Outcomes of Consolidative Nephrectomy following Primary Immunotherapy in Advanced Renal Cell Carcinoma: A Multicenter Analysis.

ABSTRACT

BACKGROUND: To evaluate effect and outcomes of combination primary immunotherapy (IO) and nephrectomy for advanced renal cell carcinoma (RCC). METHODS: We conducted a multicenter, retrospective analysis of patients with advanced/metastatic RCC who received IO followed by nephrectomy. Primary outcome was Bifecta (negative surgical margins and no 30-day surgical complications). Secondary outcomes included progression-free survival (PFS) following surgery, reduction in tumor/thrombus size, RENAL score, and clinical/pathologic downstaging. Cox regression multivariable analysis was conducted for predictors of Bifecta and PFS. Kaplan-Meier analysis assessed PFS, comparing Bifecta and non-Bifecta groups. RESULTS: A total of 56 patients were analyzed (median age 63 years; median follow-up 22.5 months). A total of 40 (71.4%) patients were intermediate IMDC risk. Patients were treated with immunotherapy for median duration of 8.1 months. Immunotherapy resulted in reductions in tumor size (P < .001), thrombus size (P = .02), and RENAL score (P < .001); 38 (67.9%) patients were clinically downstaged on imaging (P < .001) and 25 (44.6%) patients were pathologically downstaged following surgery (P < .001). Bifecta was achieved in 38 (67.9%) patients. Predictors for bifecta achievement included decreasing tumor size (HR 1.08, P = .043) and pathological downstaging (HR 2.13, P = .047). Bifecta (HR 5.65, P = .009), pathologic downstaging (HR 5.15, P = .02), and increasing reduction in tumor size (HR 1.2, P = .007) were associated with improved PFS. Bifecta patients demonstrated improved 2-year PFS (84% vs. 71%, P = .019). CONCLUSIONS: Primary immunotherapy reduced tumor/thrombus size and complexity. Pathologically downstaged patients were more likely to achieve bifecta, and these patients displayed improved 2-year PFS. Our study supports further inquiry in the use of CRN following primary immunotherapy for advanced renal cancer.