Yasushi Sakamaki1, Ryo Tanaka2, Daisuke Ishida2, Hiromi Tsuji3, Asako Mike3, Hironao Yasuoka3. 1. Department of Chest Surgery, Osaka Police Hospital, Kitayamacho 10-31, Tennoji, Osaka, 543-0035, Japan. sak@serenade.plala.or.jp. 2. Department of Chest Surgery, Osaka Police Hospital, Kitayamacho 10-31, Tennoji, Osaka, 543-0035, Japan. 3. Department of Diagnostic Pathology, Osaka Police Hospital, Osaka, Japan.
Abstract
BACKGROUND: A pigmented carcinoid is an extremely rare variant of carcinoid characterized by melanin pigmentation of the tumor, with only five cases described in the literature. In addition, thymic carcinoids are rare in elderly patients and their prognosis after resection of the carcinoid tumor is unclear. CASE PRESENTATION: An anterior mediastinal tumor was incidentally found in an 82-year-old man who had been diagnosed with acute thoracic empyema. The tumor was considered most likely to be a noninvasive thymoma or thymic carcinoma for which surgery was indicated after the resolution of the empyema. The tumor was completely resected 4 months after the empyema surgery, and the patient had an uneventful postoperative course. A cut surface of the resected specimen was extensively pigmented and appeared dark-brownish, with abundant melanin pigmentation later confirmed in the spindle-shaped tumor cells. Based on the histologic examination and immunohistochemical study, melanoma was eliminated as a differential diagnosis and the tumor was diagnosed as a pigmented atypical carcinoid of the thymus. CONCLUSIONS: This report provides additional knowledge on thymic pigmented carcinoids and thymic atypical carcinoids in elderly patients.
BACKGROUND: A pigmented carcinoid is an extremely rare variant of carcinoid characterized by melaninpigmentation of the tumor, with only five cases described in the literature. In addition, thymic carcinoids are rare in elderly patients and their prognosis after resection of the carcinoid tumor is unclear. CASE PRESENTATION: An anterior mediastinal tumor was incidentally found in an 82-year-old man who had been diagnosed with acute thoracic empyema. The tumor was considered most likely to be a noninvasive thymoma or thymic carcinoma for which surgery was indicated after the resolution of the empyema. The tumor was completely resected 4 months after the empyema surgery, and the patient had an uneventful postoperative course. A cut surface of the resected specimen was extensively pigmented and appeared dark-brownish, with abundant melaninpigmentation later confirmed in the spindle-shaped tumor cells. Based on the histologic examination and immunohistochemical study, melanoma was eliminated as a differential diagnosis and the tumor was diagnosed as a pigmented atypical carcinoid of the thymus. CONCLUSIONS: This report provides additional knowledge on thymic pigmented carcinoids and thymic atypical carcinoids in elderly patients.