Background: Local tumor ablation (LTA) and non-interventional management (NIM) emerged as alternative management options for T1a renal cell carcinoma (RCC). We investigated trends and cancer-specific mortality (CSM) after LTA and NIM, compared to partial nephrectomy (PN).
Methods: Within the Surveillance, Epidemiology, and End Results database (2004-2015), T1a RCC patients treated with PN, LTA or NIM were identified. Estimated annual proportion change methodology (EAPC), 1:1 ratio propensity score (PS) matching, cumulative incidence plots and multivariable competing risks regression models (CRR) were used to compare LTA vs. PN and NIM vs. PN. Subgroup analyses focused on patients <65 and ≥65 years.
Results: Overall 4524 patients underwent LTA vs. 1654 NIM vs. 25,435 PN. Annuals rates increased for NIM (EAPC: +3.3%, P<0.001), but not for either LTA or PN. After PS-matching in multivariable CCR, LTA (HR 1.9, P<0.001) and NIM (HR 3.0, P<0.001) showed worse 5-year CSM, relative to PN. In subgroup analyses, LTA showed no CSM disadvantage relative to PN in younger patients (HR 2.0, P=0.07). In older patients 1.64-fold CSM increase was recorded. Conversely, NIM younger (HR 3.1, P=0.001) and older (HR 3.1, P<0.001) patients exhibited higher CSM relative to PN.
Conclusions: In T1a RCC patients, NIM rates showed a modest but significant increase, while LTA and PN rates remained stable. In survival analyses, LTA exhibited higher CSM rates only for elderly patients. Conversely, NIM exhibited higher CSM rates in both younger and older patients.