Primary thymic carcinoma with adenoid cystic carcinoma-like features: A case report and literature review

RATIONALE: Thymic carcinoma with adenoid cystic carcinoma-like features is a special subtype of thymic adenocarcinoma, and the occurrence of this condition is extremely rare. Herein, we report a case of primary thymic carcinoma with adenoid cystic carcinoma-like features in a young man. PATIENT CONCERNS: A 38-year-old man had an incidental finding of space-occupying lesion in the anterior mediastinum during a routine health examination. The patient complained of occasional mild chest tightness during hot weather but had no obvious cough, sputum, chest pain, or fever. Contrast-enhanced computed tomography scan of the chest revealed a space-occupying lesion in the anterior mediastinum, which is likely benign. DIAGNOSIS: The lesion was diagnosed as a primary thymic carcinoma with adenoid cystic carcinoma-like features. INTERVENTION: The patient underwent thoracoscopic resection of left anterior mediastinal mass and enlarged resection of thymectomy and mediastinal fat in our hospital. OUTCOMES: The postoperative course was uneventful. LESSONS: The tissue characteristic of this tumor was extremely similar to that of adenoid cystic carcinoma. A precise pathological examination is extremely important to prevent misdiagnoses of the lesion as adenoid cystic carcinoma or other thymic tumors. Immunohistochemical staining is extremely useful for the pathological and differential diagnoses of this tumor.