Primary tumor ablation in metastatic renal cell carcinoma

The role of primary tumor ablation (pTA) in metastatic renal cell carcinoma (mRCC) is unknown. We compared pTA-treated mRCC patients to patients who underwent no local treatment (NLT), as well as patients who underwent cytoreductive nephrectomy (CN).

Within the Surveillance, Epidemiology, and End Results database (SEER, 2004-2020), we identified mRCC patients who underwent either pTA, NLT or CN. Endpoints consisted of overall survival (OM) and other-cause mortality (OCM). Propensity score 1:1 matching (PSM), multivariable cox regression models (OM), as well as, multivariable competing risk regressions (CRR) models (OCM) were used.

We identified 27,087 mRCC patients, of whom 82 (0.3%) underwent pTA, 17,266 (64%) NLT and 9,739 (36%) CN. In comparisons of pTA vs. NLT mRCC patients addressing OM, after 1:1 PSM, median survival was 19 months for pTA vs. 4 months for NLT patients (multivariable HR 0.3, 95% CI 0.22-0.47, P < 0.001). No statistically significant OCM differences were recorded in multivariable CRR (HR 1.13 95%, CI 0.52-2.44, P = 0.8). In comparisons of pTA vs. CN, after 1:1 PSM, no statistically significant differences in OM (HR 1.22, 95% CI 0.81-1.83, P = 0.32), as well as OCM (HR 1.4, 95% CI 0.56-3.48, P = 0.5) were recorded.

In mRCC patients, pTA is associated with significantly lower mortality compared to NLT. Interestingly, OM rates between pTA and CN mRCC patients do not exhibit statistically significant differences. This preliminary report may suggest that pTA may provide a comparable survival benefit to CN in highly selected mRCC patients.