Trends in Utilization and Medicare Spending on Short-Course Radiation Therapy for Breast and Prostate Cancer: An Episode-Based Analysis From 2015 to 2019

PURPOSE

Evidence supports the value of shorter, similarly efficacious, and potentially more cost-effective hypofractionated radiation therapy (RT) regimens in many clinical scenarios for breast cancer (BC) and prostate cancer (PC). However, practice patterns vary considerably. We used the most recent Centers for Medicare and Medicaid Services data to assess trends in RT cost and practice patterns among episodes of BC and PC.

METHODS AND MATERIALS

We performed a retrospective cohort analysis of all external beam RT episodes for BC and PC from 2015 to 2019 to assess predictors of short-course RT (SCRT) use and calculated spending differences. Multivariable logistic regression defined adjusted odds ratios of receipt of SCRT over longer-course RT (LCRT) by treatment modality, age, year of diagnosis, type of practice, and the interaction between year and treatment setting. Medicare spending was evaluated using multivariable linear regression controlling for duration of RT regimen (SCRT vs LCRT) in addition to the above covariables.

RESULTS

Of 143,729 BC episodes and 114,214 PC episodes, 63,623 (44.27%) and 25,955 (22.72%) were SCRT regimens, respectively. Median total spending for SCRT regimens among BC episodes was $9418 (interquartile range [IQR], $7966-$10,983) versus $13,602 (IQR, $11,814-$15,499) for LCRT. Among PC episodes, median total spending was $6924 (IQR, $4,509-$12,905) for stereotactic body RT, $18,768 (IQR, $15,421-$20,740) for moderate hypofractionation, and $27,319 (IQR, $25,446-$29,421) for LCRT. On logistic regression, receipt of SCRT was associated with older age among both BC and PC episodes as well as treatment at hospital-affiliated over freestanding sites (P < .001 for all).

CONCLUSIONS

In this evaluation of BC and PC RT episodes from 2015 to 2019, we found that shorter-course RT resulted in lower costs than longer-course RT. SCRT was also more common in hospital-affiliated sites. Future research focusing on potential payment incentives encouraging SCRT when clinically appropriate in the 2 most common cancers treated with RT will be valuable as the field continues to prospectively evaluate cost-effective hypofractionation in other disease sites.

Disparities in Stage at Presentation Among Hispanic and Latinx Patients With Non-Small-Cell Lung Cancer in the United States

PURPOSE

Hispanic and Latinx people in the United States are the fastest-growing ethnic group. However, previous studies in non-small-cell lung cancer (NSCLC) often analyze these diverse communities in aggregate. We aimed to identify differences in NSCLC stage at diagnosis in the US population, focusing on disaggregated Hispanic/Latinx individuals.

METHODS

Data from the National Cancer Database from 2004 to 2018 identified patients with primary NSCLC. Individuals were disaggregated by racial and ethnic subgroup and Hispanic country of origin. Ordinal logistic regression adjusting for age, facility type, income, educational attainment, comorbidity index, insurance, and year of diagnosis was used to create adjusted odds ratios (aORs), with higher odds representing diagnosis at later-stage NSCLC.

RESULTS

Of 1,565,159 patients with NSCLC, 46,616 were Hispanic/Latinx (3.0%). When analyzed in the setting of race and ethnicity, Hispanic patients were more likely to be diagnosed with metastatic disease compared with non-Hispanic White (NHW) patients: 47.0% for Hispanic Black, 46.0% Hispanic White, and 44.3% of Hispanic other patients versus 39.1% of non-Hispanic White patients (P < .001 for all). By country of origin, 51.4% of Mexican, 41.7% of Puerto Rican, 44.6% of Cuban, 50.8% of South or Central American, 48.4% of Dominican, and 45.6% of other Hispanic patients were diagnosed with metastatic disease, compared with 39.1% of NHWs. Conversely, 20.2% of Mexican, 26.9% of Puerto Rican, 24.2% of Cuban, 22.5% of South or Central American, 23.7% of Dominican, and 24.5% of other Hispanic patients were diagnosed with stage I disease, compared with 30.0% of NHWs. All Hispanic groups were more likely to present with later-stage NSCLC than NHW patients (greatest odds for Mexican patients, aOR, 1.44; P < .001).

CONCLUSION

Hispanic/Latinx patients with non-small-cell lung cancer were more likely to be diagnosed with advanced disease compared with NHWs. Disparities persisted upon disaggregation by both race and country of origin, with over half of Mexican patients with metastatic disease at diagnosis. Disparities among Hispanic/Latinx groups by race and by country of origin highlight the shortcomings of treating these groups as a monolith and underscore the need for disaggregated research and targeted interventions.

Adding a Coefficient for Race to the 4Kscore Improves Calibration for Black Men

PURPOSE

Black men face a higher incidence of high-risk prostate cancer (PCa) compared with non-Black men. While the 4Kscore is a widely utilized commercial test for PCa risk assessment, it does not currently account for racial differences. The aim of this study is to describe and validate a prespecified race coefficient for the 4Kscore with the goal of improving the accuracy of this test for Black men.

MATERIALS AND METHODS

Using data from 85 Black men from the initial US prospective validation study, a race coefficient of 0.6 on the log-odds scale was prespecified. We calculated discrimination, calibration, and clinical utility of the 4Kscore with and without this coefficient for Black race in our primary analysis cohort of 205 Black men undergoing biopsy for PCa in a Veterans Affairs (VA) institution. We performed a sensitivity analysis using a combined cohort from the US prospective validation and the VA studies.

RESULTS

The mean probability of high-grade PCa from the 4Kscore in the primary cohort increased from 25% to 37% with race coefficient addition. Incorporating the race coefficient improved 4Kscore's calibration in Black men, with consequent improvements in clinical utility based on decision curve analysis. Model discrimination was maintained (AUC 0.825 vs 0.828, P = .14) in the combined cohort of Black and non-Black men from the US prospective and VA studies and the calibration remained largely unchanged.

CONCLUSIONS

Incorporating a prespecified coefficient for Black race improved calibration and clinical utility of the 4Kscore among Black men and should be added to the 4Kscore.

The Molecular, Immunologic, and Clinicodemographic Landscape of MYC-Amplified Advanced Prostate Cancer

BACKGROUND

MYC is a commonly amplified, potentially targetable gene in prostate cancer (PCa). We sought to define the molecular, immunologic, and clinicodemographic landscape of MYC amplification (MYCamp) in advanced PCa to establish a rationale for personalized treatment combinations.

METHODS

Hybrid capture-based comprehensive genomic profiling (CGP) was performed on PCa tumor samples. MYCamp = copy number ≥6 (CN). Patients treated between January 2011 and December 2020 were selected from a nationwide deidentified (280 clinics) EHR-derived clinicogenomic database (CGDB).

RESULTS

Of 12,528 hormone-sensitive and castrate-resistant (CRPC) samples, MYCamp was detected in 10.6% (median CN = 8). MYCamp was more frequent in men with African versus European ancestry (12.9% vs. 10.2% P = .002), in metastatic vs. primary tissue (15.7% vs. 6.2% P < .001), and enriched in metastatic liver lesions (20.2%), but inversely associated with high microsatellite-instability (0.8% vs. 2.4%, P < .001). MYC CN≥15 was associated with PD-L1 expression (26.1% vs. 9.8%, P = .025). Amplification of AR, RAD21, LYN, CCND1, ZNF703, FGF3/4/19, and FGFR1 was enriched in MYCamp vs. MYCwt (all P < .001). In liquid samples with tumor fraction [TF]>0, MYCamp was detected in 2.0% (28/1,402), and 4.5% (20/445) with TF>20%. In the CGDB, (67 MYCamp and 658 MYCwt), patients received similar treatments; most received hormone therapies (35.8% MYCamp vs. 31.5% MYCwt) or chemotherapy (37.3% MYCamp vs. 27.7% MYCwt) as first therapy after CGP report.

CONCLUSION

MYCamp defines a biologically distinct subset of PCa patients and is characterized with multiple proxies of advanced disease. These data suggest that MYCamp may be prognostic; independent cohorts are needed to validate these findings.

Mortality Risk for Docetaxel-Treated, High-Grade Prostate Cancer With Low PSA Levels: A Meta-Analysis

Importance

Patients with high-grade prostate cancer with low levels of prostate-specific antigen (PSA; <4 ng/mL) are at high risk of mortality, necessitating an improved treatment paradigm.

Objective

To assess for these patients whether adding docetaxel to standard of care (SOC) treatment is associated with decreased prostate cancer-specific mortality (PCSM) and all-cause mortality (ACM).

Data Sources

PubMed search from 2000 to 2022.

Study Selection

Five prospective randomized clinical trials (RCTs) performed in the US, France, and the United Kingdom evaluating SOC treatment with radiotherapy and androgen deprivation therapy (ADT) or with radical prostatectomy vs SOC plus docetaxel.

Data Extraction and Synthesis

Individual data were included from patients with nonmetastatic prostate cancer, a PSA level of less than 4 ng/mL, and a Gleason score of 8 to 10. Patients initiated treatment between February 21, 2006, and December 31, 2015 (median follow-up, 7.1 [IQR, 5.4-9.9] years). Data were analyzed on December 16, 2022.

Main Outcomes and Measures

Hazard ratio (HR) of ACM and subdistribution HR (sHR) of PCSM adjusted for performance status (1 vs 0 or good health), Gleason score (9 or 10 vs 8), tumor category (T3-T4 vs T1-T2 or TX), and duration of ADT (2 years vs 4-6 months).

Results

From a cohort of 2184 patients, 145 patients (6.6%) in 4 RCTs were eligible (median age, 63 [IQR, 46-67] years). Thirty-one patients died, and of these deaths, 22 were due to prostate cancer. Performance status was 0 for 139 patients (95.9%) and 1 for 6 patients (4.1%). A reduced but nonsignificant risk of ACM (HR, 0.51 [95% CI, 0.24-1.09]) and PCSM (sHR, 0.42 [95% CI, 0.17-1.02]) was associated with patients randomized to SOC plus docetaxel compared with SOC. The risk reduction in ACM (HR, 0.46 [95% CI, 0.21-1.02]) was more pronounced among patients with a performance status of 0 and was significant for PCSM (sHR, 0.30 [95% CI, 0.11-0.86]).

Conclusions and Relevance

Adding docetaxel to SOC treatment for patients who are in otherwise good health with a PSA level of less than 4 ng/mL and a Gleason score of 8 to 10 was associated with a significant reduction in PCSM and therefore has the potential to improve prognosis.

Genomic Characterization of Aggressive Breast Cancer in Younger Women

PURPOSE

Although breast cancer (BC) risk increases with age, BC in younger women is more aggressive with higher mortality compared with older women. We characterize the genomic landscape of BCs in younger women.

METHODS

Clinicopathologic, molecular, and genomic differences across age groups (< 40 years, 40-60 years, > 60 years) in female BC patients were investigated in two large cohorts [AACR-GENIE8.1 (n = 11,594) and METABRIC (n = 2509)]. Cox-proportional regression analyzed the prognostic impact of age groups for disease-specific survival (DSS) and recurrence-free survival (RFS) in METABRIC and progression-free survival (PFS) in GENIE cohorts. Chi-squared test was used to assess statistical associations between genomic alterations and age groups.

