Post-Metastasectomy Adjuvant Therapy in Patients with Renal Cell Carcinoma: A Systematic Review.

Background: Pembrolizumab is established as adjuvant therapy for patients with high-risk clear cell renal cell carcinoma (ccRCC) after resection. Patients with completely resected metastatic disease (M1 NED) seem to have greater benefit from adjuvant pembrolizumab in both disease-free survival (DFS) and overall survival (OS); yet, with other agents, adjuvant therapy has not been shown to improve survival. As newer therapies evolve, it is important to understand the efficacy of systemic agents in this patient population.

Objective: We aimed to systematically review available trials investigating adjuvant therapy after metastasectomy in RCC.

Methods: Following PRISMA guidelines, we performed a systematic literature search using PubMed and Embase through January 2024. For inclusion, studies were required to include completely resected patients with known metastatic RCC. Patients with only locally advanced and/or regional nodal involvement (N1) alone were excluded. Titles and abstracts were screened to identify articles for full-text, and then a descriptive review was performed.

Results: A total of 149 articles were initially identified. Ultimately 9 articles published before the end of January 2024 met our inclusion criteria and were included in the analysis. Data were extracted and organized to reflect the role of adjuvant treatment - both targeted therapies as well as immunotherapy in patients who had undergone metastasectomy and rendered M1 NED. With the exception of pembrolizumab, adjuvant therapy in M1 NED was not found to be associated with improved survival.

Conclusions: Pembrolizumab appears to benefit M1 NED ccRCC patients after resection even more than other high-risk ccRCC patients. Yet, this same benefit has not been seen with other agents. Future research should focus on trying to establish which M1 NED patients benefit from adjuvant treatment.