Risk of recurrence of renal cell carcinoma in patients with locoregional disease treated surgically without adjuvant therapy: a single-center retrospective study

Abstract Background Renal cell carcinoma (RCC) ranks among ten most common cancers worldwide and novel adjuvant therapies have recently been developed. Understanding RCC recurrence patterns and their determinants becomes important for optimizing selection of patients with non-metastatic RCC who are likely to benefit from adjuvant therapy. Therefore, a retrospective study was carried out to describe demographic and clinical characteristics as well as rates of recurrence or death from any cause and disease-free survival (DFS) of Polish patients with locoregional (non-metastatic) RCC after nephrectomy classified into risk groups according to criteria established in the KEYNOTE-564 trial. Methods The study enrolled 224 patients diagnosed with locoregional (non-metastatic) RCC who underwent partial or radical nephrectomy and did not receive adjuvant therapy after the surgery. Based on the pathological tumor-node-metastasis staging, histologic grading, and presence of sarcomatoid component in the RCC, patients were classified into three risk groups: high-risk group (5 patients), intermediate to high-risk group (45 patients), and low-risk group (174 patients). Due to the low number of patients, the two former groups were merged into the intermediate to high/high-risk group. 72 patients experienced RCC recurrence or death from any cause. DFS was defined as RCC recurrence or death from any cause, whichever occurred first. The DFS analysis was carried out using the Kaplan-Meier product-limit estimator and the Cox proportional-hazard regression. Results Two factors significantly linked with the shorter DFS and higher risk of RCC recurrence or death from any cause were the intermediate to high/high-risk group (adjusted hazard ratio 2.31, CI 95%: 1.37, 3.88; p = 0.002) and the male gender (adjusted hazard ratio 1.78, CI 95%: 1.10, 2.88; p = 0.019). The estimated proportion of patients free from RCC recurrence or death from any cause in the low-risk group and intermediate to high/high-risk group was respectively: 94% (CI 95%: 86%, 97%) vs. 80% (CI 95%: 60%, 91%) after 1 year, 83% (CI 95%: 76%, 89%) vs. 63% (CI 95%: 44%, 77%) after 3 years, and 73% (CI 95%: 64%, 81%) vs. 52% (CI 95%: 32%, 68%) after 5 years. Conclusions Patients in the intermediate to high/high-risk group experience a significantly shorter period of DFS and face a 2- to 3-fold higher risk of RCC recurrence or death from any cause.