RESULTS

Survival analysis showed that women < 40 years had shorter DSS [hazard ratio (HR): 1.52, p = 0.005], RFS (HR: 1.4, p = 0.006), and PFS (HR: 1.82, p = 0.0003) compared with women 40-60 years, and shorter RFS (HR: 1.5, p = 0.001) and PFS (HR: 2.95, p < 0.0001) compared with women > 60 years. Molecular subtypes in the METABRIC cohort showed women < 40 years were enriched with basal, and HER2+ subtypes, and less enriched with luminal A and B subtype (p < 0.0001). Characterization of genomic alterations in both cohorts demonstrated that BCs in women < 40 years were more enriched with TP53 mutations (FDR < 0.0001), BRCA1 mutations (FDR = 0.01), ERBB2 amplifications (FDR < 0.001), CDK12 amplifications (FDR < 0.001), and PPM1D amplifications (FDR < 0.001). In contrast, BCs in older women (> 60 years) were more enriched with PIK3CA, KMT2C, and CDH1 mutations (FDR < 0.0001).

CONCLUSIONS

BCs in young women are associated with shorter survival and more aggressive genomic features, including mutations in TP53 and BRCA1, and amplifications in ERBB2 and CDK12. These findings have the potential to impact clinical trial design and treatment.

Unique Spectrum of Activating BRAF Alterations in Prostate Cancer

PURPOSE

Alterations in BRAF have been reported in 3% to 5% of prostate cancer, although further characterization is lacking. Here, we describe the nature of BRAF alterations in prostate cancer using a large cohort from commercially available tissue and liquid biopsies subjected to comprehensive genomic profiling (CGP).

EXPERIMENTAL DESIGN

Tissue and liquid biopsies from patients with prostate cancer were profiled using FoundationOne CDx and FoundationOne Liquid CDx CGP assays, respectively. Tissue biopsies from non-prostate cancer types were used for comparison (n = 275,151). Genetic ancestry was predicted using a single-nucleotide polymorphism (SNP) based approach.

RESULTS

Among 15,864 tissue biopsies, BRAF-activating alterations were detected in 520 cases (3.3%). The majority (463 samples, 2.9%) harbored class II alterations, including BRAF rearrangements (243 samples, 1.5%), K601E (101 samples, 0.6%), and G469A (58 samples, 0.4%). BRAF-altered prostate cancers were enriched for CDK12 mutations (OR, 1.87; 9.2% vs. 5.2%; P = 0.018), but depleted in TMPRSS2 fusions (OR, 0.25; 11% vs. 32%; P < 0.0001), PTEN alterations (OR, 0.47; 17% vs. 31%; P < 0.0001), and APC alterations (OR, 0.48; 4.4% vs. 8.9%; P = 0.018) relative to BRAF wild-type (WT) disease. Compared with patients of European ancestry, BRAF alterations were more common in tumors from patients of African ancestry (5.1% vs. 2.9%, P < 0.0001) and Asian ancestry (6.0% vs. 2.9%, P < 0.001).

CONCLUSIONS

Activating BRAF alterations were detected in approximately 3% of prostate cancers, and most were class II mutations and rearrangements; BRAF V600 mutations were exceedingly rare. These findings suggest that BRAF activation in prostate cancer is unique from other cancers and supports further clinical investigation of therapeutics targeting the mitogen-activated protein kinase (MAPK) pathway.

Trends in Utilization and Medicare Spending on Shorter vs. Longer Radiotherapy Courses for Breast and Prostate Cancer

PURPOSE/OBJECTIVE(S)

Evidence based research supports shorter, similarly efficacious, and potentially more cost-effective hypofractionated treatment regimens in many clinical scenarios for breast cancer (BC) and prostate cancer (PC). However, practice patterns of hospital-affiliated and standalone facilities vary considerably. We used the most recent Centers for Medicare and Medicaid Services data to assess trends in radiotherapy (RT) costs and practice patterns among episodes of BC and PC.

MATERIALS/METHODS

We performed a retrospective cohort analysis of all external beam episodes for BC and PC from 2015-2019. For patients with BC, receipt of shorter-course RT (SCRT) was defined as receiving 11-20 fractions of external beam radiation therapy (including IMRT), and conventional RT as >20 fractions. For patients with PC, SBRT was defined as receipt of <10 fractions and moderate hypofractionation as 10-30 fractions (SCRT defined as SBRT and moderate hypofractionation), and >30 fractions for conventional RT. Total Medicare spending were defined as the sum of winsorized payment for professional and technical services furnished during the episode in 2019 dollars. Multivariable logistic regression defined adjusted odds ratios (ORs) of receipt of SCRT over conventional RT by treatment modality, age, year of diagnosis, type of practice, as well as a time*treatment setting interaction term. Medicare spending was evaluated using multivariable linear regression controlling for duration of RT regimen (SCRT vs conventional) in addition to the covariables above.

RESULTS

Of 47,283 BC episodes and 45,917 PC episodes, 23,705 (50.13%) and 9,125 (19.87%) were SCRT, respectively. Median total spending for SCRT among BC episodes was $9,324 (IQR, $7,916-$10,921) vs. $13,372 (IQR, $11,511-$15,283) for conventional RT. Among PC episodes, median total spending was $12,917 (IQR, $9,551-$15,271) for SBRT, $18,944 (IQR, $16,530-$20,615) for moderate hypofractionation, and $26,935 (IQR, $25,062-$28,959) for conventional RT. For both cancers, total episode spending was reduced with SCRT utilization [(BC adjusted β, -$4,200; p<0.001), (PC adjusted β, -$8,747; p<0.001)], older age, and non-IMRT-based treatment. On logistic regression, receipt of SCRT was associated with older age among both BC and PC episodes (p<0.001), as well as treatment at hospital-affiliated over freestanding sites [(BC OR [95% CI], 1.41 [1.29-1.54], p<0.001), (PC OR, 1.64 [1.39-1.94], p<0.001)].

CONCLUSION

In this evaluation of all BC and PC RT episodes from 2015-2019, we found that shorter-course RT resulted in increased cost-savings vs. conventional RT. SCRT was also more common in hospital-affiliated sites. Further research is needed to devise payment incentives that encourage SCRT when clinically applicable in the two most common sites treated with RT, and to prospectively study cost-effective hypofractionation in other disease sites.

Impact of Testosterone Recovery on Clinical Outcomes of Patients Treated with Salvage Radiotherapy and Androgen Suppression: A Secondary Analysis of the NRG/RTOG 0534 Sport Phase 3 Trial

PURPOSE/OBJECTIVE(S)

Testosterone (T) kinetics and its relationship with clinical outcomes has not been studied in trials using salvage radiotherapy and androgen deprivation therapy (ADT). We performed a secondary analysis of the NRG Oncology/RTOG 0534 SPPORT trial, which compared prostate bed radiotherapy (PBRT) (arm 1), PBRT + short-term androgen deprivation therapy (ADT) (arm 2), or PBRT + pelvic lymph node radiotherapy (PLNRT) + short-term ADT (arm 3). We assessed longitudinal serum T levels and the impact of testosterone recovery (TR) on clinical outcomes.

MATERIALS/METHODS

ADT was given for 4-6 months in arms 2 and 3, starting 2 months prior to radiotherapy. The trial excluded patients with baseline T < 40% of the lower limit of normal. TR was defined in 3 ways: 1) return to non-castrate level (>50 ng/dL), 2) return to normal level (>300 ng/dL), and 3) return to baseline level. Time to TR was estimated using cumulative incidence and death without an event considered a competing risk. Unadjusted and adjusted hazard ratios and 95% confidence intervals (CIs) were calculated using Cox proportional hazards model. Freedom from progression (FFP) was defined as biochemical failure according to the Phoenix definition (PSA ≥2 ng/mL over the nadir PSA), clinical failure (local, regional, or distant), or death from any cause.

RESULTS

A total of 1699 patients with T at baseline and at least 1 follow-up assessment were included. The median age was 64 years (IQR 59 - 69), 12.8% were black, 14.9% had diabetes, and 54.1% were former or current smokers. Median baseline T in arms 1, 2 and 3 was 320 ng/dL (IQR 239 - 424), 319 ng/dL (IQR 237 - 438) and 330 ng/dL (IQR 252 - 446), respectively. At 6 months, median T in arms 1, 2 and 3 was 290 ng/dL (IQR 210 - 390), 190.4 ng/dL (IQR 66 - 296) and 191 ng/dL (IQR 40.5 - 313). At 2 years, in arms 2 and 3, TR to non-castrate, normal and baseline levels were 95%, 55% and 23%, respectively. At 5 years, in arms 2 and 3, TR to non-castrate, normal and baseline levels were 98%, 73% and 42%, respectively. FFP was superior in arms 2 and 3 vs. arm 1 in patients with TR by all three definitions. In patients with recovered T to normal levels by 2 years (n = 904), the 5-year FFP rates were 71.8% (95% CI 66.9-76.6) in arm 1, 77.2% (72.1-82.2) in arm 2, and 86.3% (82.3-90.3) in arm 3 (arm 2 vs arm 1: HR 0.74, 95% CI 0.56-0.98, p = 0.034; arm 3 vs arm 1: HR 0.54, 95% CI 0.40-0.72, p<.0001).

CONCLUSION

This work represents the largest study of T kinetics in patients treated with salvage radiation and ADT. Approximately half of patients did not normalize their T levels by 2 years. Our data validate an incremental and meaningful FFP benefit of adding short-term ADT and PLNRT to PBRT independent of T recovery.

Determinants of Widespread Metastases and of Metastatic Tropism in Patients with Prostate Cancer: A Genomic Analysis of Primary and Metastatic Tumors

PURPOSE/OBJECTIVE(S)

A growing body of evidence suggests that metastatic cancer is better described as a spectrum of disease rather than a binarily defined state, ranging from oligometastatic cancer to widespread metastases. Widespread metastases represent the most common cause of cancer-related death among patients with prostate cancer. Therefore, a greater understanding of the genomic features that determine the extent and location of metastatic spread may inform risk stratification, treatment, and monitoring. We identify genomic alterations from primary prostate tumors that are predictive of widespread metastatic potential.

MATERIALS/METHODS

Genomic and clinical data for 1,312 patients with primary prostate adenocarcinomas were extracted from the MSK-MET cohort through cBioPortal. Metastatic site counts and overall survival (OS) data were publicly available for all patients. All samples from primary tumors were profiled using the MSK-IMPACT targeted sequencing platform. Our study focused on 58 genes frequently altered in prostate cancer. Cox proportional hazard analyses defined hazard ratios (HRs) and 95% confidence intervals (CIs) for overall mortality in patients with different metastatic outcomes. Patterns of genomic alterations of the primary tumor associated with metastatic extent and location were compared.

