The KPROCS Study: A Real-World and Research Resource to Investigate Multilevel Determinants of Ovarian Cancer Treatment and Survival.

BACKGROUND: Compared with non-Hispanic White (NHW) women, Black women with epithelial ovarian cancer (EOC) experience poorer survival, partly due to differences in treatment and access to care. However, these factors do not fully explain survival disparities, and outcomes among other groups remain understudied. Emerging evidence also suggests racial differences in molecular subtypes. The Kaiser Permanente Northern California (KPNC) Research on Ovarian Cancer Survival (KPROCS) Study was established to evaluate how multilevel factors contribute to differences in EOC treatment and survival. METHODS: KPROCS includes women diagnosed at KPNC between 2000 and 2022 with invasive epithelial ovarian, fallopian tube, or peritoneal cancers at age ≥18 years. Diagnostic slides underwent centralized pathology review to classify histotypes according to the 2020 WHO criteria. Addresses at diagnosis were linked to geospatial data to assess healthcare accessibility to chemotherapy infusion centers and neighborhood characteristics. In 540 women with high-grade serous EOC, gene expression molecular subtypes are being characterized. RESULTS: The cohort includes 6,067 women with EOC, including 359 Black, 798 Hispanic, 906 non-Hispanic Asian American and Pacific Islander (AAPI), and 3,971 NHW women. Descriptive analyses demonstrate subpopulation differences that may influence survival. For example, Black women were least likely to receive surgery (75%), while AAPI women were the most likely (91%). Overall, 19% of the cohort received neoadjuvant chemotherapy, with the highest proportion among Black women (25%). CONCLUSIONS: This integrative approach will provide new insights into persistent differences in EOC treatment and survival across population subgroups. IMPACT: KPROCS is a unique resource for EOC disparities research.