Cancer Registry

PURPOSE

To examine the California Cancer Registry (CCR) for bladder cancer survival disparities based on race, socioeconomic status (SES), and insurance in California patients.

PATIENTS AND METHODS

The CCR was queried for bladder cancer cases in California from 1988 to 2012. The primary outcome was disease-specific survival (DSS), defined as the time interval from date of diagnosis to date of death from bladder cancer. Survival analyses were performed to determine the prognostic significance of racial and socioeconomic factors.

RESULTS

A total of 72,452 cases were included (74.5% men, 25.5% women). The median age was 72 years (range, 18-109 years). The racial distribution among the patients was 81% white, 3.8% black, 8.8% Hispanic, 5.2% Asian, and 1.2% from other races. In black patients, tumors presented more frequently with advanced stage and high grade. Medicaid patients tended to be younger and had more advanced-stage, higher-grade tumors compared to patients with Medicare or managed care (P < .0001). Kaplan-Meier analysis demonstrated significantly poorer 5-year DSS in black, low SES, and Medicaid patients (P < .0001). When controlling for stage, grade, age, and gender, multivariate analysis revealed that black race (DSS hazard ratio = 1.295; 95% confidence interval, 1.212-1.384), low SES (DSS hazard ratio = 1.325; 95% confidence interval, 1.259-1.395), and Medicaid insurance (DSS hazard ratio = 1.349; 95% confidence interval, 1.246-1.460) were independent prognostic factors (P < .0001).

CONCLUSION

An analysis of the CCR demonstrated that black race, low SES, and Medicaid insurance portend poorer DSS. These findings reflect a multifaceted socioeconomic and public health conundrum, and efforts to reduce inequalities should be pursued.

Feasibility of visual inspection with acetic acid (VIA) screening for cervical cancer in Tanzania with emphasis on special populations

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Background: Following the report that VIA screening reduced cervical cancer mortality by 31% in India (ASCO LBA2 2013; Shastri SS, et al JNCI 2014), the W.H.O. endorsed VIA guidelines for Africa, where the global disease burden is highest. In Tanzania, cervical cancer is a major source of morbidity and mortality, with nearly 10,000 new cases and 7,000 deaths annually. Due to lack of resources, therapies are limited and patient outcomes are further confounded by the relatively high prevalence of concurrent HIV infection. We report on the feasibility of VIA screening in Tanzania with emphasis on unique populations. Methods: Our two 5-day VIA screen-and-treat workshops in Buzuruga and Sangabuye Health Centres in Mwanza, Tanzania were approved by the University of California, Irvine IRB and local health authorities. Participants were recruited from surrounding communities and offered free cervical VIA screening, cryotherapy when indicated, and HIV rapid testing. Acetowhite lesions and/or abnormal vascular markings were VIA+. Chi-square and Fisher exact tests were performed with statistical significance assigned at 0.05. Results: During July 2018, 825 of 917 registered participants underwent VIA screening and 25.1% (n=207) were VIA+. 147 VIA+ non-pregnant women received same day cryotherapy and 15 (1.8%) with lesions suspicious for cancer were referred to Bugando Medical Center. In the subanalysis of 64 HIV+ patients (23 diagnosed at the workshops, 41 with prior diagnosis on ART), HIV infection was not associated with VIA positivity (p=0.497). Additionally, a non-significant trend of higher VIA+ screens among newly diagnosed untreated HIV patients (27.7%) vs patients with known HIV on ART (17.5%) was observed (p=0.556). Conclusions: VIA screening for cervical cancer, while feasible in Tanzania, will require follow-up and repetitive screening. Although cervical cancer is an AIDS-defining illness, lack of correlation between HIV infection and VIA-positivity may reflect the availability of W.H.O.-subsidized ART in sub-Saharan Africa to attenuate HPV-mediated neoplastic transformation, as previously reported by others. Further study of this phenomenon is warranted.