RESULTS

Out of 1,312 patients, 939 (71%) developed metastases, and 113 (8.6%) had metastases to 5 or more distinct anatomical sites (defining wide-spread metastases, WSM). Bone was the most common site of metastasis (36%), and 80% of patients with liver metastases had 4 or more additional sites of metastasis. Among patients with metastases, increasing number of metastatic sites was associated with increased risk of death (HR:1.8, 95% CI:1.63-1.99, p<0.001). To define genomic determinants of WSM, we characterized genomic alterations in 58 prostate cancer related genes. Alterations in the following genes were enriched in tumors from patients with WSM vs others: TP53 mutation (40% vs 20%, p<0.0001), FOXA1-amplification (8% vs 3%, p = 0.02), AR-amplification (4.4% vs 1%, p = 0.01), RB1-deletion (5.3% vs 0.7%, p = 0.001), and BRCA2-deletion (4.4% vs 0.7%, p = 0.01). In a univariable survival analysis, all these alterations were predictive of OS (p<0.05). However, on multivariable analysis, only TP53 mutations, and FOXA1 and AR amplifications were independent prognostic factors. Amplifications of FOXA1 (n = 37) and AR (n = 13) were mutually exclusive (0 overlap), and we found that patients who have either AR or FOXA1 amplifications experienced very poor OS (HR:3.57, 95% CI:2.26-5.6, p p<0.001].

CONCLUSION

We identified genomic alterations (TP53 mutations, FOXA1 and AR amplification, RB1 and BRCA2 deletions) from primary prostate tumors that are predictive of wide-spread metastases and poor outcomes.

Health Equity Achievement in Radiation Therapy (HEART) Score: A Social Prognosis

PURPOSE/OBJECTIVE(S)

The aim of this study was to develop a Health Equity Achievement in Radiation Therapy (HEART) score that can help identify patients at risk of experiencing suboptimal quality-of-care (QoC) early on in the patient-provider encounter and prior to initiation of treatment. Such a score may improve shared decision making to improve QoC.

MATERIALS/METHODS

A retrospective analysis was conducted using the National Cancer Database (NCDB) for prostate cancer cases between 2004-2017. Sociodemographic factors, clinical characteristics, and treatment information were collected. A composite HEART score was built to predict suboptimal QoC, defined as treatment refusal, incomplete treatment, or treatment delay. 70% of the data was allocated to training and 30% to validating a logistic regression model through which a nomogram was constructed.

RESULTS

A total of 1,599,785 patients were included in the analysis, of whom 126,917 (7.9%) had at least one suboptimal QoC. The strongest predictors were Black race, uninsured status, lower educational status, geographic location, and nodal disease (Table). The nomogram demonstrated a fair ability to predict quality metrics, with an area under the receiver operating characteristic curve (AUC) of 0.57 in the test group. The nomogram facilitated graphic interpretation of systemic factors in contributing to suboptimal QoC.

CONCLUSION

With observed potential for predicting suboptimal QoC outcomes in patients with prostate cancer by considering systemic barriers, this NCDB-based nomogram has potential utility as a tool for identifying patients who may benefit from additional social support, including the financial resources associated with these services, to improve access to care. Further validation in diverse datasets is needed to improve performance and generalizability to broader patient populations and different disease sites.

Toxicity Analysis of a Modified Prostate Bed CTV Based on PSMA-PET Patterns of Failure

PURPOSE/OBJECTIVE(S)

After radical prostatectomy (RP), about 20-50% of prostate cancer patients experience biochemical failure, and many can be cured with salvage radiotherapy (sRT). Adding androgen deprivation and pelvic lymph node (PLN) RT to sRT decreases risk of disease progression at the cost of increased toxicity. PSMA PET patterns of local failure after RP show failures outside the RTOG prostate bed CTV (RTOG_CTV) occurring postero-laterally and inferiorly, while in much of the covered bladder local failures are not seen. A modified CTV (m_CTV) encompassing all sites of observed local failures and less of the bladder would potentially reduce dose to the bladder but increase dose to rectum. Herein, we compared sRT plans using RTOG_CTV vs. m_CTV and assessed predicted genitourinary (GU) and gastrointestinal adverse events (AEs).

MATERIALS/METHODS

Volumes for RTOG_CTV, m_CTV, PLN CTV, and OARs were retrospectively contoured on planning CT scans of 28 post-RP patients. Plans were generated for each RTOG_CTV and m_CTV. Doses to prostate bed PTV (CTV + 8mm expansion, 6mm posteriorly) and PLN CTV were 68 Gy and 52.7 Gy, respectively, all in in 34 fractions. Dose-volume histogram (DVH) data for bladder, rectum, and bowel of each plan were extracted. Normal Tissue Complication Probability (NTCP) curves were generated using Lyman-Kutcher-Burman model to predict risk of late G≥3 GU AEs, early GU urgency, leakage, frequency, nocturia, late GI bleed, and late G≥3 GI AEs. Data were compared using 2 sample t-test and Wilcox signed rank test. Correlation of bladder volume and differences in DVH and NTCP data between plans was assessed using Pearson coefficient.

RESULTS

The m_CTV and RTOG_CTV had a median volume of 70.56cc (IQR 59.72-82.17cc) and 132.14cc (IQR 109.33-155.84cc), respectively. Use of m_CTVs resulted in mean absolute decrease of 20.22% and 17.94% in bladder V65 Gy and V40 Gy, respectively (p<0.01 for both), without differences in rectum V65 Gy (p = 0.44), rectum V40 Gy (p = 0.11), or bowel V45 Gy (p = 0.29). Per NTCP curves, m_CTV plans had mean absolute decrease of 24.89% in predicted late G≥3 GU AEs (p<0.01). For predicted early GU AEs, there were mean absolute decreases ranging from 4.85 to 10.21% (p<0.01 for all). Predicted late GI bleed (p = 0.98) and late G≥3 GI AEs (p = 0.99) were not significantly different between plans. When assessed as a continuous variable, smaller bladder volumes had strong correlation with more benefit from m_CTV in bladder V65 Gy (r = -0.71, p<0.01) and moderate correlation with less early GU AEs (r -0.59 to -0.56, p<0.01 for all). There was no correlation with bladder V40 Gy (p = 0.27) or late G≥3 GU AEs (p = 0.14).

CONCLUSION

The m_CTV plans had significantly less dose to the bladder, no increased dose to the rectum and significantly lower predicted rates of early and late GU toxicity. Using a m_CTV encompassing observed local failures from PSMA PET could improve the therapeutic ratio for patients undergoing sRT. Further clinical validation is warranted.

Dose-Volume Parameters to the Urinary Tract Sub-Volumes and Predictors of Genitourinary Acute Toxicity in a Phase 2 Clinical Trial Assessing MRI-Guided Prostate Boost for Localized Prostate Cancer - The Miami BlastM Trial

PURPOSE/OBJECTIVE(S)

The relationship between radiotherapy dose to the sub-volumes of the genitourinary (GU) tract and GU toxicity is poorly understood, particularly in prostate cancer patients treated with an intraprostatic dominant lesion (IDL) boost. While the use of IDL boost improves outcomes, it results in higher doses to GU structures and potentially increased toxicity. We investigated the association between dose-volume histogram (DVH) parameters for urinary tract sub-volumes and GU toxicity in the context of IDL boost in patients enrolled in the Miami BlastM Trial.

MATERIALS/METHODS

DVH data were assessed for patients enrolled in the Miami BlastM, a randomized phase 2 trial (NCT20140627) evaluating upfront versus integrated IDL boost. IDL GTV boost consisted of either 12-14 Gy administered on day 1 or integrated boost of 2.4 Gy per fraction (91.2 Gy total, 98.5 Gy 2.0 Equiv), with the prostate receiving 76 Gy in 38 fractions. Bladder trigone (BTg) and urethra sub-volumes were contoured retrospectively on planning CT scans. GU toxicity was assessed using Common Toxicity Criteria for Adverse Events (CTCAE) version 4 and International Prostate Symptom Score (IPSS). DVHs of the bladder, BTg, bladder minus BTg, prostatic urethra, and bulbomembranous urethra were examined. The primary composite endpoint was CTCAE GU acute toxicity grade (G) ≥2 and/or IPSS increase of ≥10 from baseline. Secondary endpoints were GU acute toxicity G≥2, GU late toxicity G≥2, and IPSS increase of ≥10 from baseline. Univariable and multivariable logistic regression analyses were performed.

RESULTS

A total of 129 patients treated between February 2015 and January 2022 were eligible for analysis. One hundred and one (78%) patients developed either GU acute toxicity G≥2 (68%) and/or an IPSS increase of ≥10 from baseline (30%). Less than 2% of patients developed GU toxicity G≥3. BTg V30 Gy was significantly associated with IPSS increase ≥10 (p = 0.046). The bulbomembranous urethral maximum dose was significantly associated with GU acute toxicity G≥2 and GU late toxicity G≥2 (p <0.05 for both). Average maximum and mean urethral doses were 88.9 and 81.5 Gy, respectively. The BTg maximum dose, V20 Gy, V30 Gy, and V40 Gy were not significantly associated with the primary composite endpoint (p = 0.56, 0.75, 0.89, 0.82, respectively). On multivariable analysis, a higher bulbomembranous urethral maximum dose was significantly associated with GU acute toxicity G≥2 and/or IPSS increase of ≥10 from baseline (p = 0.019).

CONCLUSION

Our data suggest a dose-effect relationship between maximum doses to the bulbomembranous urethra and GU toxicity. A better understanding of RT-related changes to specific sub-volumes of the urethra and strategies to mitigate urethral dose could enhance the therapeutic ratio in prostate cancer patients treated with MRI-guided IDL boost.

Disparities in Time to Prostate Cancer Treatment Initiation before and after the Affordable Care Act

PURPOSE/OBJECTIVE(S)

Delayed access to care may contribute to disparities in prostate cancer (PCa). The Affordable Care Act (ACA) aimed at increasing access and reducing healthcare disparities, but its impact on timely treatment initiation for men with PCa is unknown.

MATERIALS/METHODS

Men with intermediate- and high-risk PCa diagnosed 2010-2016 and treated with curative surgery or radiotherapy were identified in the National Cancer Database. Multivariable logistic regression modeled the effect of race and insurance type on treatment delay >180 days after diagnosis to start of surgery, radiotherapy, or hormonal therapy. Cochran-Armitage test measured annual trends in delays, and join point regression assessed if 2014, the year the ACA became fully operationalized, was significant for inflection in crude rates of major delays.

RESULTS

Of 422,506 eligible men, 18,720 (4.4%) experienced >180-day delay in treatment initiation. Compared to White patients, Black (OR 1.79, 95% CI 1.72-1.87, p<.001) and Hispanic (OR 1.37, 95% CI 1.28-1.48, p<.001) patients had higher odds of delay. These disparities persisted when analyzing only patients treated after 2014 or for patients who had Medicare or Private insurance. Compared to uninsured patients, those with Medicaid had no difference in odds of delay (OR 0.94, 95% CI 0.84-1.06, p = .31), while those with private insurance (OR 0.57, 95% CI 0.52-0.63, p<.001) or Medicare (OR 0.64, 95% CI 0.58-0.70, p<.001) had lower odds of delay. These disparities persisted when analyzing only patients treated after 2014. Mean time to treatment significantly increased from 2010 to 2016 across all racial/ethnic groups (trend p<.001); 2014 was associated with a significant inflection for increase in rates of major delays.

CONCLUSION

The impact of race and insurance status were independently associated with longer delays to PCa treatment in the US. These disparities were unaffected by implementation of the ACA. In fact, implementation of ACA was associated with increased delays in treatment initiation for all men, regardless of race. As the epidemiology of newly diagnosed prostate cancer in the United States continues to shift due to tempered screening and the COVID pandemic, further work will be needed to increase equity in prostate cancer care.

