Resected thymic large cell neuroendocrine carcinoma: report of a case

BACKGROUND: Thymic large cell neuroendocrine carcinoma (LCNEC) is extremely rare. The detailed clinical features of thymic LNCECs remain unknown. CASE PRESENTATION: A 90-year-old man with a history of diabetes mellitus, chronic renal failure, and an abdominal aortic aneurysm underwent computed tomography for follow-up, which showed an anterior mediastinal tumor, measuring 31 mm × 28 mm in diameter. Magnetic resonance imaging showed an iso-intensity mass on T1-weighted images and high intensity on T2-weighted images. 18F-Fluorodeoxyglucose-positron emission tomography showed marked uptake in the mass, which was diagnosed as invasive thymoma or thymic carcinoma. Video-assisted thoracic surgery through the left thoracic cavity was converted to median sternotomy due to severe adhesions between the left lung and the chest wall. Partial thymectomy and combined partial resection of left upper lobectomy and the first and the second costal cartilages were performed. The pathologic diagnosis was thymic LCNEC, Masaoka stage III. The patient developed pleural dissemination and left lung metastases in 5 months and died 12 months after surgery. CONCLUSIONS: Thymic LCNEC has high malignant potential. More cases need to be studied.