Evaluation of vitamin D biosynthesis and pathway target genes reveals UGT2A1/2 and EGFR polymorphisms associated with epithelial ovarian cancer in African American Women

An association between genetic variants in the vitamin D receptor (VDR) gene and epithelial ovarian cancer (EOC) was previously reported in women of African ancestry (AA). We sought to examine associations between genetic variants in VDR and additional genes from vitamin D biosynthesis and pathway targets (EGFR, UGT1A, UGT2A1/2, UGT2B, CYP3A4/5, CYP2R1, CYP27B1, CYP24A1, CYP11A1, and GC). Genotyping was performed using the custom-designed 533,631 SNP Illumina OncoArray with imputation to the 1,000 Genomes Phase 3 v5 reference set in 755 EOC cases, including 537 high-grade serous (HGSOC), and 1,235 controls. All subjects are of African ancestry (AA). Logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (CI). We further evaluated statistical significance of selected SNPs using the Bayesian False Discovery Probability (BFDP). A significant association with EOC was identified in the UGT2A1/2 region for the SNP rs10017134 (per allele OR = 1.4, 95% CI = 1.2-1.7, P = 1.2 × 10-6 , BFDP = 0.02); and an association with HGSOC was identified in the EGFR region for the SNP rs114972508 (per allele OR = 2.3, 95% CI = 1.6-3.4, P = 1.6 × 10-5 , BFDP = 0.29) and in the UGT2A1/2 region again for rs1017134 (per allele OR = 1.4, 95% CI = 1.2-1.7, P = 2.3 × 10-5 , BFDP = 0.23). Genetic variants in the EGFR and UGT2A1/2 may increase susceptibility of EOC in AA women. Future studies to validate these findings are warranted. Alterations in EGFR and UGT2A1/2 could perturb enzyme efficacy, proliferation in ovaries, impact and mark susceptibility to EOC.

A comprehensive gene-environment interaction analysis in Ovarian Cancer using genome-wide significant common variants

As a follow-up to genome-wide association analysis of common variants associated with ovarian carcinoma (cancer), our study considers seven well-known ovarian cancer risk factors and their interactions with 28 genome-wide significant common genetic variants. The interaction analyses were based on data from 9971 ovarian cancer cases and 15,566 controls from 17 case-control studies. Likelihood ratio and Wald tests for multiplicative interaction and for relative excess risk due to additive interaction were used. The top multiplicative interaction was noted between oral contraceptive pill (OCP) use (ever vs. never) and rs13255292 (p value = 3.48 × 10-4 ). Among women with the TT genotype for this variant, the odds ratio for OCP use was 0.53 (95% CI = 0.46-0.60) compared to 0.71 (95%CI = 0.66-0.77) for women with the CC genotype. When stratified by duration of OCP use, women with 1-5 years of OCP use exhibited differential protective benefit across genotypes. However, no interaction on either the multiplicative or additive scale was found to be statistically significant after multiple testing correction. The results suggest that OCP use may offer increased benefit for women who are carriers of the T allele in rs13255292. On the other hand, for women carrying the C allele in this variant, longer (5+ years) use of OCP may reduce the impact of carrying the risk allele of this SNP. Replication of this finding is needed. The study presents a comprehensive analytic framework for conducting gene-environment analysis in ovarian cancer.

Genome-wide association and transcriptome studies identify target genes and risk loci for breast cancer

Genome-wide association studies (GWAS) have identified more than 170 breast cancer susceptibility loci. Here we hypothesize that some risk-associated variants might act in non-breast tissues, specifically adipose tissue and immune cells from blood and spleen. Using expression quantitative trait loci (eQTL) reported in these tissues, we identify 26 previously unreported, likely target genes of overall breast cancer risk variants, and 17 for estrogen receptor (ER)-negative breast cancer, several with a known immune function. We determine the directional effect of gene expression on disease risk measured based on single and multiple eQTL. In addition, using a gene-based test of association that considers eQTL from multiple tissues, we identify seven (and four) regions with variants associated with overall (and ER-negative) breast cancer risk, which were not reported in previous GWAS. Further investigation of the function of the implicated genes in breast and immune cells may provide insights into the etiology of breast cancer.