Clinical and Genomic Factors Associated with Greater Tumor Mutational Burden in Prostate Cancer

Tumor mutational burden (TMB) is a biomarker that predicts response to immune checkpoint inhibitor therapy. We currently lack a comprehensive understanding of how genomic and clinical factors correlate with TMB. We used a clinicogenomic database to assess independent predictors of TMB levels. The study included 2740 prostate cancer specimens from prostate gland (51.6%), lymph nodes (14.6%), and bone (10.4%). Androgen deprivation therapy use beyond 24 mo was weakly associated with high TMB (fold-change estimate [FCE] 1.14, 95% confidence interval [CI] 1.03-1.26; p = 0.009). In comparison to the prostate gland, metastases in the bladder (FCE 1.20, 95% CI 1.02-1.42; p = 0.029), liver (FCE 1.26, 95% CI 1.10-1.43; p < 0.001), and other locations (FCE 1.26, 95% CI 1.11-1.43; p < 0.001) were associated with high TMB. Microsatellite instability high (FCE 8.46, 95% CI 6.42-11.15; p < 0.001) and intermediate (FCE 1.77, 95% CI 1.46-2.14; p < 0.001) status were associated with greater TMB. Altered genes associated with greater TMB included MLH1 (FCE 1.81; p = 0.004), MSH2 (FCE 1.87; p < 0.001), MSH6 (FCE 1.92; p < 0.001), BRCA2 (FCE 1.69; p < 0.001), CDK12 (FCE 1.40; p < 0.001), MRE11 (FCE 2.28; p = 0.016), and PALB2 (FCE 2.08; p < 0.001). Our study demonstrates that TMB is relatively stable over lines of therapies and can be used to guide treatment at diagnosis or in later lines for patients with metastatic prostate cancer.

Patient summary

The number of genetic mutations in a tumor (tumor mutational burden, TMB) may help in predicting a patient's response to immunotherapy in advanced prostate cancer. We evaluated clinical and genetic factors that may affect TMB. We found that metastases in the bladder and liver are more likely to have high TMB than the primary tumor. Some individual genes are associated with high TMB. No prior treatment type was strongly associated with TMB, suggesting that TMB can be used to guide treatment at any time point.These data were presented at the American Society of Clinical Oncology 2023 Genitourinary Cancers Symposium.

Colon Cancer Disparities in Stage at Presentation and Time to Surgery for Asian Americans, Native Hawaiians, and Pacific Islanders: A Study with Disaggregated Ethnic Groups

BACKGROUND

Vast differences in barriers to care exist among Asian American, Native Hawaiian, and Pacific Islander (AANHPI) groups and may manifest as disparities in stage at presentation and access to treatment. Thus, we characterized AANHPI patients with stage 0-IV colon cancer and examined differences in (1) stage at presentation and (2) time to surgery relative to white patients.

PATIENTS AND METHODS

We assessed all patients in the National Cancer Database (NCDB) with stage 0-IV colon cancer from 2004 to 2016 who identified as white, Chinese, Japanese, Filipino, Native Hawaiian, Korean, Vietnamese, Laotian, Hmong, Kampuchean, Thai, Asian Indian or Pakistani, and Pacific Islander. Multivariable ordinal logistic regression defined adjusted odds ratios (AORs), with 95% confidence intervals (CI), of (1) patients presenting with advanced stage colon cancer and (2) patients with stage 0-III colon cancer receiving surgery at ≥ 60 days versus 30-59 days versus < 30 days postdiagnosis, adjusting for sociodemographic/clinical factors.

RESULTS

Among 694,876 patients, Japanese [AOR 1.08 (95% CI 1.01-1.15), p < 0.05], Filipino [AOR 1.17 (95% CI 1.09-1.25), p < 0.001], Korean [AOR 1.09 (95% CI 1.01-1.18), p < 0.05], Laotian [AOR 1.51 (95% CI 1.17-1.95), p < 0.01], Kampuchean [AOR 1.33 (95% CI 1.04-1.70), p < 0.01], Thai [AOR 1.60 (95% CI 1.22-2.10), p = 0.001], and Pacific Islander [AOR 1.41 (95% CI 1.20-1.67), p < 0.001] patients were more likely to present with more advanced colon cancer compared with white patients. Chinese [AOR 1.27 (95% CI 1.17-1.38), p < 0.001], Japanese [AOR 1.23 (95% CI 1.10-1.37], p < 0.001], Filipino [AOR 1.36 (95% CI 1.22-1.52), p < 0.001], Korean [AOR 1.16 (95% CI 1.02-1.32), p < 0.05], and Vietnamese [AOR 1.55 (95% CI 1.36-1.77), p < 0.001] patients were more likely to experience greater time to surgery than white patients. Disparities persisted when comparing among AANHPI subgroups.

CONCLUSIONS

Our findings reveal key disparities in stage at presentation and time to surgery by race/ethnicity among AANHPI subgroups. Heterogeneity upon disaggregation underscores the importance of examining and addressing access barriers and clinical disparities.

Disparities in time to prostate cancer treatment initiation before and after the Affordable Care Act

BACKGROUND

Delayed access to care may contribute to disparities in prostate cancer (PCa). The Affordable Care Act (ACA) aimed at increasing access and reducing healthcare disparities, but its impact on timely treatment initiation for PCa men is unknown.

METHODS

Men with intermediate- and high-risk PCa diagnosed 2010-2016 and treated with curative surgery or radiotherapy were identified in the National Cancer Database. Multivariable logistic regression modeled the effect of race and insurance type on treatment delay >180 days after diagnosis. Cochran-Armitage test measured annual trends in delays, and joinpoint regression assessed if 2014, the year the ACA became fully operationalized, was significant for inflection in crude rates of major delays.

RESULTS

Of 422,506 eligible men, 18,720 (4.4%) experienced >180-day delay in treatment initiation. Compared to White patients, Black (OR 1.79, 95% CI 1.72-1.87, p < 0.001) and Hispanic (OR 1.37, 95% CI 1.28-1.48, p < 0.001) patients had higher odds of delay. Compared to uninsured, those with Medicaid had no difference in odds of delay (OR 0.94, 95% CI 0.84-1.06, p = 0.31), while those with private insurance (OR 0.57, 95% CI 0.52-0.63, p < 0.001) or Medicare (OR 0.64, 95% CI 0.58-0.70, p < 0.001) had lower odds of delay. Mean time to treatment significantly increased from 2010 to 2016 across all racial/ethnic groups (trend p < 0.001); 2014 was associated with a significant inflection for increase in rates of major delays.

CONCLUSIONS

Non-White and Medicaid-insured men with localized PCa are at risk of treatment delays in the United States. Treatment delays have been consistently rising, particularly after implementation of the ACA.

Disparities in Diagnosis, Treatment Access, and Time to Treatment Among Hispanic Men With Metastatic Prostate Cancer

PURPOSE

Reporting racial/ethnic disparities in aggregate obscures within-group heterogeneity. We sought to identify disparities in diagnosis and treatment in Hispanic subpopulations with metastatic prostate cancer (mPCa).

METHODS

We disaggregated men with prostate adenocarcinoma from the National Cancer Database from 2004 to 2017 by racial subgroup and Hispanic background. We assessed (1) presenting with mPCa, (2) receiving any treatment, and (3) receiving delayed treatment beyond 90 days. Logistic regression and adjusted odds ratios (aOR) were reported.

RESULTS

Hispanic men had greater odds of presenting with mPCa (aOR, 1.54; 95% CI, 1.50 to 1.58; P < .001) compared with non-Hispanic White (NHW) men. All Hispanic racial subgroups were more likely to present with mPCa, with the highest risk in Hispanic Black (HB) men (aOR, 1.68; 95% CI, 1.46 to 1.93; P < .01). Men from all Hispanic backgrounds had higher odds of presenting with mPCa, especially Mexican men (aOR, 1.99; 95% CI, 1.86 to 2.12; P < .01). Hispanic men were less likely to receive any treatment (aOR, 0.60; 95% CI, 0.53 to 0.67; P < .001), and this effect was particularly strong for Hispanic White patients (aOR, 0.58; 95% CI, 0.52 to 0.66; P < .001) and Dominican men (aOR, 0.52; 95% CI, 0.28 to 0.98; P = .044). Hispanic men were more likely to experience treatment delays compared with NHW men (aOR, 1.38; 95% CI, 1.26 to 1.52; P < .001) and in particular HB (aOR, 1.83; 95% CI, 1.22 to 2.75; P = .002) and South/Central American men (aOR, 1.48; 95% CI, 1.07 to 2.04; P = .018).

CONCLUSION

Differences exist in stage at presentation, treatment receipt, and delays in treatment on disaggregation by racial subgroup and Hispanic heritage. We need to study the potential mechanisms of the observed variations to help develop targeted interventions.

Comprehensive genomic profiling and treatment patterns across ancestries in advanced prostate cancer: a large-scale retrospective analysis

BACKGROUND

Men of African ancestry experience the greatest burden of prostate cancer globally, but they are under-represented in genomic and precision medicine studies. Therefore, we sought to characterise the genomic landscape, comprehensive genomic profiling (CGP) utilisation patterns, and treatment patterns across ancestries in a large, diverse, advanced prostate cancer cohort, to determine the impact of genomics on ancestral disparities.

METHODS

In this large-scale retrospective analysis, the CGP-based genomic landscape was evaluated in biopsy sections from 11 741 patients with prostate cancer, with ancestry inferred using a single nucleotide polymorphism-based approach. Admixture-derived ancestry fractions for each patient were also interrogated. Independently, clinical and treatment information was retrospectively reviewed for 1234 patients in a de-identified US-based clinicogenomic database. Prevalence of gene alterations, including actionable gene alterations, was assessed across ancestries (n=11 741). Furthermore, real-world treatment patterns and overall survival was assessed in the subset of patients with linked clincogenomic information (n=1234).

FINDINGS

The CGP cohort included 1422 (12%) men of African ancestry and 9244 (79%) men of European ancestry; the clinicogenomic database cohort included 130 (11%) men of African ancestry and 1017 (82%) men of European ancestry. Men of African ancestry received more lines of therapy before CGP than men of European ancestry (median of two lines [IQR 0-8] vs one line [0-10], p=0·029). In genomic analyses, ancestry-specific mutational landscapes were observed, but the prevalence of alterations in AR, the DNA damage response pathway, and other actionable genes were similar across ancestries. Similar genomic landscapes were observed in analyses that accounted for admixture-derived ancestry fractions. After undergoing CGP, men of African ancestry were less likely to receive a clinical study drug compared with men of European ancestry (12 [10%] of 118 vs 246 [26%] of 938, p=0·0005).

INTERPRETATION

Similar rates of gene alterations with therapy implications suggest that differences in actionable genes (including AR and DNA damage response pathway genes) might not be a main driver of disparities across ancestries in advanced prostate cancer. Later CGP utilisation and a lower rate of clinical trial enrolment observed in men of African ancestry could affect genomics, outcomes, and disparities.

FUNDING

American Society for Radiation Oncology, Department of Defense, Flatiron Health, Foundation Medicine, Prostate Cancer Foundation, and Sylvester Comprehensive Cancer Center.

