The impact of the modified frailty index on clinical outcomes for patients with stage IV non-small cell lung cancer receiving chemotherapy.

INTRODUCTION

Frailty impacts outcomes for patients with lung cancer, but no brief tools have been assessed in patients with metastatic disease. We evaluated the impact of the Modified Frailty Index (mFI) on clinical outcomes for patients with metastatic non-small cell lung cancer (NSCLC).

METHODS

We conducted a retrospective cohort study of all patients with Stage IV NSCLC diagnosed in Manitoba between 2011 and 2016 who then received first-line cytotoxic chemotherapy. We assigned mFI scores based on documented comorbidities and collected data on toxicity, progression, and survival. Descriptive statistics characterized the cohort and toxicity experienced. Kaplan-Meier methods were used to evaluate progression-free survival (PFS) and overall survival (OS), followed by multivariable Cox proportional hazards models.

RESULTS

Our cohort of 426 (mFI 0/1-2/3+ = 175/196/55) patients, showed no significant association between higher mFI score and incidence of overall chemotherapy toxicity. Patients with mFI 0 experienced more frequent thromboses (p=0.022) and a trend towards less nausea or vomiting (p = 0.059). There was no significant difference in PFS or OS among frailty groups. Poorer performance status, number of metastatic sites, and the absence of a driver mutation were independently associated with poorer PFS and OS. Male sex and not completing chemotherapy were also associated with worse OS.

CONCLUSION

This study is the first to investigate the use of the mFI as a frailty tool in patients with metastatic NSCLC receiving cytotoxic chemotherapy. The mFI does not appear to be strongly associated with treatment-related toxicities, PFS, or OS in patients with metastatic NSCLC receiving first-line cytotoxic chemotherapy.