The following is a summary of “No difference in renal function outcomes for patients with oncocytoma managed with active surveillance vs. partial nephrectomy,” published in the March 2023 issue of Urologic Oncology by Ginsburg et al.
The objective is to compare the renal function outcomes between patients diagnosed with oncocytomas who undergo active surveillance (AS) and those who undergo partial nephrectomy (PN). Our medical team thoroughly examined our institutional database to identify patients who had undergone biopsy or surgical procedures and were diagnosed with oncocytoma between 2000 and 2020. The principal objective was to evaluate disparities in renal function outcomes among individuals receiving AS versus PN. Two generalized estimating equations (GEE) were utilized, incorporating an interaction term between follow-up duration and management strategy, to forecast the average estimated glomerular filtration rate (eGFR) for patients managed with active surveillance (AS) and partial nephrectomy (PN) as well as the likelihood of advancing to stage III or higher chronic kidney disease (CKD).
About 114 eligible patients were identified, of which 32 were subjected to AS management. The median follow-up duration for patients who underwent partial nephrectomy (PN) was 21 months, while those who underwent active surveillance (AS) had a median follow-up duration of 44 months. The AS cohort exhibited a higher median age of 72 years than the PN cohort, with a median age of 65 (P<0.001). Additionally, the AS group demonstrated a lower baseline renal function with a median estimated glomerular filtration rate (eGFR) of 71 mL/min/1.73m2 in contrast to the PN group with a median eGFR of 82 mL/min/1.73m2 (P<0.001). The renal mass size from the baseline imaging was comparable between patients who underwent partial nephrectomy (PN) and active surveillance (AS), with a mean of 2.8 cm and 2.9 cm, respectively. The P-value was calculated to be 0.634.
The study found no statistically significant difference in the predicted longitudinal estimated glomerular filtration rate (eGFR) and the predicted probability of progression to stage III or greater chronic kidney disease (CKD) between patients undergoing percutaneous nephrolithotomy (PN) and those undergoing active surveillance (AS). The results showed a mean difference of -0.079 in eGFR with a 95% CI of -0.18-0.023 and a P=0.129. The odds ratio for progression to CKD stage III or greater was 0.61, with a 95% CI of 0.16-2.33 and a P=0.47. The renal function outcomes of patients who underwent AS or PN with an oncocytoma were similar in our institutional dataset. Based on comparable renal function outcomes observed in individuals undergoing AS and PN, surgical intervention should be reserved for specific patients diagnosed with oncocytomas.