Determinants of widespread metastases and of metastatic tropism in patients with prostate cancer: A genomic analysis of primary and metastatic tumors

INTRODUCTION

Emerging evidence suggests that metastasis is better described as a spectrum of disease rather than a binary state. A greater understanding of the genomic features that determine extent and location of metastatic spread may inform risk stratification and monitoring. Here, we identify genomic alterations from primary prostate carcinomas that are predictive of wide-spread metastatic potential.

METHODS

Genomic and clinical data from 1,312 patients with primary prostate carcinoma were extracted from the MSK-MET cohort through cBioPortal. Metastatic site counts and overall survival (OS) data were publicly available and used as the primary outcomes. Primary tumor samples were profiled using the MSK-IMPACT targeted sequencing platform. We focused on 58 genes frequently altered in prostate cancer. Cox proportional hazard analyses defined hazard ratios (HRs) and 95% confidence intervals (CIs) for overall mortality in patients with different metastatic outcomes.

RESULTS

Out of the 1,312 patients in our cohort, 939 (71%) developed metastases, of whom 113 (8.6%) had metastases to 5 or more distinct anatomical sites (defining wide-spread metastases, WSM). Bone was the most common site of metastasis (36%), and 80% of patients with liver metastases had 4 or more additional sites of metastasis. Among patients with metastasis, increasing number of metastatic sites was associated with increased risk of death (HR: 1.8, 95%CI: 1.63-1.99, P < 0.001). Alterations in the following genes were enriched in tumors from patients with WSM vs. others: TP53 (40% vs. 20%, P < 0.0001), FOXA1-amplification (8% vs. 3%, P = 0.02), AR-amplification (4.4% vs. 1%, P = 0.01), RB1-deletion (5.3% vs. 0.7%, P = 0.001), and BRCA2-deletion (4.4% vs. 0.7%, P = 0.01). Univariable survival analysis showed all these alterations were predictive of OS (P < 0.05). On multivariable analysis, only TP53 mutations, and FOXA1 and AR amplifications were independent prognostic factors. FOXA1 (n = 37) and AR (n = 13) amplifications were mutually exclusive and patients with these experienced very poor OS (HR: 3.57, 95%CI:2.26-5.6, P < 0.001].

CONCLUSIONS

We identified genomic alterations (TP53 mutations, FOXA1/AR amplification, RB1/BRCA2 deletion) from primary prostate carcinomas that are predictive of wide-spread metastases and poor outcome.

Management of Patients with Advanced Prostate Cancer. Part I: Intermediate-/High-risk and Locally Advanced Disease, Biochemical Relapse, and Side Effects of Hormonal Treatment: Report of the Advanced Prostate Cancer Consensus Conference 2022

BACKGROUND

Innovations in imaging and molecular characterisation and the evolution of new therapies have improved outcomes in advanced prostate cancer. Nonetheless, we continue to lack high-level evidence on a variety of clinical topics that greatly impact daily practice. To supplement evidence-based guidelines, the 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) surveyed experts about key dilemmas in clinical management.

OBJECTIVE

To present consensus voting results for select questions from APCCC 2022.

DESIGN, SETTING, AND PARTICIPANTS

Before the conference, a panel of 117 international prostate cancer experts used a modified Delphi process to develop 198 multiple-choice consensus questions on (1) intermediate- and high-risk and locally advanced prostate cancer, (2) biochemical recurrence after local treatment, (3) side effects from hormonal therapies, (4) metastatic hormone-sensitive prostate cancer, (5) nonmetastatic castration-resistant prostate cancer, (6) metastatic castration-resistant prostate cancer, and (7) oligometastatic and oligoprogressive prostate cancer. Before the conference, these questions were administered via a web-based survey to the 105 physician panel members ("panellists") who directly engage in prostate cancer treatment decision-making. Herein, we present results for the 82 questions on topics 1-3.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Consensus was defined as ≥75% agreement, with strong consensus defined as ≥90% agreement.

RESULTS AND LIMITATIONS

The voting results reveal varying degrees of consensus, as is discussed in this article and shown in the detailed results in the Supplementary material. The findings reflect the opinions of an international panel of experts and did not incorporate a formal literature review and meta-analysis.

CONCLUSIONS

These voting results by a panel of international experts in advanced prostate cancer can help physicians and patients navigate controversial areas of clinical management for which high-level evidence is scant or conflicting. The findings can also help funders and policymakers prioritise areas for future research. Diagnostic and treatment decisions should always be individualised based on patient and cancer characteristics (disease extent and location, treatment history, comorbidities, and patient preferences) and should incorporate current and emerging clinical evidence, therapeutic guidelines, and logistic and economic factors. Enrolment in clinical trials is always strongly encouraged. Importantly, APCCC 2022 once again identified important gaps (areas of nonconsensus) that merit evaluation in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with health care providers and patients worldwide. At each APCCC, a panel of physician experts vote in response to multiple-choice questions about their clinical opinions and approaches to managing advanced prostate cancer. This report presents voting results for the subset of questions pertaining to intermediate- and high-risk and locally advanced prostate cancer, biochemical relapse after definitive treatment, advanced (next-generation) imaging, and management of side effects caused by hormonal therapies. The results provide a practical guide to help clinicians and patients discuss treatment options as part of shared multidisciplinary decision-making. The findings may be especially useful when there is little or no high-level evidence to guide treatment decisions.

HIDRATE-PRO: A prospective pilot study evaluating a digital behavioral health intervention to improve bladder-filling compliance in patients with prostate cancer receiving radiation

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Background: Prostate cancer (PCa) patients undergoing radiation therapy (RT) need comfortably full bladders during RT to reduce toxicities. Awareness of this state is lacking, and poor compliance is common with standard of care written/verbal instructions, leading to wasted patient value (PV) and inefficient throughput (TE). Herein, we assessed the feasibility and acceptability of a digital behavioral intervention (DBI) to improve bladder filling compliance, methods for quantifying PV, IT, and behavioral biomarkers. Methods: We enrolled 18 non-metastatic PCa patients in a prospective, single-arm pilot study using a DBI. The DBI consists of a smart water bottle and companion app that tracks water consumption. Additionally, visual alerts (water bottle glow and phone notifications) remind the patient to empty his bladder and drink a personalized volume goal (VG) at a set time. The VG is based on simulation bladder volume and reminders are initially set 1.25 hours prior to scheduled RT. Patients were trained to adjust their VG and notification times to achieve comfortably full bladders. Primary endpoint was met if qualitative (QLC) and quantitative compliance (QNC) were both >80%. Other endpoints include acceptability assessed via Service User Technology Acceptability Questionnaire (SUTAQ), engagement (>80% of patients used the device > 50% of the time) and impact of DBI on PV and TE. For QLC, patients were asked if they prepared their bladders before daily RT. QNC was met if bladder volumes on daily CBCT were > 75% of the simulation’s volume. The SUTAQ was given pre- and post-DBI. PV and TE were measured by time spent in clinic and on the linear accelerator (linac), respectively. Biometric data was probed for insights on optimal drinking behaviors. Results: All endpoints were met. QLC was 100% on 375/398 (94.2%) of total treatments, while QNC was 88.9% on 341/398 (85.7%) total treatments. Patients were accepting of DBI with few privacy concerns (4.33/5.00), believe in benefits (4.00/5.00), high satisfaction (4.56/5.00) and high usability (4.24/5.00). Most patients, 15/18 (83.3%), used the DBI on >50% of treatments and met the engagement requirements. Patients with empty bladders (n=43) spent significantly more time (75.14 vs 50.59 minutes, p=0.007) in clinic than patients who came with full bladders (n=355). Similarly, these patients spent nearly twice as long on the linac (21.63 v 12.50 minutes, p<0.001). Shorter time spent drinking correlated with empty bladders (17.07 vs 27.85 min, p=0.027). Conclusions: This digital intervention trial showed high rates of bladder filling compliance and engagement. High patient-value and throughput efficiency was feasibly quantified by shortened clinic times and linac usage, respectively. Future studies are needed to evaluate clinical outcomes, patient experience and cost benefit. Clinical trial information: NCT04946214 .

Clinical and genomic factors associated with tumor mutational burden (TMB) in prostate cancer

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Background: TMB is an emerging biomarker to predict clinical benefit from immune checkpoint inhibitors (ICI). Although high TMB in prostate cancer is rare, and we sought to evaluate independent associations of TMB by clinical factors, prior treatment, and genomics. Methods: This study used the US-based nationwide de-identified Flatiron Health-Foundation Medicine prostate cancer clinico-genomic database. The de-identified data originated from approximately 280 US cancer clinics (~800 sites) between January 2011-March 2022. Multivariable linear regression model was used to assess independent prediction of TMB levels, which were log2+1 transformed to better normalize distribution. Data are expressed as (estimate, [95% CI], p-value). Results: The study included 2,748 tissue specimens: 51.7% were from the prostate, 10.3% from bone, and 14.6% from lymph nodes. Specimens from white patients comprised 61.2% of samples, with another 7.5% from Black, 1.1% from Asian, and 30% from other or unknown race patients. Of our cohort, 58.5%, 15.5%, and 26.0% were from patients who received 0, 1-24 months, and >24 months of androgen deprivation therapy (ADT), respectively. Also 19.7%, 1.8%, 11.4%, and 0.4% had any exposure to novel hormonal therapies (NHT), Radium-223, taxanes, and ICI, respectively. Higher TMB was independently associated with ADT use >24 months (0.16, [0.05-0.27], p=0.005) and Asian race (0.36, [0.03-0.69], p=0.034). Prior treatment with NHT, taxanes, or radium was not associated with higher TMB. Compared to prostate, bladder (0.22, [0.03-0.41], p=0.023), liver (0.27, [0.13-0.42], p<0.001), and other (0.29, [0.15-0.43], p<0.001) biopsy sites were associated with high TMB, but lymph node biopsy was not. MSI-high (2.30, [1.96-2.64], p<0.001), MSI-intermediate (0.51, [0.14-0.88], p=0.007), and MSI-unknown (0.84, [0.60-1.09], p<0.001) were associated with increased TMB. Individually altered genes associated with increased TMB included MLH1 (0.77, [0.31-1.24], p=0.001), MSH2 (1.09, [0.74-1.45], p<0.001), MSH3 (0.64, [0.018-1.11], p=0.006), MSH6 (0.94, [0.61-1.26], p<0.001), BRCA2 (0.56, [0.43-0.69], p<0.001), CDK12 (0.38, [0.24-0.53], p<0.001), FANCA (0.42, [0.07-0.77], p=0.02), MRE11 (0.87, [0.11-1.62], p=0.025), and PALB2 (0.83, [0.48-1.18], p<0.001). No individual gene was independently associated with lower TMB. Conclusions: TMB associates with MSI status and MMR genes. However, aside from associating with long term ADT use, TMB does not have strong association with prior systemic treatment. Certain biopsy specimen sites including bladder and liver have increased TMB but overall, the association is relatively weak in comparison to MMR genes and MSI status. This study allows better understanding of how prior treatments, clinical and genomic factors affect TMB status, which may add value to MSI status in predicting treatment response in advanced prostate cancer.

Distinct Profiles of DNA Repair Activity Define Favorable-risk Prostate Cancer Subtypes With Divergent Outcome

INTRODUCTION

Understanding if divergent molecular profiles of DNA damage and repair (DDR) pathway activity, a biomarker of disease progression, exist in prostate tumors with favorable-risk features is an unmet need, which this study aim to unearth.

