Pulmonary neuroendocrine/carcinoid tumors: a review article

Neuroendocrine tumors are a unique malignant neoplasm that can arise from the respiratory tree. Although well-differentiated bronchial neuroendocrine tumors (also called carcinoid tumors) are reported to account for approximately 25% of all neuroendocrine tumors, they represent only 1% to 2% of all lung cancers. The epidemiology, clinical behavior, and treatment of neuroendocrine carcinoid tumors differ significantly from other lung malignancies. In this article, the recent data regarding these tumors were reviewed with attention to the treatment modalities used. Although conventional cytotoxic therapy has not been reported to demonstrate much promise in this entity over the past 4 decades, newer molecular targeted agents including those that targeted angiogenesis and the mammalian target of rapamycin (mTOR) pathway have shown encouraging results in early phase trials for advanced carcinoid tumors.