A 35-year retrospective study of carcinoid tumors in Taiwan - Differences in distribution with a high probability of associated second primary malignancies

BACKGROUND. A comprehensive study of carcinoid tumors from United States-based databases indicated that the small intestine, colon, rectum, and bronchopulmonary system are common locations for carcinoid tumors. In addition, certain carcinoid tumors, such as rectal carcinoids, appeared to be overrepresented in nonwhite populations in the United States. High frequencies of associated noncarcinoid malignancies were reported in some articles. The objective of the current study was to address the organ distribution, frequency of metastasis, and survival rates of carcinoid tumors and the associated noncarcinoid tumors in Taiwanese, Asian populations. METHODS. Two hundred twenty-eight patients with carcinoid tumors were identified and evaluated from the surgical pathology files and medical records of the Veterans General Hospital, Taipei, Taiwan from January 1970 to December 2005. RESULTS. In 228 carcinoid tumors that were analyzed, the rectum (60.5%) was the most common location followed by the lung (20.2%) and the thymus (6.6%). Metastatic lesions were demonstrated in 16.2% of patients. Disease extent was associated with survival. The 5-year survival rates for patients with localized, regional metastatic, and distant metastatic disease were 94.1%, 49.1%, and 0%, respectively (P < .001). Associated noncarcinoid malignancies were noted in 14% of patients with carcinoids, mainly in the gastrointestinal tract (52.9%), lung, and genitourinary system. CONCLUSIONS. A different organ distribution of carcinoids was observed in Taiwanese patients, who had with significantly more carcinoids located in the rectum and thymus compared with patients in Western countries. The patients with carcinoids in the current study had a high possibility of developing associated, noncarcinoid neoplasms. Surveillance of the colon, stomach, lung, and genitourinary system for second malignant tumors is recommended.