Surgical resection of micronodular thymic carcinoma with lymphoid hyperplasia: a case report

Abstract

Abstract Background Micronodular thymic carcinoma with lymphoid hyperplasia is an extremely rare thymic tumor, exhibiting a variety of cell morphologies with mild to severe dysmorphism. Since few cases have been reported, the prognosis of this disease is unclear. Case presentation A 55-year-old woman was referred to our hospital with an anterior mediastinal tumor. She was incidentally detected with a tumor in a medical examination. We diagnosed the patient with thymic carcinoma or thymoma and performed surgery via median sternotomy. Histologically, tumor cells showed weakly acidic vesicles and bright nuclei, including small nucleoli. Most of the tumor cells were cluster of differentiation (CD)5-positive, CD3-negative, and terminal deoxynucleotidyl transferase (TdT)-negative. Conclusions Based on these histological findings, the resected specimen was diagnosed as micronodular thymic carcinoma with lymphoid hyperplasia. The patient’s postoperative course was uneventful, and no signs of recurrence were observed at 5 years after the surgery.