Baseline patient-reported kidney cancer-specific symptoms as an indicator for median survival in sorafenib-refractory metastatic renal cell carcinoma

Introduction The goal of the study was to determine the relationship of baseline Functional Assessment of Cancer Therapy-Kidney Cancer Symptom Index (FKSI) scores with median progression-free survival (mPFS) and median overall survival (mOS) after treatment with axitinib in patients with sorafenib-refractory metastatic renal cell carcinoma. Methods As part of a multicenter, open-label, phase II study, patients (N = 62) reported symptoms at baseline using the FKSI, with higher scores indicating less severe symptoms. A Weibull (fully parametric) model was fit to time-to-event data to establish the relationship of baseline FKSI score with mPFS and mOS. Kaplan-Meier curves were obtained as sensitivity analyses. Results Longer progression-free and overall survivals were associated with higher (more favorable) baseline FKSI-15 and FKSI disease-related symptoms (FKSI-DRS) subscale specific to kidney cancer scores. For example, for FKSI-15 scores of 0 (most symptoms), 30, and 60 (no symptoms), the mPFS were 0.72, 3.83, and 20.43 months, respectively, and the mOS were 1.05, 6.27, and 37.53 months. Similar patterns and interpretations were observed for the FKSI-DRS scores. The results from the Kaplan-Meier analyses supported the parametric model. Discussions/conclusions Baseline patient-reported kidney cancer symptoms are linked to mPFS and mOS in a clear and interpretable way. These results support the evaluation of patient-reported symptoms at baseline in clinical trials and in clinical practice to measure symptom severity and potentially predict progression-free and overall survival outcomes. Implications for cancer survivors The results provide a heightened opportunity to use patient data not only to assist in medical treatment planning but also to prepare patients, who have advanced disease and an already reduced expected lifespan, with an opportunity to deal with the psychosocial aspects of the dying process.