Abstract
BACKGROUND: We have limited information about neuroendocrine carcinoma (NEC) of the gallbladder. The purpose of this paper is to compare clinical and pathological features between different age groups and prognostic factors for gallbladder NEC and how it differs from adenocarcinoma (ADC) of the gallbladder. PATIENTS AND METHODS: This study included 28 gallbladder NEC patients and 137 ADC patients whose clinical characteristics and pathological findings were retrospectively collected. Propensity score matching and Cox regression analysis were used for the analysis of prognostic factors. RESULTS: We divided NEC patients into two groups based on the age more than or less than 60 years. Most of the NEC patients less than 60 years old complained of abdominal pain or discomfort (p = 0.038), and more younger patients accepted adjuvant therapy (p = 0.020) than older patients did. CD56 was positive in all patients more than 60 years old, which is significantly higher than that of younger patients (p = 0.039). The mean age was similar between NEC and ADC patients. After eliminating confounding factors between NEC and ADC patients, the overall survival rates were still lower in NEC patients. Univariate analysis extracted six possible risk factors. Multivariate analysis indicated that surgery type, tumor size, and existence of gallstones were independent prognostic factors. CONCLUSION: The overall survival of gallbladder NEC is not associated with age. In this study, surgical method and tumor size were found to be independent risk factors for NECs. In addition, NEC patients have a worse prognosis than ADC patients with similar clinical and pathological features.