Integrating On-Treatment Modified Glasgow Prognostic Score and Imaging to Predict Response and Outcomes in Metastatic Renal Cell Carcinoma

Importance In the era of immuno-oncology, imaging alone seems to be insufficient to capture treatment responses, as patients with stable disease treated with immunotherapy have a wide range of clinical outcomes. There is an unmet need for complementary (ideally cost-efficient) markers that enable assessment of therapy response and outcomes in conjunction with imaging. Objectives To examine whether longitudinal changes in the modified Glasgow prognostic score (mGPS), which is based on C-reactive protein and albumin, can predict responses and outcomes in patients with metastatic renal cell carcinoma (mRCC). Design, Setting, and Participants This post hoc analysis, conducted from October 2022 to April 2023, evaluated the prognostic and predictive performance of on-treatment mGPS in patients with mRCC being treated with atezolizumab (plus bevacizumab) or sunitinib in 2 randomized clinical trials: the phase 3 IMmotion151 study (discovery cohort) and the phase 2 IMmotion150 study (validation cohort). Main Outcomes and Measures Outcomes were investigator-assessed progression-free survival (PFS) per Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1 and overall survival (OS) for survival analyses. To compare the prognostic value of the on-treatment mGPS with radiologic staging, we used RECIST assessed by the Independent Review Committee (IRC-RECIST) to ensure high data quality. Results Of the 915 patients with mRCC in the IMmotion151 discovery cohort, baseline mGPS was available for 861 patients and on-treatment mGPS for 691. The IMmotion150 validation cohort included 305 patients with mRCC, and on-treatment mGPS could be evaluated for 199. In the IMmotion150 study, on-treatment mGPS predicted outcomes as early as 6 weeks following therapy initiation, thereby opening a window for early therapy adjustments. In both clinical trials, on-treatment mGPS provided valuable prognostic information regardless of imaging-assessed treatment response at first staging. Of note, in the disease control subgroup, on-treatment mGPS exhibited superior and independent prognostic information compared with IRC-RECIST (available for 611 patients; C-index, 0.651 [95% CI, 0.588-0.714] for the mGPS during treatment vs 0.574 [95% CI, 0.528-0.619] for IRC-RECIST). Conclusions and Relevance These data support the concept of integrating on-treatment mGPS for more holistic and patient-centered therapy monitoring in addition to radiologic staging to improve clinical care at a low cost for patients with mRCC.