Primary neuroendocrine tumours of the thymus: a clinicopathologic and prognostic study in 19 patients.

BACKGROUND: We sought to evaluate factors influencing long-term survival in 19 patients with primary neuroendocrine tumours of the thymus. METHODS: From January 1990 to December 2004, 19 patients (14 males, 5 females; mean age 48.6 years) were surgically treated for a primary neuroendocrine tumour of the thymus. RESULTS: All patients underwent radical R0 thymomectomy and were followed up for a total of 1,459 months (median: 69 months; range: 8-180). Nine patients had associated paraneoplastic syndrome. No operative mortality occurred. Two patients underwent re-do surgery because of local recurrence, respectively, 25 and 35 months after surgery. Five patients died of disease, respectively, 51, 70, 95, 131 and 153 months after surgery. One patient died of myocardial infarction with no evidence of disease. Thirteen patients are alive, of which 10 are free from disease and three with disease. The overall 5-year and 10-year actuarial survival rates were 91.6% and 69.8%, respectively (median survival: 153 months). The 10-year survival was evaluated according to histology (typical carcinoid 100%; atypical carcinoid: 66.6%; large cell neuroendocrine tumours: 0%), Masaoka staging (stage I: 100%; stage II: 50%; stage III: 66.6%; stage IV: 0%), presence of paraneoplastic syndrome (no: 87.5%; yes: 0%) and postoperative radiotherapy (yes: 40%; no: 83.3%). CONCLUSIONS: The prognosis of primary neuroendocrine tumours of the thymus is related to the grading of the neoplasm, the presence of a paraneoplastic syndrome and to the Masaoka staging but not to the postoperative radiotherapy.