Prognostic factors in inoperable adenocarcinoma of the lung: a multivariate regression analysis of 259 patients

Abstract

The prognostic factors for survival in advanced adenocarcinoma of the lung were investigated in a consecutive series of 259 patients treated with chemotherapy. Twenty-eight pretreatment variables were investigated by use of Cox's multivariate regression model, including histological subtypes and degree of differentiation, the new international staging system for lung cancer, and seven laboratory parameters. Staging of the patients included bone marrow examination but were otherwise nonextensive without routine bone, liver, and brain scans. Factors predicting poor survival were low performance status, stage IV disease, no prior nonradical resection, liver metastases, high values of white blood cell count, and lactate dehydrogenase, and low values of asparatate aminotransaminase. The nonradical resection may not be a prognostic factor because of the resection itself but may rather serve as an indicator for patients having minimal disease spread. Liver metastases were of limited clinical value as a prognostic factor because they were detected in only seven cases in this patient population. A new Cox analysis ignoring the influence of this variable revealed no other variables than those occurring in the former Cox model to be of importance (performance status, stage, surgical resection, WBC, aspartate aminotransaminase, and lactate dehydrogenase). This simplified model appears to be a feasible clinical tool, allowing for prognostic stratification of patients when first the inoperability of the patient is known.