Lung neuroendocrine tumors: pathological characteristics

Abstract

Lung neuroendocrine tumors (NETs) are a heterogeneous family of neoplasms comprising four histologic types, namely typical and atypical carcinoid (TC and AC), large-cell neuroendocrine and small cell carcinoma (SCC). Classification criteria include the number of mitoses per 2 mm, the occurrence and extent of necrosis, cytological and histological features and immunohistochemistry for neuroendocrine markers. The classification system and the diagnostic workflow of lung NETs are apparently easy to apply and well established. However, several unresolved issues still exist in classification and pathological characterization of these tumors, probably because inter-observer diagnostic reproducibility remains disappointing, likely due to inconsistency in recognizing necrosis, mitoses and cytological details, especially in small biopsy or cytological materials. Furthermore, the lack of strong prognostic and grading criteria leads to the incomplete interpretation of some rare intermediate entities that stand in between AC and large cell neuroendocrine carcinoma (LCNEC) categories.

Outcomes of Patients with Clinical Stage I-IIIA Large-Cell Neuroendocrine Lung Cancer Treated with Resection

“…LCNEC was a rare histologic type of lung cancer with an incidence of approximately 3%, while SCLC was a common histologic type of lung cancer accounting for 15-20% of all lung cancers [1,41]. Compared with carcinoid, LCNEC and SCLC had higher mitotic rates, more necrosis and poorer prognosis, and could even manifest combined with other lung cancer types [42]. Although LCNEC and SCLC shared several similar clinical and histologic features, questions remained as to whether it was reasonable to classify LCNEC and SCLC within the same category.…”

Prognostic factors of patients with pulmonary large-cell neuroendocrine carcinoma after surgery: a competing risk analysis

“…Pulmonary LCNEC is a rare primary malignant tumor with a poor prognosis [15,16]. The clinical and biological characteristics of pulmonary LCNEC were similar to small cell lung carcinoma, but standard treatment management has not yet been established.…”

Comprehensive Analysis of Potential Key Genes in Progression of Large Cell Neuroendocrine Lung Carcinoma

“…It is a rare form of aggressive lung cancer with an extremely high proliferation rate [1]. This type of lung cancer occurs more frequently in male smokers who smokes heavily, whereas uncommon in females who do not smoke [2].LCNEC is often categorized in the NSCLC group. However, it is also a member of the lung neuroendocrine tumor (NET) group [3] because it arises from lung cells of neuroendocrine system.…”