Turning the tide: pembrolizumab's triumph in adjuvant RCC therapy

In recent years, kidney cancer has shown an increased worldwide incidence of more than 400 000 novel cases annually. Although more than half of patients are diagnosed at a localised stage, this disease presents a high-risk of relapse after surgery. Thus, there is a need for adjuvant therapy post-resection to reduce cancer recurrence and prolong disease-free and overall survival. Thorough investigation of adjuvant drugs for renal cell carcinoma (RCC) has shown little promise in the last fifty years, with no recorded overall survival benefits. This was the case until pembrolizumab, an immune checkpoint inhibitor, was introduced into the adjuvant RCC space through the KEYNOTE-564 trial. The adjuvant administration of this novel anti-PD-1 drug demonstrated a significant overall survival benefit which has led to an update in the current treatment guidelines of RCC. This substantial change in the standard of care also caused an investigation of possible treatment combinations and an adoption of innovative predictive biomarkers. In this review, we will present the evolution of past adjuvant ICI trials for the treatment of RCC, the implications of pembrolizumab's overall survival benefits and a discussion of future directions concerning new RCC drug trials and liquid biopsy-based biomarkers.