Abstract 6107: Survival differences by socioeconomic status in Merkel cell carcinoma: A retrospective analysis using the National Cancer Database

Abstract

Abstract Introduction: Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer whose incidence and survival outcomes demonstrate disparities based on patients’ socioeconomic status (SES). This study aims to evaluate the impact of SES on MCC diagnosis age, comorbidity burden, treatment modalities, and survival outcomes using the National Cancer Database. Methods: We conducted a retrospective analysis of 9742 patients diagnosed with MCC from 2016 to 2020 in the United States. To assess how socioeconomic status influences outcomes, a composite score was created by adding income and education quartile assignments (1, 2, 3, 4), to create new composite SES quartiles of 2-3, 4-5, 6-7, and 8. Patients were stratified into quartiles based on their SES (lowest Q1 to highest Q4). Binomial test was performed for categorical variables and ANOVA was performed for continuous. Survival differences were examined with Cox proportional hazards models and Kaplan-Meier curves. Results: Patients with lower SES presented with MCC at younger ages, with the average age of patients in the lowest SES Q1 being 73.8 years (95% CI 73.15-74.35) and the highest SES Q4 being 75.0 years (95% CI 74.48-75.46). Patients in SES Q1 also had higher Charson-Deyo scores, indicating more comorbidities than patients in SES Q4 (8.41% vs 5.8%, p < 0.001). They were also more likely to have advanced stage 4 MCC (9.67% vs 7.79%, p < 0.01) compared to patients in SES Q4. When treated with surgery, patients in SES Q1 were more likely to be treated with local tumor excision (14.39% vs 10.83%, p < 0.001) whereas patients in SES Q4 were more likely treated with Mohs surgery (5.02% vs 3.56%, p < 0.01). Survival probabilities for patients SES Q1 were worse at 1 year (82.99% vs 85.81%, p<0.001), 3 years (61.18% vs 68.49%, p < 0.001) and 5 years (45.99% vs 55.09%, p < 0.001) compared to patients in SES Q4. Conclusion: This study highlights disparities in age at diagnosis, comorbidities, treatment, and survival outcomes in MCC patients based on SES. Patients in lower SES quartiles are diagnosed younger, bear higher comorbidity burdens, and have worse rates of survival. Citation Format: Rachel C. Chang, Elise K. Brunsgaard, David Reid. Survival differences by socioeconomic status in Merkel cell carcinoma: A retrospective analysis using the National Cancer Database [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6107.