First-Line Immune Combination Therapies for Nonclear Cell Versus Clear Cell Metastatic Renal Cell Carcinoma: Real-World Multicenter Data From Germany

Abstract

IntroductionThe aim was to compare treatment outcomes of clear cell metastatic renal cell carcinoma (ccmRCC) versus non-ccmRCC (nccmRCC) patients who received first-line immune combination therapies. Materials and MethodsWithin our retrospective multi-institutional consecutive database of eight tertiary-care centers, we identified mRCC patients treated with first-line immune combination therapies between 11/2017 and 12/2022. Using log-rank analysis and multivariable Cox regression, we tested for differences in overall survival (OS) and progression-free survival (PFS) of nccmRCC versus ccmRCC patients. Covariables consisted of age at diagnosis, sex, International Metastatic Renal Cell Carcinoma Database Consortium risk groups, Eastern Cooperative Oncology Group status, and sarcomatoid feature. ResultsOf 289 study patients, 39 (13%) patients harbored nccmRCC. Median OS was 37 months versus not reached for ccmRCC versus nccmRCC patients (P = .6). Median PFS was 13 versus15 months (P = .9). Multivariable Cox regression models did not identify nccmRCC as an independent predictor of higher overall mortality in mRCC patients (hazard ratio [HR]: 1.23; P = .6) or a higher progression rate (HR: 1.0; P = 1.0). ConclusionIn our real-world multi-institutional study, no differences between ccmRCC and nccmRCC patients receiving first-line immune combination treatment were observed, even after adjustment for important patient and tumor characteristics. More prospective trials in nccmRCC patients are needed.