New horizons in lung cancer diagnosis

Lung cancer is rarely diagnosed and treated while still localized. Sputum cytology allows detection of radiologically occult tumors but conventional endoscopic procedures frequently prove inadequate for localization. It is the purpose of this report to outline the endoscopic observations and methods we have developed in successfully localizing 17 consecutive, radiologically occult carcinomas discovered in the sputum of 15 patients. A detailed examination of the upper respiratory tract demonstrated occult tumors in two patients. A segment by segment fiberbronchoscopic study under anesthesia allows multiple brushings and meticulous handling of specimens. Lesion localization is provided as well as identification of synchronous second primary tumors. Biopsies at the lobar spur and carina assist in determining the proximal extent of carcinoma in situ at potential surgical margins. Newer methods should enhance our recognition of inapparent carcinoma in situ allowing more efficient and more accurate tumor localization and a better appreciation of its extent.