Thymic neuroendocrine carcinoma: clinicopathological features

Objective To investigate the clinicopathological features of thymic neuroendocrine carcinoma and its differential diagnosis. Methods Clinicopathologic analysis and immunohistochemical staining were performed in 5 cases of TNC. Results For 5 cases TNC, 3 cases occurred in men, 2 cases occurred in women. The average age was 46.8 years. They were with chest symptoms before operation. 3 cases were Ⅱ and 2 cases were Ⅲ by clinic stages. Grossly , the tumors were gray in color with areas of hemorrhage and necrosis. Histopathology of well differentiated 2 cases and poorly differentiated 3 cases. Immunohistochemically, the tumor cells were positive for CK, NSE, SyN and CgA. 3 cases were positive for PCNA, Ki67, p53. Conclusions TNC has a pleomorphic appearance of histological features with well, moderate and poorly-differentiated areas. Immunohistochemical staining is helpful in the differential diagnosis of TNC from other tumors derived from the thymus. Neither grading as neuroendocrine carcinomas nor any individual histologic parameter showed a significant association with prognosis. Initial aggressive treatment, including complete surgical excision and adjuvant radiotherapy, appears to offer the best hope for prolonged survival. Adjuvant chemotherapy also should be considered, because the incidence of distant relapse is high.