Racial disparities in risk of second primary malignancies in esophageal cancer survivors: Insights from a population-based database.

Abstract

e16090 Background: Racial disparities shape outcomes in esophageal cancer, yet their role in second primary malignancies (SPMs) remains underexplored. Using a population-based database, this study investigates variations in SPM risk among racial groups, providing critical insights into inequities that influence survivorship, guide surveillance, and inform strategies to reduce disparities. Methods: We analyzed the Surveillance, Epidemiology, and End Results (SEER) database, comparing secondary cancer rates among esophageal cases diagnosed from 2000 to 2022. A second primary malignancy was defined as a malignancy developing six or more months after an index HCC diagnosis. We used the SEER MP-SIR session to obtain the p-value, observed/Expected (O/E) ratio, and absolute excess risk (AER) per 10,000. We excluded patients with unknown race. Results: total of 67,461 SPMs were observed in our extracted cohort. The collective standardized incidence of SPMs was 1.13 (95% CI 1.12-1.14) compared to the US population, with an AER of 21.40 per 10,000 individuals. Most common sites of SPMs included colorectal (SIR 2.17, CI 2.13-2.21), lung (SIR 1.11, CI 1.90-1.14), kidney (SIR 1.11, CI 1.06-1.16), thyroid (SIR 1.67, CI 1.57-1.76), and chronic myeloid leukemia (CML) (SIR 1.21, CI 1.08-1.37). Based on race, the highest risk of SPM was observed in non hispanic American Indian/Alaska native (SIR 1.97 CI 1.77-2.20), while the lowest risk of SPM was observed in hispanic (SIR 1.03 CI 1.01-1.06). Non hispanic whites had an SIR of 1.10 (CI 1.09-1.11), non hispanic blacks SIR 1.22 (CI 1.19-1.25), while non hispanic asian or pacific islander SIR 1.41 (CI 1.37-1.45). Conclusions: Our findings highlight significant racial disparities in second primary malignancy risk among esophageal cancer survivors. In our study, highest incidence of SPMs were found in NHAIAN and NHAPI populations. These differences underscore the need for tailored surveillance strategies and equitable access to care. Addressing such inequities is essential to improving outcomes, guiding prevention efforts, and shaping policies that advance health equity in survivorship.