Clinical Outcomes of Robotic Assisted Partial Nephrectomy for Pathologic T3a Renal Masses With Venous Tumor Thrombus

Objective: To evaluate the safety, efficacy, and early oncologic outcomes of pathologic T3a (pT3a) renal cell carcinoma with venous involvement treated with robotic partial nephrectomy (RPN), given that experience and outcomes in this group is limited. Methods: A retrospective chart review of patients undergoing RPN from September 2009 to July 2020 was performed. Outcomes were captured from patients with pT3a disease with vein involvement. Clinical characteristics were analyzed using SPSS (IBM, Armonk, NY). Local recurrence-free survival and metastasis-free survival at 2 years were calculated from Kaplan-Meier survival curves. Results: For 45 included patients, mean operative and warm ischemia times were 199.6 ± 47.3 minutes and 30.5 ± 10.5 minutes, with mean estimated blood loss of 324.9 ± 209.5 cc. Rates of transfusion, embolization, re-admission, and re-operation at 30 days were 8.9% (4/45), 2.2% (1/45), 11.1% (5/45), and 6.7% (3/45; cystoscopic stent placement), respectively. All tumors were malignant on pathology, with clear cell renal cell carcinoma being the most common (91.0%, n = 41). The positive margin rate was 6.7% (n = 3). Local recurrence occurred in 4.4% (n = 2) at a mean time of 5.2 ± 2.3 months. Four patients (8.9%) progressed to metastatic disease at a mean of 22.2 ± 23.0 months. At 2 years, local recurrence-free survival was 95.4% and metastasis-free survival was 95.3%. Conclusion: We present the largest known series of patients RPN for pT3a renal masses with venous tumor involvement. We found it both feasible and safe in the appropriate hands. Short term oncologic outcomes for these patients appear more favorable than historic literature suggested.