Benign tumors and tumorlike conditions of the lung.

Abstract

Abstract Context.—Benign tumors and tumorlike conditions of the lung are encountered in the pathologic evaluation of asymptomatic and symptomatic lung nodules. Since many of these lesions are uncommon, they can be diagnostically challenging. Objective.—To review the current classification of benign lung tumors, with emphasis on histopathology and useful ancillary studies. Data Sources.—The current World Health Organization classification system for lung neoplasms and review of relevant publications. Conclusions.—Despite improved imaging techniques, benign lung nodules are encountered in wedge biopsy and resection specimens. Histopathology, immunohistochemistry, and molecular techniques ensure accurate pathologic diagnosis and have shed light on the histogenesis of these unusual lesions.