The pathology of low and intermediate neuroendocrine lung tumors
Neuroendocrine lung tumors can be grouped into four epithelial and one mesenchymal tumor. The epithelial neuroendocrine tumors are further divided into two high-grade carcinomas, large and small cell neuroendocrine carcinomas, and into low-grade typical and intermediate grade atypical carcinoid. The only non-epithelial neuroendocrine tumor of the lung is pulmonary paraganglioma. In this short review, we will focus on the low and intermediate grade neuroendocrine tumors only. The review will touch on history, terminology, epidemiology, morphology, biology, and prognosis, and very briefly discuss therapeutic aspects. This review does not intend to completely discuss the vast amount of literature written on this subject, but will only cite the most relevant literature data.