Impact of systemic therapy (ST) on deferred cytoreductive nephrectomy (CN) perioperative outcomes: A National Surgical Quality Improvement Program (NSQIP) analysis.

650 Background: Management of metastatic renal cell carcinoma (mRCC) is highly individualized and often involves cytoreductive nephrectomy (CN) and systemic therapy (ST). The optimal sequencing of CN and ST is uncertain. A difference in perioperative outcomes based on sequence of CN and ST could influence decision-making. We conducted this NSQIP analysis to assess whether preoperative systemic therapy adversely impacted perioperative outcomes in patients receiving deferred CN. Methods: This analysis was conducted using the American College of Surgeons NSQIP Participant Use Data File for years 2019 and 2020. These years were selected because data on receipt of preoperative therapy is only available since 2019. Inclusion criteria were i) CPT code consistent with nephrectomy, ii) urologist operating surgeon & iii) presence of disseminated cancer. All cases with ICD-10 diagnosis codes not consistent with mRCC were excluded. Groups were stratified by their receipt of preoperative systemic therapy within 90 days before CN and we assessed 46 preoperative and perioperative outcomes. Results: The study cohort included 505 patients with 115 (23%) who received preoperative ST. No differences were noted in perioperative outcomes (Table). Patients receiving preoperative ST were more likely to be on steroids (23% vs. 7%, p<0.01) and develop urinary tract infections (4.3% vs. 0.5%, p<0.01). There were no significant differences noted in other related variables like surgical site infections, wound dehiscence, sepsis, septic shock, pneumonia, cardiovascular complications, preoperative hypertension, or preoperative diabetes (p>0.05). Conclusions: Because preoperative ST did not have an appreciable impact on deferred CN perioperative outcomes, decision making for ST and CN sequencing should not be influenced by perioperative outcomes. Those who undergo deferred CN are unlikely to experience delayed time to surgery or perioperative complications from their ST. [Table: see text]