A multi-centre review of the use of adjuvant pembrolizumab for renal cell carcinoma.

Abstract

484 Background: In patients with increased risk of recurrence after surgical resection of renal cell carcinoma (RCC), adjuvant treatment with pembrolizumab has been shown to reduce recurrences and improve overall survival. This treatment is now offered as standard of care in England. In the KEYNOTE 564 trial 96.3% of patients who received pembrolizumab experienced at least one adverse event and 32.4% of patients experienced an adverse event of grade 3-5. 38.9% of trial patients discontinued treatment early; 21.3% due to adverse events and 10.5% due to disease recurrence. 7.4% of patients who were treated with pembrolizumab were treated with high dose systemic steroids (≥40mg prednisolone per day). Aims: To evaluate how real world data compares to the findings of KEYNOTE 564, in UK centres. Methods: This was a retrospective review of 182 patients treated with adjuvant pembrolizumab following surgery for RCC across 7 centres in the UK between 2022-2024. Toxicity, discontinuation, use of steroids, and recurrences were assessed. Results: 182 patients were started on adjuvant pembrolizumabbetween 2022-2024. Median FU is 8.4 months. Overall, 18 patients (9.9%) have experienced recurrence, and 15 (83.3%) of these occurred during treatment. 82 (45.1%) patients are currently undergoing treatment, and 41 (22.5%) patients completed the full 12-month course. 59 (32.4%) patients did not complete the full course, 44 (24.1%) due to toxicity and 15 (8.2%) due to recurrence. Mean number of cycles completed for patients discontinuing treatment was 3.4 (range 1 – 8). Toxicity was varied with endocrine (24%), skin (23%) & colitis (12%) being the most common toxicities of all grades. 24 (13.2%) and 3 (1.6%) patients experienced grade 3 and grade 4 toxicities respectively. The commonest toxicity leading to treatment discontinuation was colitis (27.3%). The number of patients requiring steroids for toxicity management was 59 (32.4%) with 34 (18.6%) requiring high dose steroids and 7 (3.8%) requiring additional immunosuppressive agents (methotrexate (3), infliximab (3) and MMF (1)). 26 (14.2%) patients required hospitalisation for management of toxicity. There was 1 treatment-related death due to complications from colitis and nephritis. Conclusions: In our group of patients, discontinuations of Pembrolizumab due to toxicity and recurrence rates were similar to data from KEYNOTE 564. A larger proportion of patients in our real world data were treated with high dose steroids (19%) compared to the trial (7.4%).