The survival outcomes of metastatic non-clear cell renal cell carcinoma in the immunotherapy era: Princess Margaret Cancer Centre (PMCC) experience.

Abstract

636 Background: Immunotherapy (IO) with or without targeted therapy (TT) is the standard treatment for patients (pts) with advanced clear cell renal cell carcinoma. The evidence to support their use in metastatic non-clear cell renal cell carcinoma (nccRCC) is based on smaller prospective trials and retrospective analyses. Here, we report the survival outcomes of pts with nccRCC treated with IO containing regimens or TT. Methods: This retrospective survival analysis was performed in metastatic nccRCC pts treated with IO and/or TT at the PMCC, Toronto between 2002 and 2021. Demographics, disease characteristics and survival outcomes were collected. Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method (log-rank). Chi-square and fisher’s exact tests were used to evaluate response rates where appropriate. Interaction between variables was estimated using Cox proportional hazards. Results: We identified 530 metastatic RCC pts, of these 69 (13%) were nccRCC treated either with an IO containing regimen or TT. Among nccRCC pts, 42 (60.9%) had papillary subtype, 10 (14.5%) chromophobe, 14 (20.3%) unclassified, and 3 (4.3%) had an XP translocation. Median age was 54 years (range: 26-75) and 48 (69.5%) were male. Overall, as per the IMDC score, 15 (21.7%), 41 (59.5%) and 13 (18.8%) pts were categorized as good, intermediate and poor risk, respectively. Median follow-up was 116 months (95%CI: 30.8-201.1 months). Pts received sunitinib (n=41), ipilimumab plus nivolumab (n=8), sorafenib (n=5), savolitinib (n=3), pembrolizumab (n=3), pazopanib (n=2), temsirolimus (n=2), pembrolizumab plus axitinib (n=1), and other TT (n=4) in the first line treatment. Everolimus (n=13), nivolumab (n=7), sunitinib (n=7), axitinib (n=2), cabozantinib (n=2), chemotherapy (n=2), pembrolizumab plus axitinib (n=1), and other TT (n=2) were given in the second line treatment. The survival outcomes and responses are shown in the table. There was no interaction between age, gender, IMDC, RCC subtypes and survival outcomes. Conclusions: While the number of pts included in our retrospective review was small, our analysis suggested that pts with metastatic nccRCC have improved survival outcomes with IO containing regimens. Validation in a prospective dataset is required before widespread clinical utilization and many trials are currently ongoing. [Table: see text]