Prognostic factors for patients with small cell lung carcinoma: analysis of a series of 763 patients included in 4 consecutive prospective trials with a minimum follow-up of 5 years.

Abstract

The purposes of this study were to identify prognostic factors for response to chemotherapy, overall survival, and long term survival of patients with small cell lung carcinoma and to construct a classification of patients on the basis of their expected overall survival. In the 763 patients registered in 4 consecutive clinical trials conducted by the European Lung Cancer Working Party from 1982 to 1993, the impact of 21 pretreatment variables assessable in a routine practice was analyzed for the various outcomes with a minimum follow-up of 5 years. The key prognostic role of disease extent was confirmed for all the outcomes. Additional independent prognostic factors for response to chemotherapy were gender, neutrophil count, and hemoglobin level; for overall survival, these factors were Karnofsky performance status, gender, and neutrophil count. Recursive partitioning and amalgamation algorithms (RECPAM) analysis classified patients into 4 groups, taking into consideration disease extent, Karnofsky performance status, age, gender, and neutrophil count. Median survival times for the 4 groups were 60, 47, 36, and 28 weeks, respectively. For long term survival, defined as a minimum survival of 2 years (9% of the patients), Karnofsky performance status was the only independent predictive factor, along with the achievement of a complete response (if this was taken into consideration). Small cell lung carcinoma remained the main cause of death among these patients. Cure was infrequent, with only 14 patients alive and disease free at 5 years (1.8%). In this study the long term prognosis associated with small cell lung carcinoma was poor. The well-known prognostic values of disease extent and Karnofsky performance status were confirmed, but the authors also identified age and gender (which are more controversial) as independent characteristics, in addition to citing the role of complete response in the attainment of long term survival. The independent role of neutrophils observed by the authors. must be validated by further studies.