Sakamaki Yasushi, Tanaka Ryo, Ishida Daisuke, Tsuji Hiromi, Mike Asako, Yasuoka Hironao
Department of Chest Surgery, Osaka Police Hospital, Kitayamacho 10-31, Tennoji, Osaka, 543-0035, Japan.
Department of Diagnostic Pathology, Osaka Police Hospital, Osaka, Japan.
Surg Case Rep. 2021 Jan 6;7(1):12. doi: 10.1186/s40792-020-01094-3.
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.
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.
This report provides additional knowledge on thymic pigmented carcinoids and thymic atypical carcinoids in elderly patients.
色素性类癌是类癌的一种极其罕见的变体，其特征为肿瘤有黑色素沉着，文献中仅描述了5例。此外，胸腺类癌在老年患者中罕见，类癌肿瘤切除后的预后尚不清楚。
一名82岁男性被诊断为急性胸腔积脓，偶然发现前纵隔肿瘤。该肿瘤最有可能被认为是无创性胸腺瘤或胸腺癌，在积脓消退后需进行手术。积脓手术后4个月，肿瘤被完全切除，患者术后恢复顺利。切除标本的切面广泛色素沉着，呈深褐色，在梭形肿瘤细胞中后来证实有丰富的黑色素沉着。基于组织学检查和免疫组化研究，排除黑色素瘤作为鉴别诊断，该肿瘤被诊断为胸腺色素性非典型类癌。
本报告提供了关于老年患者胸腺色素性类癌和胸腺非典型类癌的更多知识。
