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.