Introduction

Abstract

Pulmonary cytopathology has evolved over the last century and half. The first report on identification of cancer cells in sputum is found in a publication by Walshe in London in 1845. The second half of the nineteenth century saw several studies on cancer cells in sputum. This methodology, however, remained dormant in the early years of the twentieth century, only to be revitalized by the works of George Papanicolaou in 1928 and his landmark publication with Traut in 1943 on cervical cancer diagnosis. Respiratory cytology followed the lead of cervical—vaginal cytology taking a revolutionary turn and gained tremendous popularity as noted by the voluminous literature on the subject since. The 1950s and 1960s were earmarked for rapid development in respiratory cytopathology. The application of sputum cytology was expanded to retrieval of samples under direct vision via a rigid bronchoscope. The subsequent development of a flexible fiberoptic bronchoscope facilitated the procedures, permitting visualization of bronchi to the third and fourth order and obtaining specimens for cytologic evaluation. This substantially enhanced the diagnostic yield.