Rising incidence of neuroendocrine tumors in Singapore: An epidemiological study

Abstract

Aim: The incidence of neuroendocrine tumors (NETs) is increasing worldwide. This study presents the epidemiological trends of NETs and survival results from Singapore. Materials and methods: This is a retrospective population-based study of all NETs treated during 1993–2014 in Singapore. The primary outcome studied was trends in incidence of NETs, and secondary outcomes were gender, ethnic and histological variations, and overall survival results. Results: During the study period, 1,725 cases were identified and the age-standardized incidence increased from 0.8 to 3 per 100,000 per year. The mean age of diagnosis was 56.0 (±25.5) years, with the highest incidence among ethnic Chinese (n = 1391, 80.6%) and gender ratio nearly 1:1. Histologically, the tumors were predominantly carcinoid tumor (52.6%) and neuroendocrine carcinoma (40.3%), with tumors arising most commonly in the rectum (26.0%), colon (13.7%), lung and bronchus (13.7%), pancreas (9.4%), stomach (7.1%), small intestine (5.9%), and other organs (24.1%). Majority were G1 (51.9%) and G3 (33.9%) tumors, and of clinical stage I (41.0%) and stage IV (35.9%). The most commonly rendered treatment was surgery alone (36.2%). The 5-year overall survival for the cohort for all NETs was 38.1%, and 10-year survival was 22.0%. Predictors for poor survival in this cohort include primary tumor site, gender, and advancing age. Conclusion and clinical significance: The incidence of NETs in Singapore has markedly increased nearly fourfold over the last two decades, possibly due to improved detection. However, there are various other unevaluated factors that warrant further investigation.