Lung neuroendocrine tumors: A systematic literature review (Review)

Neuroendocrine tumors (NETs) can have multiple localizations in the human body however, most often, it appears in the in thorax at tracheobronchial tree and the thymus. NETs are a group of tumors with heterogenous malignancy that evolve from neuroendocrine cells, with the lung being the second target organ after the gastrointestinal tract. These rare tumors are usually asymptomatic and non-functional with little information regarding incidence in the specialty literature. The main purpose of this review, was the analysis of the available literature in all aspects while mainly focusing on molecular diagnosis data and secondly, by using this molecular landscape to establish a differentiation of lung neuroendocrine tumors (LNETs). By analyzing the literature, new data were revealed regarding histological evaluation, genetic aberrations, prognosis depending on the type of LNET and therapeutic options that derive from these. Efficient management of these tumors is essential in the handling of symptoms and increase in life expectancy, especially in patients with functional tumors. Histological differentiation of LNETs is important in establishing proper therapeutic options and prognosis. Combined types of LNETs remain a controversial topic of discussion regarding diagnosis and treatment, a topic on which further studies are required in order to improve diagnosis in this group of tumors with heterogenous malignancy.