Background: Lung cancer is the most common fatal malignant neoplasm of both men and women. It is usually caused by tobacco smoke. However, at present there is no systematic approach to early diagnosis. The diagnosis of lung cancer is usually made by standard chest roentgenograms and biopsy by bronchoscopy or surgery. Survival rates at 5 years have remained 10% to 15% for the past 30 years with this conventional approach to diagnosis.
Methods: Fifty-one men and women, aged 46 to 81 years (mean age, 64.2 years), with roentgenographically occult cancer were identified in one community hospital by means of sputum cytologic testing. Cancers were diagnosed by means of one or more standard light fiberoptic bronchoscopic procedures with biopsies.
Results: Forty-four squamous cell carcinomas, three adenocarcinomas, two large-cell carcinomas, and two undifferentiated carcinomas were found. Forty-five (86%) were stage 0 or 1. Surgical cure was attempted in 27 patients, and there were three actuarial cancer deaths at 5 years and a total of nine deaths. Additionally, 19 patients received attempts at curative radiation therapy for various reasons, which were usually poor pulmonary or cardiac function or advanced age. Of both the 27 patients who underwent surgery and the 19 who were treated with radiation therapy (total, 46), the actuarial results by the life-table method included nine lung cancer deaths in 5 years and 21 deaths from all causes, giving an actuarial survival, including deaths from all causes, of 55%.
Conclusion: Roentgenographically occult lung cancer can be found by sputum cytologic testing followed by fiberoptic bronchoscopy and biopsy at a time when cure is more likely than when it is diagnosed by conventional roentgenographic techniques (ie, 55% survival vs 10% to 15% survival). Sputum cytologic testing should be used as a case-finding tool, particularly in heavy smokers and those with occupational risks. This diagnostic approach to earlier diagnosis and intervention can be successful in a small community hospital.