Determinants of long term survival after surgery for cancer of the lung - A population-based study

BACKGROUND, Even if some determinants of lung cancer (LC) prognosis have be en established, their independent effect on long term survival remains to b e seen. The objective of the current study was to identify the prognostic i ndicators of long term survival among LC patients treated by surgery. METHODS, All patients with LC recorded at the Geneva Cancer Registry betwee n 1977 and 1987 were analyzed by logistic regression, considering as cases (n = 98) those patients alive 10 years after their initial diagnosis and as controls (n = 330) all other patients, excluding those who did not undergo putative curative surgery. The effect of each prognostic factor was evalua ted after accounting for age and gender ("crude" effect) and also for other a priori confounding factors (adjusted effect). Additional models consider ed two staging variables simultaneously to identify the strongest staging d eterminant. Results were presented as relative risk estimates of long term (greater than or equal to 10 years) survival. RESULTS, Age, histology, and stage of disease significantly influenced prog nosis regardless of the confounding factors considered. Gender also emerged as a discriminated factor in LC outcome, with a 2.1-fold increased chance (95% confidence interval, 1.6-3.5) of long term survival for women compared with men. Method of discovery, presence of symptoms, period of diagnosis, socioeconomic status, and tumor differentiation did not appear to be associ ated with long term survival. Extent and size of the tumor were found to be the most reliable prognostic staging factors, whereas adenopathy had no ef fect after accounting for extension. CONCLUSIONS, The current population-based study quantifies the independent effect of the factors modifying the chances of curability in patients with LC. In particular, it provides additional evidence that gender strongly inf luences long term survival. (C) 1999 American Cancer Society.