MATERIALS AND METHODS

This was a multicenter registry genome-wide expression profiling study of prospectively collected radical prostatectomy (RP) tumor samples from 2014 to 2016. DDR activity was calculated from average expression of 372 DDR genes. Consensus hierarchical clustering was used to arrive at a robust clustering solution based on DDR gene expression patterns. Genome-wide differential expression between clusters was performed, and outcomes were evaluated across expression patterns.

RESULTS

Of 5239 patients from the prospective registry, 376 had favorable-risk disease (Grade group [GG] 1 to 2, PSA prior to RP <10ng/ml, pT2 or less). DDR activity score was correlated with prognostic genomic signatures that predict for metastatic risk (r = 0.37, P < 2e^-16) and high grade groups (P < .001). High DDR activity (top-quartile) was observed in 28% of patients with favorable-risk disease. In favorable-risk disease, 3 distinct clusters with varied DDR activity emerged with consensus clustering. Cluster I (compared with cluster II-III and GG3-GG5 disease) had the highest expression of all DDR sub-pathways, MYC, PAPR1, AR, and AR activity (P < .001 for all). Furthermore, cluster I was associated with poorer metastasis-free survival (MFS) and Overall survival (OS) compared with other clusters (MFS; HR: 2.43, 95%CI, [1.22-4.83], P = .01; OS; HR: 2.77, 95%CI, [1.18-6.5], P = .01).

CONCLUSIONS

Cluster I is a novel subgroup of favorable-risk disease with high DDR activity, AR activity, PARP1 and chr8q/MYC expression, and poorer MFS and OS.

Chromosome 8q arm overexpression is associated with worse prostate cancer prognosis

OBJECTIVE

Chromosome 8q arm (chr8q) is the most amplified chromosomal segment in advanced metastatic castration-resistant prostate cancer after chXq12. These regions harbor important oncogenes driving prostate cancer progression, including MYC that plays a role in various hallmarks of cancer, including cell cycle progression and immune surveillance. Herein we characterize the co-expression patterns of chr8q genes and their clinical utility in more than 7,000 radical prostatectomy samples.

MATERIALS AND METHODS

Copy Number alterations of 336 genes on chr8q21 to chr8q24 were extracted from 2 primary prostate cancer cohorts (TCGA, n = 492; MSK-primary, n = 856) and 3 metastatic prostate cancer cohorts (MSK-met, N = 432; MSK-mCSPC, N = 424; SU2CPNAS, n = 444) from cBioPortal. Expression data for the 336 genes was extracted from 6,135 radical prostatectomy samples from Decipher GRID registry. For survival analysis, patients were grouped into top 10% and top 25% by band expression and were compared with the remaining cohort. Hazard ratios were calculated using Cox proportional hazards models.

RESULTS

Genes on chr8q were highly co-amplified and co-expressed. Copy number alterations and overexpression of chr8q genes in primary disease were associated with higher Gleason scores, increased risk of metastases, and increased prostate cancer specific mortality. Additionally, our data demonstrated high expression of MYC alone was not associated with differences in metastases free survival while high expression of other chr8q bands was associated with decreased metastases free survival. By combining chr8q data with an established genomic classifier like Decipher, we were able to develop a new model that was better at predicting metastases than Decipher alone.

CONCLUSIONS

Our findings highlight the clinical utility of chr8q data, which can be used to improve prognostication and risk prediction in localized prostate cancer.

Shorter Radiation Regimens and Treatment Noncompletion Among Patients With Breast and Prostate Cancer in the United States: An Analysis of Racial Disparities in Access and Quality

PURPOSE

Compared with conventional external-beam radiation therapy (cEBRT) for patients with breast cancer (BC) and prostate cancer (PC), shorter radiation regimens may be associated with lower treatment noncompletion rates. We assess disparities in receipt of shorter radiation regimens and treatment noncompletion for BC and PC.

PATIENTS AND METHODS

The 2004-2017 National Cancer Database was queried for adjuvant cEBRT or hypofractionated EBRT (hEBRT) for nonmetastatic BC; and definitive cEBRT, moderate hypofractionation (mEBRT), or stereotactic body radiotherapy (SBRT) for localized PC. Multivariable logistic regression identified factors associated with treatment noncompletion and receipt of shorter regimens.

FINDINGS

We identified 170,386 men with PC (median age [interquartile range], 70 [64-75] years; Black, 17.5%; White, 82.5%) and 306,846 women with BC (61 [52-69] years; Black, 12.3%; White, 87.7%). Among patients who received cEBRT for PC, Black men had higher treatment noncompletion rates compared with White (14.1% v 13.0%; odds ratio [95% CI] 1.07 [1.03 to 1.12]; P < .001). In contrast, treatment noncompletion was not disparate with SBRT (Black 1.6% v White 1.3%; 1.20 [0.72 to 2.00], P = .49) or mEBRT (Black 9.0% v White 7.1%; 1.05 [0.72 to 1.54], P = .79). From 2004 to 2017, SBRT (0.07% to 11.8%; 1.32 [1.31 to 1.33]) and mEBRT (0.35% to 9.1%; 1.27 [1.25 to 1.28]) increased (both P < .001); however, Black men were consistently less likely to receive SBRT (7.4% v White, 8.3%; 0.84 [0.79 to 0.89], P < .001). Among women with BC, there were no racial differences in treatment noncompletion; however, hEBRT was associated with lower treatment noncompletion rates (1.0% v cEBRT 2.3%; 0.39 [0.35 to 0.44], P < .001). Although hEBRT for BC increased (0.8% to 35.6%) between 2004 and 2017, Black women were less likely to receive hEBRT (10.4% v 15.3%; 0.78 [0.75 to 0.81], P < .001).

INTERPRETATION

Black patients were consistently less likely to receive hypofractionated radiation for PC or BC, despite evidence suggesting that shorter regimens may lower rates of treatment noncompletion with similar oncologic outcomes.

Best Current Practice and Research Priorities in Active Surveillance for Prostate Cancer-A Report of a Movember International Consensus Meeting

BACKGROUND

Active surveillance (AS) is recommended for low-risk and some intermediate-risk prostate cancer. Uptake and practice of AS vary significantly across different settings, as does the experience of surveillance-from which tests are offered, and to the levels of psychological support.

OBJECTIVE

To explore the current best practice and determine the most important research priorities in AS for prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

A formal consensus process was followed, with an international expert panel of purposively sampled participants across a range of health care professionals and researchers, and those with lived experience of prostate cancer. Statements regarding the practice of AS and potential research priorities spanning the patient journey from surveillance to initiating treatment were developed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Panel members scored each statement on a Likert scale. The group median score and measure of consensus were presented to participants prior to discussion and rescoring at panel meetings. Current best practice and future research priorities were identified, agreed upon, and finally ranked by panel members.

RESULTS AND LIMITATIONS

There was consensus agreement that best practice includes the use of high-quality magnetic resonance imaging (MRI), which allows digital rectal examination (DRE) to be omitted, that repeat standard biopsy can be omitted when MRI and prostate-specific antigen (PSA) kinetics are stable, and that changes in PSA or DRE should prompt MRI ± biopsy rather than immediate active treatment. The highest ranked research priority was a dynamic, risk-adjusted AS approach, reducing testing for those at the least risk of progression. Improving the tests used in surveillance, ensuring equity of access and experience across different patients and settings, and improving information and communication between and within clinicians and patients were also high priorities. Limitations include the use of a limited number of panel members for practical reasons.

CONCLUSIONS

The current best practice in AS includes the use of high-quality MRI to avoid DRE and as the first assessment for changes in PSA, with omission of repeat standard biopsy when PSA and MRI are stable. Development of a robust, dynamic, risk-adapted approach to surveillance is the highest research priority in AS for prostate cancer.

PATIENT SUMMARY

A diverse group of experts in active surveillance, including a broad range of health care professionals and researchers and those with lived experience of prostate cancer, agreed that best practice includes the use of high-quality magnetic resonance imaging, which can allow digital rectal examination and some biopsies to be omitted. The highest research priority in active surveillance research was identified as the development of a dynamic, risk-adjusted approach.

Disparities in access to cancer diagnostics in ASEAN member countries

Diagnostics, including laboratory tests, medical and nuclear imaging, and molecular testing, are essential in the diagnosis and management of cancer to optimize clinical outcomes. With the continuous rise in cancer mortality and morbidity in the Association of Southeast Asian Nations (ASEAN), there exists a critical need to evaluate the accessibility of cancer diagnostics in the region so as to direct multifaceted interventions that will address regional inequities and inadequacies in cancer care. This paper identifies existing gaps in service delivery, health workforce, health information systems, leadership and governance, and financing and how these contribute to disparities in access to cancer diagnostics in ASEAN member countries. Intersectoral health policies that will strengthen coordinated laboratory services, upscale infrastructure development, encourage health workforce production, and enable proper appropriation of funding are necessary to effectively reduce the regional cancer burden.

Evaluation of Social Determinants of Health and Prostate Cancer Outcomes Among Black and White Patients: A Systematic Review and Meta-analysis

IMPORTANCE

As the field of medicine strives for equity in care, research showing the association of social determinants of health (SDOH) with poorer health care outcomes is needed to better inform quality improvement strategies.

OBJECTIVE

To evaluate the association of SDOH with prostate cancer-specific mortality (PCSM) and overall survival (OS) among Black and White patients with prostate cancer.

DATA SOURCES

A MEDLINE search was performed of prostate cancer comparative effectiveness research from January 1, 1960, to June 5, 2020.

STUDY SELECTION

Two authors independently selected studies conducted among patients within the United States and performed comparative outcome analysis between Black and White patients. Studies were required to report time-to-event outcomes. A total of 251 studies were identified for review.

DATA EXTRACTION AND SYNTHESIS

Three authors independently screened and extracted data. End point meta-analyses were performed using both fixed-effects and random-effects models. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed, and 2 authors independently reviewed all steps. All conflicts were resolved by consensus.

MAIN OUTCOMES AND MEASURES

The primary outcome was PCSM, and the secondary outcome was OS. With the US Department of Health and Human Services Healthy People 2030 initiative, an SDOH scoring system was incorporated to evaluate the association of SDOH with the predefined end points. The covariables included in the scoring system were age, comorbidities, insurance status, income status, extent of disease, geography, standardized treatment, and equitable and harmonized insurance benefits. The scoring system was discretized into 3 categories: high (≥10 points), intermediate (5-9 points), and low (<5 points).

RESULTS

The 47 studies identified comprised 1 019 908 patients (176 028 Black men and 843 880 White men; median age, 66.4 years [IQR, 64.8-69.0 years]). The median follow-up was 66.0 months (IQR, 41.5-91.4 months). Pooled estimates found no statistically significant difference in PCSM for Black patients compared with White patients (hazard ratio [HR], 1.08 [95% CI, 0.99-1.19]; P = .08); results were similar for OS (HR, 1.01 [95% CI, 0.95-1.07]; P = .68). There was a significant race-SDOH interaction for both PCSM (regression coefficient, -0.041 [95% CI, -0.059 to 0.023]; P < .001) and OS (meta-regression coefficient, -0.017 [95% CI, -0.033 to -0.002]; P = .03). In studies with minimal accounting for SDOH (<5-point score), Black patients had significantly higher PCSM compared with White patients (HR, 1.29; 95% CI, 1.17-1.41; P < .001). In studies with greater accounting for SDOH variables (≥10-point score), PCSM was significantly lower among Black patients compared with White patients (HR, 0.86; 95% CI, 0.77-0.96; P = .02).

