Health disparities in metastatic hormone-sensitive prostate cancer (mHSPC) presentations and outcomes among Hispanic Americans (HA) versus non-Hispanic Whites (NHW).

Abstract

31 Background: Multiple retrospective studies conducted have demonstrated disparities in access to care and treatment rates for prostate cancer between HA and NHW. We sought to understand the differences in prostate cancer presenting characteristics, prognosis, and outcomes between the two ethnic groups who presented to the University of Arizona Cancer Center (UACC), which serves a large Hispanic community. Methods: A retrospective analysis of mHSPC adenocarcinoma patients who presented to UACC from 2016 to 2022 was conducted. Patients must have had genetic testing to be included. Patients with no metastasis and incomplete data were excluded. Continuous data were analyzed using t-tests or Wilcoxon Rank sum tests depending on whether they were normally distributed. Categorical variables were analyzed using X2 Tests or Fisher's exact tests. Time to Event data was analyzed using Kaplan-Meier Methods. Results: 83 patients were included with 38.5% HA. No difference was observed between the ethnic groups by median age at presentation (66 years), race (90% white), obesity (40% BMI>30), personal cancer history (10%), or family history of cancer (48%). HA were more likely to have a smoking (69%) and alcohol (63%) history compared to NHW (54% and 39%, respectively; p= 0.04). On presentation, 56% of HA were ECOG 0 compared to 22% of NHW (p=0.001). At the time of diagnosis, HA had median PSA levels of 111.5 ng/ml compared to 52.6 ng/ml in NHW (p=0.12). Gleason Grade Group ≥4 in 73% HA vs 79% in NHW (p=0.61). 41% of HA presented with T4 disease compared to 14% of NHW (p=0.01). 69% of HA presented with N1 disease vs 61% of NHW (p=0.85). 41% of HA presented with visceral metastasis, M1c, compared to 16% of NHW (p=0.04). The median time to first-line (1L) treatment was 1 month in HA compared to 3 months for NHW (p<0.01). 84% of all patients had 1L combination therapy. Abiraterone plus ADT was 1L in 47% of HA compared to 20% of NHW (p=0.06). ADT plus androgen receptor blocker was 1L in 41% of NHW compared to 28% of HA (p=0.06). Median PSA response 3 months after starting treatment was 0.8 ng/ml in HA vs 3.96 ng/ml NHW (p=0.05). The median time to 2L was 20 months for HA vs 11 months in NHW (p=0.05). Conclusions: HA in our study presented with higher PSA, more locally advanced disease, and increased rates of visceral metastases, necessitating a shorter time interval to 1L therapy. HA demonstrated a more favorable response to 1L treatment, noted by lower PSA at 3 months and time to the next line of treatment. Overall survival was not calculated due to the small sample size with only 11 (1 HA vs 10 NHW) total deaths. The Hispanic Americans Prostate Cancer Comprehensive Genomic Profiling Study's (THAPCA-GPS) future investigations aim to delineate the pathogenetic differences between HA and NHW and may reduce healthcare disparities and improve clinical outcomes in HA patients.