Thyroid Transcription Factor-1 Expression in Adenocarcinoma Lung and Its Association with Histomorphological Features

Abstract

Abstract Objectives: Thyroid transcription factor-1 (TTF-1) expression is frequently associated with adenocarcinoma lung. This study was undertaken with the objectives to assess the expression of TTF-1 in non-small cell lung carcinoma (NSCLC) with adenocarcinoma phenotype and to evaluate the TTF-1 expression with clinicopathological and histomorphological features. Materials and Methods: This was a tertiary care hospital-based case series that included 250 cases of NSCLC. TTF-1 immunostaining along with a basic panel of immunohistochemistry markers was performed. The histomorphological analysis was done to compare the morphological features of TTF-1-positive versus TTF-1-negative cases. Results: TTF-1 was positive in 144 cases (57.6%), while 106 cases were negative for TTF-1. The M: F ratio in the TTF-1-positive group was 1:2, and the mean age of the cases that expressed TTF-1 was 48.5 years. The most common pattern in the TTF-1-positive group was loose clusters or singly dispersed cells (77.78%), followed by the acinar (54.86%) and solid pattern (42.36%). In the TTF-1-negative group, 86.79% of cases had singly dispersed cells or loose cohesive clusters, followed by a solid pattern in 50.94% cases. Conclusion: TTF-1 is a useful and reliable marker for pulmonary adenocarcinoma. TTF-1 expression does not have any association with the patterns and degree of differentiation evident in the tumor.