CONCLUSIONS AND RELEVANCE

The findings of this meta-analysis suggest that there is a significant interaction between race and SDOH with respect to PCSM and OS among men with prostate cancer. Incorporating SDOH variables into data collection and analyses are vital to developing strategies for achieving equity.

Disparities in Primary Breast Cancer Stage at Presentation Among Hispanic Subgroups

BACKGROUND

Although the United States (US) Hispanic population consists of diverse communities, prior breast cancer studies often analyze this group in aggregate. Our aim was to identify differences in breast cancer stage at presentation in the US population, with a particular focus on Hispanic subgroups.

METHODS

Data from the National Cancer Database (NCDB) from 2004 to 2017 were used to select women with primary breast cancer; individuals were disaggregated by racial and ethnic subgroup and Hispanic country of origin. Ordinal logistic regression was used to create adjusted odds ratios (aORs) with 95% confidence intervals (CIs), with higher odds representing presentation at later-stage breast cancer. Subgroup analysis was conducted based on tumor receptor status.

RESULTS

Overall, among 2,282,691 women (5.2% Hispanic), Hispanic women were more likely to live in low-income and low-educational attainment neighborhoods, and were also more likely to be uninsured. Hispanic women were also more likely to present at later-stage primary breast cancer when compared with non-Hispanic White women (aOR 1.19, 95% CI 1.18-1.21; p < 0.01). Stage disparities were demonstrated when populations were disaggregated by country of origin, particularly for Mexican women (aOR 1.55, 95% CI 1.51-1.60; p < 0.01). Disparities worsened among both racial and country of origin subgroups in women with triple-negative disease.

CONCLUSION

Later breast cancer stage at presentation was observed among Hispanic populations when disaggregated by racial subgroup and country of origin. Socioeconomic disparities, as well as uncaptured disparities in access and/or differential care, may drive these observed differences. Future studies with disaggregated data are needed to characterize outcomes in Hispanic communities and develop targeted interventions.

Shared burden: the association between cancer diagnosis, financial toxicity, and healthcare cost-related coping mechanisms by family members of non-elderly patients in the USA

PURPOSE

There has been little research on the healthcare cost-related coping mechanisms of families of patients with cancer. Therefore, we assessed the association between a cancer diagnosis and the healthcare cost-related coping mechanisms of participant family members through their decision to forego or delay seeking medical care, one of the manifestations of financial toxicity.

METHODS

Using data from the National Health Interview Survey (NHIS) between 2000 and 2018, sample weight-adjusted prevalence was calculated and multivariable logistic regressions defined adjusted odds ratios (aORs) for participant family members who needed but did not get medical care or who delayed seeking medical care due to cost in the past 12 months, adjusting for relevant sociodemographic covariates, including participant history of cancer (yes vs. no) and participant age (18-45 vs. 46-64 years old). The analysis of family members foregoing or delaying medical care was repeated using a cancer diagnosis * age interaction term.

RESULTS

Participants with cancer were more likely than those without a history of cancer to report family members delaying (19.63% vs. 16.31%, P < 0.001) or foregoing (14.53% vs. 12.35%, P = 0.001) medical care. Participants with cancer in the 18 to 45 years old age range were more likely to report family members delaying (p_interaction = 0.028) or foregoing (p_interaction < 0.001) medical care. Other factors associated with cost-related coping mechanisms undertaken by the participants' family members included female sex, non-married status, poorer health status, lack of health insurance coverage, and lower household income.

CONCLUSION

A cancer diagnosis may be associated with familial healthcare cost-related coping mechanisms, one of the manifestations of financial toxicity. This is seen through delayed/omitted medical care of family members of people with a history of cancer, an association that may be stronger among young adult cancer survivors. These findings underscore the need to further explore how financial toxicity associated with a cancer diagnosis can affect patients' family members and to design interventions to mitigate healthcare cost-related coping mechanisms.

Racial disparities in Black men with prostate cancer: A literature review

Black men are disproportionately affected by prostate cancer (PCa), with earlier presentation, more aggressive disease, and higher mortality rates versus White men. Furthermore, Black men have less access to PCa treatment and experience longer delays between diagnosis and treatment. In this review, the authors discuss the factors contributing to racial disparities and present solutions to improve access to care and increase clinical trial participation among Black men with PCa. Racial disparities observed among Black men with PCa are multifaceted, evolving from institutional racism. Cultural factors include generalized mistrust of the health care system, poor physician-patient communication, lack of information on PCa and treatment options, fear of PCa diagnosis, and perceived societal stigma of the disease. In the United States, geographic trends in racial disparities have been observed. Economic factors, e.g., cost of care, recovery time, and cancer debt, play an important role in racial disparities observed in PCa treatment and outcomes. Racial diversity is often lacking in genomic and precision medicine studies. Black men are largely underrepresented in key phase 3 PCa trials and may be less willing to enroll in clinical trials due to lack of awareness, lack of diversity in clinical trial research teams, and bias of health care providers to recommend clinical research. The authors propose solutions to address these factors that include educating clinicians and institutions on the barriers Black men experience, increasing the diversity of health care providers and clinical research teams, and empowering Black men to be involved in their treatment, which are keys to creating equity for Black men with PCa. LAY SUMMARY: Prostate cancer negatively affects Black men more than men of other races. The history of segregation and mistreatment in the health care system may contribute to mistrust among Black men. Outcomes are worse for Black men because they are less likely to be screened or to receive treatment for prostate cancer. Black men also are unlikely to participate in clinical research, making it difficult for investigators to understand how Black men are affected by prostate cancer. Suggestions for addressing these differences include teaching physicians and nurses about the issues Black men experience getting treatment and improving how Black men get information on prostate cancer.

Substantial Gleason reclassification in Black men with national comprehensive cancer network low-risk prostate cancer - A propensity score analysis

BACKGROUND

Emerging evidence suggests that a subset of Black men with National Comprehensive Cancer Network (NCCN) low-risk prostate cancer (PCa) may harbor high volume and genomically aggressive disease. However, limited, and ambiguous research exist to evaluate the risk of extreme Gleason reclassification in Black men with low-risk PCa.

METHODS

This retrospective cohort study included 45,674 low-risk PCa patients who underwent prostatectomy and were not on active surveillance, from National Cancer Database (NCDB). A propensity score matched-pair design was employed, and the final cohort was limited to 1:1 matched 12,340 patients. Gleason score reclassification was used as primary endpoint. As such, any migration to pathologic Gleason score ≥7(3 + 4) was identified as overall, whereas migration to ≥7(4 + 3) was defined as extreme reclassification. A conditional Poisson regression model was used to estimate the risk of reclassification. Whereas spline model was used to estimate the impact of increasing time to treatment as a non-linear function on Gleason reclassification between race group.

RESULTS

Upon matching there were no differences in the baseline characteristics between race groups. In a matched cohort, higher proportion of low-risk Black men (6.6%) reported extreme reclassification to pathologic Gleason score than White men (5.0%), p < 0.001. In a conditional Poisson regression model adjusted for time to treatment, the risk of overall (RR = 1.09, 95% CI, 1.05-1.13, p < 0.001) and extreme (RR = 1.30, 95% CI, 1.12-1.50, p = 0.004) reclassification was significantly higher in Black men as compared to their White counterpart. In spline model, the probability of Gleason reclassification in Black men was elevated with increasing time to treatment, especially after 180 days (53% vs. 43% between Black and White men).

CONCLUSION

Risk of Gleason score reclassification is disparately elevated in Black men with low-risk PCa. Furthermore, time to treatment can non-linearly impact Gleason reclassification in Black men.

Para-Aortic Radiation Therapy for Oligorecurrent Prostate Cancer

PURPOSE

Oligorecurrent prostate cancer limited to the pelvic lymph nodes (LNs) can be treated with whole pelvis radiotherapy. Radiotherapy may also be beneficial for oligorecurrent prostate cancer in the para-aortic (PA) LNs.

METHODS

We identified a sequential cohort of patients with oligorecurrent prostate cancer to the PA LNs (≤5) treated with elective, conventionally fractionated PA radiotherapy (PA-RT) plus simultaneous integrated boost (SIB) to LN+ disease at our institution from 2015 to 2021. The primary endpoint was progression-free survival (PFS) at 2 years using Kaplan-Meier estimation. PFS was defined as the time from PA-RT to the first event: biochemical failure (PSA 50% above post-treatment nadir and at least 4 ng/mL), escalation of therapy, radiological progression, or death. Secondary endpoints included 2-year biochemical failure-free survival (BFFS), 2-year overall survival (OS) and treatment-related toxicity.

RESULTS

Thirty-four patients were included (median age 66 years), and 82.4% were status post-prostatectomy. The median time from diagnosis to PA-RT was 5.7 years. The median PSA at PA-RT was 3.15 ng/mL (IQR 1.30-5.90). All patients were treated to the PA region with 45-50 Gy in 25 daily fractions. LN+ disease received a SIB to a median dose of 62.5 Gy (range 60-65 Gy). Most received photon-based RT, while 21.1% were treated with proton therapy. Nearly all (97.1%) patients had androgen deprivation therapy (ADT) and 52.9% abiraterone. The median follow-up time from PA-RT was 21.5 months. PFS at 2-years was 83.4% (95% CI: 68.6-100%). Two-year BFFS was 90.4% and OS 100%. There were no grade 3 or higher acute toxicities. There were 10 (29.4%) grade 2 acute toxicities. There were two (5.9%) grade 3 chronic toxicities and 4 (11.8%) chronic grade 2 toxicities.

CONCLUSION

PA-RT for oligorecurrent prostate cancer has low toxicity with very encouraging early disease control. These preliminary results require validation in prospective studies.

Financial toxicity in Hispanic cancer survivors: A nationally representative pancancer analysis

6528

Background: A cancer diagnosis can pose a significant financial burden to patients and their families, both during and after treatment. Financial toxicity has long-term consequences, with cancer being the most commonly cited reason for medical cost-associated bankruptcy in the United States. We used nationally representative survey data to assess financial toxicity in cancer survivors, with a focus on Hispanic patients given known disparities in socioeconomic and cancer outcomes. Methods: 2013-2018 data from the National Health Interview Survey (NHIS) was used to select individuals aged 18 years old and older who reported any previous diagnosis of cancer. Financial toxicity was defined as unmet healthcare need, health care unaffordability, and/or general financial stress. Individuals were disaggregated by race/ethnicity, and patients who self-identified as Hispanic were further classified by country of origin. Survey-adjusted percentages characterize the cohort. Multivariable logistic regression generated adjusted odds ratios (aORs) with 95% CI for each category of financial toxicity, with non-Hispanic White (NHW) used as reference. Results: Hispanic patients in aggregate had the highest prevalence of all 3 categories of financial toxicity when compared to other racial/ethnicity groups (35% unmet healthcare need, 61% healthcare unaffordability, 61% financial stress). Mexican (aOR: 2.53 95%CI: 1.82–3.52), Cuban/Cuban-American (aOR: 1.97 95%CI: 1.17–3.34), and patients of Central/South American heritage (aOR: 2.61 95%CI: 1.67–4.10) were more likely to have healthcare unaffordability. Unmet healthcare needs were higher in Mexican patients (aOR: 1.43 95%CI: 1.03-1.99) and patients of Cuban descent (aOR: 1.96 95%CI: 1.07-3.58). Financial stress was highest among patients of Central/South American heritage (aOR: 4.20 95%CI: 2.50-7.05) and Mexican patients (aOR: 1.84 95%CI: 1.27-2.66). Mediator analyses further revealed that disparities persisted even after adjusting for socioeconomic status in Mexican patients (healthcare unaffordability - aOR: 1.65 95%CI: 1.14-2.40) and patients of Central/South American heritage (healthcare unaffordability – aOR: 1.99 95%CI: 1.23-3.21; general financial stress – aOR: 2.97 95%CI: 1.71 – 5.17). Conclusions: Our study highlights significant disparities in the financial impact of cancer treatments on Hispanic patients. Disaggregation by Hispanic country of origin illustrates differences within the Hispanic and Hispanic-American population and reveals specific groups that may be at particular risk of financial harm. Targeted interventions to improve health care access and affordability are needed to increase equity and improve outcomes.

