[Intra-thymic Multiple Thymic Cancer:Report of a Case]

We report a rare case of two thymic squamous cell carcinomas arising within the thymus of a 76-yearold woman. Chest computed tomography (CT) performed for evaluation of back pain revealed two enhancing nodules:one in the right lower pole of the thymus and another adjacent to the right margin of the innominate vein. Because of her advanced age and multiple comorbidities, thoracoscopic partial thymectomy was performed for diagnostic and therapeutic purposes. Both tumors were completely resected with negative margins. Histopathological examination showed that both nodules were squamous cell carcinomas. One tumor exhibited invasion into surrounding adipose tissue and venous structures, whereas the other showed no capsular invasion. Based on these findings, distinction between multicentric occurrence and intrathymic metastasis was challenging. The postoperative course was uneventful. No adjuvant therapy was administered, and she remains free of recurrence at one year. This case highlights the diagnostic difficulty of multiple thymic carcinomas and suggests that complete thymectomy may be preferable when general condition permits, given the possibility of microscopic residual disease.