Thymic carcinoid tumor--a report of 7 cases.

The thymic carcinoid tumor is a rare neoplasm which is often clinically misdiagnosed as thymoma. But the two differ in origin, biological behavior, accompanying syndromes, pathological features, and prognosis. The characteristics of the thymic carcinoid tumor are: difficulty in diagnosis, high malignancy, frequent recurrence and extrathoracic metastasis over a prolonged period postoperatively. Complete surgical resection of original and recurrent tumors is the important treatment. Microscopic, electron microscopic and immunohistochemical examinations may be required in making an accurate pathological diagnosis. This paper reports 7 cases of thymic carcinoid tumor.