Upfront versus deferred cytoreductive nephrectomy following targeted or immunotherapy: a population-based propensity score-matched analysis of perioperative complications

Purpose: To evaluate the incidence of postoperative complications after cytoreductive nephrectomy (CN) following first-line treatment for metastatic renal cell carcinoma (mRCC), and to compare it with postoperative complications of upfront CN. Methods: For this population-based retrospective study, the PearlDiver Mariner database (PearlDiver Technologies, Colorado Springs, CO), a database of insurance billing records was analyzed. Using relevant ICD-9/10 and CPT codes, patients diagnosed with mRCC between 2011 and 2021, who received first-line systemic molecular therapy (SMT), either tyrosine kinase inhibitors (TKI) or immune-checkpoint inhibitors (ICI), were identified. The selected population was stratified into two cohorts according to the timing of CN (deferred: after SMT vs. upfront: before SMT). Propensity-score matching (PSM) was performed as per baseline patients' characteristics to control for potential confounders between the two cohorts. The primary outcome was to compare 30-day postoperative complications rate between patients undergoing upfront vs. deferred CN. Results: After PSM, 162 patients who received upfront CN were compared with 162 patients who underwent deferred CN. The overall rate of 30-day postoperative complications was statistically significantly higher in patients undergoing deferred CN (33.9%), compared to patients treated with upfront CN (21%, p < 0.01). In addition, the rate of both medical (26.5% vs. 14.2%, p < 0.01) and surgical (14.8 vs. 7.4%, p = 0.03) complication rate was statistically significantly higher in deferred vs. upfront CN. Multivariable logistic regression analysis revealed that none of the treatment regimens significantly predicted the occurrence of postoperative complications. Conclusion: Patients undergoing deferred CN experience a higher rates of overall, medical, and surgical 30-day postoperative complications compared to those receiving upfront surgery. Findings from this study should be interpreted within the limitations of this type of analysis.