Open Access Original Article

Lung carcinoid tumor is a type of neuroendocrine tumor, which is subdivided into typical carcinoid (TC) and atypical carcinoid (AT), based on the rate of mitosis and the presence of necrosis. Several prognostic factors for lung carcinoids have been reported in the literature, including the type, Ki67 index, stage, chemotherapy and radiation therapy. In the present study, 108 cases with resected carcinoid lung tumors were enrolled and the expression of CD56, thyroid transcription factor 1, synaptophysin, carcinoembryonic antigen, epithelial membrane antigen and neuron-specific enolase (NSE) in the resected tissue specimens was immunohistochemically analyzed. Patients with positive staining for NSE had an unfavorable survival prognosis compared with patients with negative staining for NSE (137.2 vs. 150.0 months, P=0.044). According to univariate analysis, none of the above immunohistochemistry markers was associated with survival, and according to multivariate analysis, NSE was an independent influencing factor for survival inpatients with AT (P=0.046) and furthermore, the stage was an independent factor of survival in patients with TC (P=0.005).