Baseline quality of life and performance status as prognostic factors in patients with extensive-stage disease small cell lung cancer treated with pemetrexed plus carboplatin vs. etoposide plus carboplatin

Abstract

Background: Small cell lung cancer (SCLC) is associated with poor prognosis due to its early metastatic potential and lack of improved outcomes with newer cytotoxic agents. Identifying factors associated with clinical outcomes can help clinicians determine which patients are more likely to benefit from therapy. Functional Assessment of Cancer Therapy (FACT) subscales and Eastern Cooperative Oncology Group performance status (ECOG PS) were retrospectively analyzed as prognostic factors for overall survival (OS) and progression-free survival (PFS) in patients with extensive-stage disease (ED)-SCLC.

Methods: Using data from a Phase III trial of pemetrexed-carboplatin vs. etoposide-carboplatin, the effect of the prognostic factors on OS and PFS was analyzed via Cox models. The Kaplan-Meier method was used to estimate OS and PFS parameters for the prognostic subgroups (defined by baseline FACT scores and ECOG PS).

Results: Patients with higher baseline FACT-General (FACT-G) score (≥ median) had significantly higher OS (hazard ratio [HR]=0.62, P<.0001) and PFS (HR=0.83, P=.032) compared with patients with lower FACT-G score (<median). Similar results were observed for higher baseline physical well-being (PWB) and functional well-being (FWB) scores. For OS, there was a significant interaction between PS and FACT-PWB score (P=.005). In patients with PS=2 and higher FACT-PWB scores at baseline, a 48% reduction in the risk of death (P=.025) and nearly 3-month longer median OS were estimated.

Conclusions: Higher baseline FACT-G, FACT-PWB, and FACT-FWB scores were found to be favorable prognostic factors for survival in ED-SCLC. Higher FACT-PWB scores at baseline predicted better survival for patients with poorer PS.