Disparities in delayed diagnosis, access to treatment, and treatment delays among Hispanic men with metastatic prostate cancer

6550

Background: Reporting racial/ethnic disparities in aggregate for Hispanics could obscure differences between subgroups given heterogeneity in social determinants of health. We sought to identify differences in delayed diagnosis, treatment status, and time to treatment among Hispanic subpopulations with metastatic prostate cancer. Methods: 2004-2017 data from the National Cancer Database (NCDB) was used to identify patients with prostate adenocarcinoma; patients were disaggregated by racial subgroup and Hispanic country-of-origin. Ordinal logistic regression defined adjusted odds ratios (aORs) with 95% CI of 1) presenting with Stage IV cancer, 2) receiving treatment, and 3) receiving delayed treatment (defined as treatment after 90 days). Sensitivity analysis was conducted for delayed treatment after 180 days. Results: Among 1,305,785 patients, Hispanic men had greater odds of presenting with stage IV prostate cancer compared with non-Hispanic White (NHW) men (aOR = 1.54 95% CI 1.50-1.58, p < 0.001). All Hispanic racial subgroups were more likely to present with stage IV cancer with highest odds observed in Hispanic Black men (aOR 1.68 95% CI 1.46-1.93, p < 0.001). Disparities were also observed in all country of origin subgroups, particularly for men of Mexican heritage (aOR 1.99 95% CI 1.86-2.12, p < 0.001). Among men with metastatic disease, Hispanic men were less likely to receive treatment than NHW men (aOR 0.60 95% CI 0.53-0.67, p < 0.001). Hispanic White patients were less likely to receive treatment compared with NHW men (Hispanic White aOR 0.58 95% CI 0.52-0.66, p < 0.001). Upon disaggregation by country of origin, disparities persisted, particularly for men of Dominican heritage (aOR 0.52 95%CI 0.28-0.98 p = 0.044). Hispanic men were more likely to experience treatment delays when compared to NHW men (aOR 1.38 95%CI 1.26-1.52 p < 0.001). All Hispanic racial subgroups experienced greater treatment delays, particularly Hispanic Black men (aOR 1.83 95%CI 1.22-2.75 p = 0.002). Men of Central or South American heritage had the greatest odds of treatment delays (aOR 1.48 95%CI 1.07-2.04 p = 0.018). Sensitivity analysis indicated consistent findings among Hispanic patients overall, Hispanic White patients, and patients of Mexican and Puerto Rican heritage. Conclusions: We found notable differences in stage IV cancer at presentation, treatment for metastatic disease, and delays in treatment when outcomes were stratified by racial subgroup and Hispanic country of origin. Future studies in Hispanic populations with disaggregated data are needed to characterize outcomes, study mediators of the observed variations, and develop targeted interventions.

Association of race with receipt of definitive therapy for high risk prostate cancer in older men

OBJECTIVES

Black men are more likely to die of prostate cancer (PCa) than White men. Whether this difference is driven by biological versus sociodemographic and access to care differences is actively investigated. However, studies that have highlighted racial disparities in PCa outcomes have been poorly represented by elderly men, a notoriously undertreated group. Herein, we evaluated use of curative treatment between Black and White elderly men with aggressive PCa in a large US database.

METHODS

Men ≥80 years diagnosed with National Comprehensive Cancer Network-defined high risk PCa between 2004 and 2016 were analyzed from the National Cancer Database. Multivariable logistic regression was used to model the effect of race and sociodemographic factors on receipt of definitive therapy (surgery or radiation +/- androgen deprivation therapy [ADT]) versus non-definitive therapy (ADT alone or observation) in inverse probability weighted groups matched for stage, prostate-specific antigen, and Gleason score.

RESULTS

Between 2004 and 2016, utilization of definitive therapy with either surgery or radiation therapy increased in both White and Black men in the United States. However, we found that Black men compared with White men were significantly less likely to receive definitive therapy (OR 0.71, 95% CI 0.64-0.79, p < .001). Using multivariable modeling, effect size diminished after adjusting for sociodemographic variables. Notably, there is evidence of the racial disparity narrowing over time.

CONCLUSIONS

These findings highlight striking but improving racial disparities in elderly men with high risk PCa in the US, an overall undertreated population.

Racial Differences in Genomic Profiles of Breast Cancer

This genetic association study examines the tumor genomic profiles by race in a large, diverse patient cohort using next-generation sequencing (NGS) data in the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange.

Prostate Cancer Disparities in Risk Group at Presentation and Access to Treatment for Asian Americans, Native Hawaiians, and Pacific Islanders: A Study With Disaggregated Ethnic Groups

PURPOSE

We identified (1) differences in localized prostate cancer (PCa) risk group at presentation and (2) disparities in access to initial treatment for Asian American, Native Hawaiian, and Pacific Islander (AANHPI) men with PCa after controlling for sociodemographic factors.

METHODS

We assessed all patients in the National Cancer Database with localized PCa with low-, intermediate-, and high-risk disease who identified as Thai, White, Asian Indian, Chinese, Vietnamese, Korean, Japanese, Filipino, Hawaiian, Pacific Islander, Laotian, Pakistani, Kampuchean, and Hmong. Multivariable logistic regression defined adjusted odds ratios (AORs) with 95% CI of (1) presenting at progressively higher risk group and (2) receiving treatment or active surveillance with intermediate- or high-risk disease, adjusting for sociodemographic and clinical factors.

RESULTS

Among 980,889 men (median age 66 years), all AANHPI subgroups with the exception of Thai (AOR = 0.84 [95% CI, 0.58 to 1.21], P > .05), Asian Indian (AOR = 1.12 [95% CI, 1.00 to 1.25], P > .05), and Pakistani (AOR = 1.34 [95% CI, 0.98 to 1.83], P > .05) men had greater odds of presenting at a progressively higher PCa risk group compared with White patients (Chinese AOR = 1.18 [95% CI, 1.11 to 1.25], P < .001; Japanese AOR = 1.36 [95% CI, 1.26 to 1.47], P < .001; Filipino AOR = 1.37 [95% CI, 1.29 to 1.46], P < .001; Korean AOR = 1.32 [95% CI, 1.18 to 1.48], P < .001; Vietnamese AOR = 1.20 [95% CI, 1.07 to 1.35], P = .002; Laotian AOR = 1.60 [95% CI, 1.08 to 2.36], P = .018; Hmong AOR = 4.07 [95% CI, 1.54 to 10.81], P = .005; Kampuchean AOR = 1.55 [95% CI, 1.03 to 2.34], P = .036; Asian Indian or Pakistani AOR = 1.15 [95% CI, 1.07 to 1.24], P < .001; Native Hawaiians AOR = 1.58 [95% CI, 1.38 to 1.80], P < .001; and Pacific Islanders AOR = 1.58 [95% CI, 1.37 to 1.82], P < .001). Additionally, Japanese Americans (AOR = 1.46 [95% CI, 1.09 to 1.97], P = .013) were more likely to receive treatment compared with White patients.

CONCLUSION

Our findings suggest that there are differences in PCa risk group at presentation by race or ethnicity among Asian American, Native Hawaiian, and Pacific Islander subgroups and that there exist disparities in treatment patterns. Although AANHPI are often studied as a homogenous group, heterogeneity upon subgroup disaggregation underscores the importance of further study to assess and address barriers to PCa care.

Comparison of Response to Definitive Radiotherapy for Localized Prostate Cancer in Black and White Men: A Meta-analysis

IMPORTANCE

Black men have a 2-fold increased risk of dying from prostate cancer compared with White men. However, race-specific differences in response to initial treatment remain unknown.

OBJECTIVE

To compare overall and treatment-specific outcomes of Black and White men with localized prostate cancer receiving definitive radiotherapy (RT).

DATA SOURCES

A systematic search was performed of relevant published randomized clinical trials conducted by the NRG Oncology/Radiation Therapy Oncology Group between January 1, 1990, and December 31, 2010. This meta-analysis was performed from July 1, 2019, to July 1, 2021.

STUDY SELECTION

Randomized clinical trials of definitive RT for patients with localized prostate cancer comprising a substantial number of Black men (self-identified race) enrolled that reported on treatment-specific and overall outcomes.

DATA EXTRACTION AND SYNTHESIS

Individual patient data were obtained from 7 NRG Oncology/Radiation Therapy Oncology Group randomized clinical trials evaluating definitive RT with or without short- or long-term androgen deprivation therapy. Unadjusted Fine-Gray competing risk models, with death as a competing risk, were developed to evaluate the cumulative incidences of end points. Cox proportional hazards models were used to evaluate differences in all-cause mortality and the composite outcome of distant metastasis (DM) or death. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed.

MAIN OUTCOMES AND MEASURES

Subdistribution hazard ratios (sHRs) of biochemical recurrence (BCR), DM, and prostate cancer-specific mortality (PCSM).

RESULTS

A total of 8814 patients (1630 [18.5%] Black and 7184 [81.5%] White) were included; mean (SD) age was 69.1 (6.8) years. Median follow-up was 10.6 (IQR, 8.0-17.8) years for surviving patients. At enrollment, Black men were more likely to have high-risk disease features. However, even without adjustment, Black men were less likely to experience BCR (sHR, 0.88; 95% CI, 0.58-0.91), DM (sHR, 0.72; 95% CI, 0.58-0.91), or PCSM (sHR, 0.72; 95% CI, 0.54-0.97). No significant differences in all-cause mortality were identified (HR, 0.99; 95% CI, 0.92-1.07). Upon adjustment, Black race remained significantly associated with improved BCR (adjusted sHR, 0.79; 95% CI, 0.72-0.88; P < .001), DM (adjusted sHR, 0.69; 95% CI, 0.55-0.87; P = .002), and PCSM (adjusted sHR, 0.68; 95% CI, 0.50-0.93; P = .01).

CONCLUSIONS AND RELEVANCE

The findings of this meta-analysis suggest that Black men enrolled in randomized clinical trials present with more aggressive disease but have better BCR, DM, and PCSM with definitive RT compared with White men, suggesting that other determinants of outcome, such as access to care, are important factors of achieving racial equity.