Prognostic factors for survival of patients with extensive stage small cell lung cancer--a retrospective single institution analysis.

The objective of this retrospective study was to investigate prognostic factors associated with survival of patients with extensive stage small cell lung cancer (ES-SCLC). Included were 200 patients admitted to the Liberation Army General Hospital with a diagnosis of ES-SCLC. The demographics of patients, disease characteristics, pre-treatment biochemical parameters and therapeutic plan were assessed or evaluated. Univariate analysis found that second-line chemotherapy, radiotherapy, and no liver metastasis were associated with improved survival. Tumor response to first-line chemotherapy and normal initial hemoglobin levels were also associated with a survival benefit (all P-values ≤ 0.0369). Multivariate Cox regression analysis indicated that liver metastasis and the total number of all chemotherapy cycles were independent prognostic factors of survival. The morbidity risk in patients with liver metastasis was 2.52-fold higher than that in patients without liver metastasis (hazard ratio (HR)=2.52 (1.69-3.76); P<0.0001). However, one unit increase in the total number of chemotherapy cycles decreased the risk of death by 0.86-fold (HR=0.86 (0.80-0.92); P<0.0001). Absence of liver metastasis and ability of a patient to receive and tolerate multiple lines of chemotherapy were associated with longer survival.