Abstract P3-01-16: Micro-cavity array system for size-based enrichment of circulating tumor cells and circulating cancer associated fibroblasts from blood of patients with breast cancer

Background:Circulating Tumor Cells(CTCs) have prognostic implications in patients with metastatic breast cancer(MBC).During the Epithelial Mesenchymal Transition(EMT), CTCs acquire a more mesenchymal phenotype. Hence, methodologies such as the Cell search that rely on the expression of an epithelial marker EpCAM in CTCs fail to capture a subset of CTCs undergoing the process of EMT and therefore do not adequately represent the true circulatory metastatic load. Hitachi chemicals has invented a size based micro cavity array (MCA) system that allows for the isolation of tumor cells based on the differences in size and deformability between tumor and blood cells. Photolithography and the metal plating can precisely control the filter pore size of our system. Our platform is more sensitive than the Cell Search method in detecting CTCs in Lung Cancer. Cancer Associated Fibroblasts (CAFs) are a major component of the breast tumor microenvironment. Using a micro filter capture technique, our co-authors have demonstrated that CAFs can be enumerated as circulating CAFs (cCAFs). Hitachi's Micro cavity Array System has not been evaluated in the detection of CTCs and cCAFs in patients with Breast Cancer. The purpose of this study is to demonstrate that CTCs and cCAFs can be enumerated using our platform and the cCAFs can serve as biomarkers of metastasis simultaneously with CTCs.

Method:We undertook a Pilot study of 20 patients each with breast cancer across Stage I, Stage II, Stage III and Stage IV. A total of 10ml of peripheral blood was obtained from each patient. Enumeration of CTCs and cCAFs was carried out by the size based mircocavity array system invented by Hitachi Chemicals. Identification of these cells was done by a triple Immunofluorescence staining for pan-CK (cytokeratin), FAP (Fibroblast Activated Protein) and CD45. CTCs were identified as CK+, CD45-, FAP- cells and cCAFs were identified as FAP+, CK- and CD 45 negative cells.

Result:Our method had a high cell recovery rate (90%or higher) and efficient white blood cells depletion rate (99.99%). We present the data from a total of 13 patients in this abstract, (two with stage III and eleven with stage IV breast cancer) . Data from rest of the subjects will be presented at the actual meeting. We detected the presence of CTCs in 11/11(100%) in patients with stage IV(mean of 44) and in 2 out of 2 (100%) patients with Stage III Breast Cancer. We detected the presence of cCAFs in 1 out of 2 patients( 50%) with stage III and in 8 of 11(81.8%) (mean of 9)patients with stage IV breast cancer( Fisher's exact test p-value= 0.42). The number of CTCs and cCAFs was significantly elevated in patients with MBC and the number was clinically associated with a high metastatic burden.

Conclusions:CTCs and cCAFs can be enumerated using a size based size based micro cavity array invented by Hitachi Chemicals that does not rely on the expression of epithelial markers in CTCs. CTCs and cCAFs can be detected in patients with stage III and stage IV breast cancer. CTCs and cCAFs were associated with high metastatic burden and their numbers were significantly elevated in patients with MBC. cCAFs could serve as biomarkers alongside of CTCs in MBC.

Citation Format: Parajuli R, Ly R, Ziogas A, Eapen A, Lane K, Chen J, Lin E, Mehta R, Tsai A. Micro-cavity array system for size-based enrichment of circulating tumor cells and circulating cancer associated fibroblasts from blood of patients with breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-01-16.

Shared heritability and functional enrichment across six solid cancers

Quantifying the genetic correlation between cancers can provide important insights into the mechanisms driving cancer etiology. Using genome-wide association study summary statistics across six cancer types based on a total of 296,215 cases and 301,319 controls of European ancestry, here we estimate the pair-wise genetic correlations between breast, colorectal, head/neck, lung, ovary and prostate cancer, and between cancers and 38 other diseases. We observed statistically significant genetic correlations between lung and head/neck cancer (rg = 0.57, p = 4.6 × 10-8), breast and ovarian cancer (rg = 0.24, p = 7 × 10-5), breast and lung cancer (rg = 0.18, p =1.5 × 10-6) and breast and colorectal cancer (rg = 0.15, p = 1.1 × 10-4). We also found that multiple cancers are genetically correlated with non-cancer traits including smoking, psychiatric diseases and metabolic characteristics. Functional enrichment analysis revealed a significant excess contribution of conserved and regulatory regions to cancer heritability. Our comprehensive analysis of cross-cancer heritability suggests that solid tumors arising across tissues share in part a common germline genetic basis.