Objective Measurements of Physical Function to Predict Survival in Patients with Metastatic Cancer

Abstract

Background/Objectives Physician-reported performance status (PS) constitutes the established method for stratifying oncologic patients in therapeutic decision-making. Objective measurements of physical function may further refine prognostication. Subjects/Methods In this prospective observational study, 103 patients with metastatic cancer who were referred for systemic therapy initiation were evaluated. PS was evaluated using the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) and five objective physical function measurements (handgrip strength [HGS], chair stand test [CST], timed up and go [TUG] test, 4-m gait speed [GS] test, and short physical performance battery [SPPB] test). Overall survival and treatment complications were recorded from the medical records. Results Patients with low PS according to ECOG-PS (hazard ratio [HR]: 3.80, 95% confidence interval [CI]: 1.84, 7.80), HGS (HR: 2.37, 95% CI: 1.24, 4.55), SPPB (HR: 3.43, 95% CI: 1.55, 7.57), GS (HR: 3.03, 95% CI: 1.44, 6.38), and TUG (HR: 5.16, 95% CI: 2.19, 12.14) had shorter overall survival after adjustment for sex, age, symptomatology, comorbidity, percentage of weight loss, and tumor localization. Conclusions Among the studied objective physical function measurements, HGS, SPPB, GS, and TUG were independent predictors of survival in a sample of patients with metastatic cancer, with TUG showing the highest effect size.