Immunohistochemical evaluation of vimentin aberrant expression in lung carcinoid tumors

Abstract

Objective: to the study of the vimentin aberrant expression in the carcinoid tumors of lung, which is a rare group of epithelial neuroendocrine neoplasms with common morphological characteristics and highly variable clinical course.Materials and methods. Vimentin expression was studied using immunohistochemical analysis in neoplasms of 34 patients with lung carcinoid tumors, which included 17 cases in the categories of typical and atypical carcinoids.Results. Overall positive cytoplasmic immunoreactivity was observed in 9 (26.5 %) of the 34 studied tumors. Staining for vimentin was positive in 2 (11.8 %) of typical carcinoid and in 7 (41.2 %) of atypical carcinoid specimens. Expression of vimentin was more often observed in the atypical carcinoids category and was significantly associated with increased grade (p = 0.05), and cell proliferation taking into account the Ki-67 index (p = 0.008).Conclusion. These results suggest that expression of vimentin as an epithelial-mesenchymal transition-related marker plays an important role in the progression of carcinoid tumors. It may prove useful for diagnostic purposes, and also be used as a potential criterion for prognosis assessment of this type of tumors.

Keywords

• lung carcinoid tumor
• vimentin
• immunohistochemistry
• diagnosis