Demographic and clinicopathological factors impacting survival in malignant carcinoid tumors: A SEER database analysis.

Abstract

e16319 Background: Malignant carcinoid tumors are indolent neuroendocrine neoplasms with generally favorable survival. While prior studies have described outcomes, a comprehensive, contemporary analysis of demographic, socioeconomic, and geographic factors and their impact on survival across all major carcinoid subtypes remains a significant gap in current epidemiological literature. Methods: A population-based cohort study was conducted using the Surveillance, Epidemiology, and End Results (SEER) database (2000-2022). Patients were identified using ICD-O-3 codes for malignant carcinoid tumors: 8240/3, 8243/3, 8245/3, and 8249/3. Overall survival was analyzed using Cox proportional hazard regression performed with GraphPad Prism software, adjusting for key clinicopathological variables. Results: Among 94,867 identified patients (median follow-up 59 months; 27,503 deaths), significant demographic predictors of higher mortality included: older age (≥65 years; HR 1.9, 95%CI 1.3-2.7, p = 0.0003), male sex (HR 1.4, 95%CI 1.3-1.4, p < 0.0001), Black race (HR 1.1, 95%CI 1.1-1.2, p < 0.0001), lower household income ( < $80,000; HR 1.1, 95%CI 1.1-1.2, p < 0.0001), and rural county of residence (HR 1.1, 95%CI 1.0-1.1, p = 0.0013). Predictors of lower mortality included: Asian/Pacific Islander race (HR 0.77, 95%CI 0.71-0.83, p < 0.0001), Hispanic ethnicity (HR 0.91, 95%CI 0.86-0.96, p = 0.0002), and being married or partnered (HR 0.71, 95%CI 0.68-0.73, p < 0.0001). Significant disease/treatment factors for worse mortality included: adenocarcinoid histology (worst outcome; HR 1.9, 95%CI 1.6-2.2), followed by goblet cell carcinoid (HR 1.6, 95%CI 1.5-1.7) and atypical carcinoid (HR 1.4, 95%CI 1.3-1.5), all versus typical carcinoid (p < 0.0001). Distant stage (HR 2.5, 95%CI 2.4-2.6) and regional stage (HR 1.4, 95%CI 1.3-1.4) predicted worse survival versus localized disease (p < 0.0001). Receipt of chemotherapy (HR 1.7, 95%CI 1.6-1.8) or radiotherapy (HR 1.3, 95%CI 1.2-1.3) was associated with higher mortality (p < 0.0001), likely reflecting advanced disease. Surgery had a strong association with better overall survival (HR 0.46, 95%CI 0.44-0.47, p < 0.0001). Conclusions: This large-scale analysis confirms the indolent nature of carcinoid tumors but identifies significant and multifaceted demographic disparities in survival, independent of disease factors. Age, sex, race, socioeconomic status, and geography are significant prognostic variables. Histologic subtype and stage remain powerful determinants. The association of systemic therapy with higher mortality underscores its use in advanced cases, while surgery is strongly associated with improved outcomes. These findings highlight populations at risk and can inform strategies to mitigate survival disparities.