Proximal bronchial extension with special reference to tumor localization in non-small cell lung cancer

Objective: Surgery is the optimal treatment in patients with non-small cell lung cancer (NSCLC) and tumor-negative bronchial resection margins should be maintained for a curative resection. The epidemiology of NSCLC, includin g the aspects of tumor localization, has been changing during the recent de cades. The aim of this study was to evaluate microscopic proximal bronchial extension with special reference to the site of the tumor. Methods: Surgic al specimens of 70 NSCLC cases were examined histologically for proximal br onchial extension of the tumor. The entire bronchial tree with the tumor wa s extracted from the specimen and serially cut at a thickness of 5 mm in th e transverse plane of the bronchus. Microscopic proximal extension of the t umor was classified as either endobronchial or peribronchial. Results: Thir ty-three (47.1 To) tumors had central and 37 (52.9%) had peripheral localiz ation. Among the central and peripheral tumors, 10 (30.3%) and seven (18.9% ) had microscopic proximal extension, respectively. In total, the mean leng th of proximal extension was 10.94 +/- 7.07 mm. The mean length of extensio n for peripheral tumors was 15.71 +/- 8.38 mm, significantly greater than t hat of central tumors, which was 7.60 +/- 3.47 mm (P = 0.026). Peripheral t umors showed a significant peribronchial extension (P = 0.024). Conclusions : A greater percentage of central tumors show microscopic proximal bronchia l extension, whereas the length of microscopic proximal bronchial extension is significantly greater in peripheral tumors. Peripheral tumors preferent ially have a peribronchial extension pattern. (C) 2001 Elsevier Science BN. All rights reserved.