Initial complete local therapy without systemic therapy versus systemic-therapy-based management in selected patients with oligometastatic renal cell carcinoma: a matched comparative study.

OBJECTIVES

To compare survival outcomes of initial complete metastasis-directed therapy (MDT) without systemic therapy (ST) and ST-based management in patients with oligometastatic renal cell carcinoma (RCC).

MATERIALS AND

METHODS

We retrospectively reviewed patients with oligometastatic RCC (≤5 lesions) treated between 2015 and 2023. Patients were categorized as MDT alone (surgery, radiotherapy, or both, without ST) or ST ± local treatment. One-to-one exact matching between the initial MDT-alone and ST-based groups was performed using six covariates (lesion count, timing of presentation, IMDC risk, Charlson comorbidity index, number of involved organs, and performance status).

RESULTS

Among 276 patients (MDT, n = 173; ST, n = 103), 72 pairs were generated after exact matching. Median follow-up was 86.2 months for the MDT and 71.6 months for the ST group in the matched cohort. MDT alone was associated with higher 5-year overall survival (OS) (73.0 % vs. 58.6 %; hazard ratio [HR] 0.45, 95 % confidence interval [CI] 0.26-0.77, p = 0.004) and cancer-specific survival (CSS) (83.7 % vs. 69.8 %; HR 0.35, 95 % CI 0.18-0.67; p = 0.001) in the matched cohort. Progression-free survival (PFS) and distant metastasis-free survival (DMFS) did not differ between groups. In the MDT alone group, the 5-year cumulative incidence of subsequent ST initiation was 48.6 %. In the whole cohort, the association was consistent across IMDC risk groups (p-interaction = 0.898).

CONCLUSIONS

In this selected post-nephrectomy cohort, an initial complete-local-therapy strategy without ST was associated with higher OS and CSS than heterogeneous, predominantly TKI-based ST management, although PFS and DMFS were similar. Given the nonrandomized treatment allocation and residual biological selection, these findings are hypothesis-generating and should not be interpreted as evidence of superiority over contemporary ICI-based therapy.