Incidence, epidemiological characteristics, and cause-specific survival analysis of ampullary carcinoma using the SEER database.

Abstract

4168 Background: Ampullary carcinomas (AC) are rare and comprise only 0.2% of gastrointestinal malignancies, and there is a paucity of studies analyzing them. We studied the incidence, demographics, tumor characteristics, and survival variables of patients with AC using the Survival, Epidemiology, and End Results [SEER] November 2021 database. Methods: We identified 3650 patients aged >18 with microscopically confirmed adenocarcinoma of the ampulla using ICD-O-3 site code C241 and histology codes (8140-8147, 8480, 8490, 8500). The epidemiological characteristics and the survival variables included were age, gender, ethnicity, and American Joint Committee on Cancer [AJCC] Staging. The overall 5-year survival (OS), cause-specific 5-year survival (CSS), and CSS plots across different strata were plotted using the Kaplan-Meier Method. The analysis was done using the Cox proportional hazard regression model (p<0.05). Results: The overall age-adjusted incidence of AC was 0.3 per 100,000 cases. The median age at diagnosis was 69 (Interquartile range - 59, 78). It was more common in males (56.03%) and Non-Hispanic White (58.96 %), with the most common stages at a presentation being stage 2B IIB (22.08%) and stage III (22.11%). The observed overall 5-year survival was 31%, and the cause-specific 5-year survival was 37.5%. The CSS was not significantly associated with gender (p=0.06). The estimated hazards of death attributed to AC increase by 13% (p < 0.0001) for every 10-year increase in age at diagnosis above 67 years. The CSS was also associated with race, with African Americans and Hispanics being associated with higher hazards of death attributed to AC when compared to Non-Hispanic Whites with HR of 1.5 (p<0.0001) and 1.12 (p=0.01), respectively. Conclusions: Ampullary carcinoma is more commonly seen in males and non-Hispanic Whites with a median age of 69 years. Patients are typically diagnosed in stages IIB and III. Lower CSS rates were associated with advancing age, African American, and Hispanic populations. We need further studies to determine whether these disparities between different races are due to socioeconomic, genetic, or biological factors. Additional studies investigating how different treatment options affect AC survival, especially in this population subset, can be explored. [Table: see text]