A rare case of thymic carcinoid detected spontaneous regression

Abstract

A 65-year-old male, complaining of anterior chest pain and fever, demonstrated an abnormal mass at the anterior mediastinum, which reduced from 60 to 15 mm in diameter after antibiotic treatment. Biopsy failed to clarify the diagnosis, and thymoma was strongly suspected due to radiological results. Extended thymectomy was performed. The completely encapsulated tumor was in the thymus, and included necrotic tissue. Microscopic examination with Grimelius staining showed dense-core neurosecretory granules in the cells, indicating carcinoid tumor of the thymus. Spontaneous regression of carcinoid tumor has seldom been reported. There have been no signs of recurrence for more than five years after surgery in this case.