(UroToday.com) Dr. Cameron Britton shared an interesting presentation on local recurrence rates after partial nephrectomy. It is believed that true local recurrence following partial nephrectomy is experienced in 1-3%, making it highly uncommon. Since the nature of this phenomenon has been variably defined in previous studies, Britton’s team sought out to investigate this point of view. Specifically, they sought to 1) create a risk score based on preoperative variables to predict local recurrence postoperatively, 2) determine predictors of true local recurrence, and lastly 3) determine if there is an association between recurrence with distant metastasis and cancer-specific survival after partial nephrectomy.
From 2000-2020, 2,164 patients that were treated for unilateral, sporadic, localized (MO) renal cell carcinoma were enrolled into the study. For this study, local recurrence was defined as new enhancing tumor(s) grown within the area of partial nephrectomy confirmed by cross sectional imaging (CT or MRI). Using the Kaplan-Meier method, patient survival rates were calculated; the Cox proportional hazards regression models were used to associate death with renal cell carcinoma after partial nephrectomy.
The preoperative factors determined were: 1) age >60, 2) patients with solitary kidney, 3) patients that were symptomatic at time of presentation, 4) stage of cT and 5) open surgical approach. Furthermore, the postoperative factors were: 1) positive margins, 2) pT stage, 3) histologic type of renal cell carcinoma (clear vs non-clear cell), and 4) increase of tumor size (cm).
The image below depicts hazard ratios for the preoperative factors used to create a risk score and the points associated for patient counseling.
The study yielded 106 cases of true local recurrence (4.89%). The data showed that local recurrence median time was 3.3 years and at 10 years, the number of local recurrences was at 6%. Refer to the image below for the recurrence free rates after partial nephrectomy.
The image below depicts local recurrence association at different years in accordance with the risk scores created from preoperative factors.
The image below depicts the multivariable associations of parameters associated with true local recurrence after partial nephrectomy for clear cell renal cell carcinoma.
The results show that pT stage, clear cell history and positive margins were all predictors of local recurrence. All five of the preoperative factors predicted local recurrence. In respect to management, 52 (49.1%) of patients received ablation and 32 (30.2%) underwent complete radical nephrectomy. A total of 45 patients died during the study (median 3.5 years) with 26 dying from renal cell carcinoma at a median time of 1.9 years. 83 patients had no change (remaining at M0) while 26 subsequently developed distant metastases at a median of 1.5 years.
When analyzed as time-dependent, local recurrence proved to be associated with cancer specific death (p<0.001) and when adjusting for distant metastasis (p=0.03). Britton emphasized that with recurrence happening nearly 5 years, there is a need for more aggressive long-term surveillance. Furthermore, he suggested that interventions should be taken into account to prevent deaths due to the association between renal cell carcinoma and true local recurrence. Lastly, Britton stated that the implementation of a risk scare can be a useful preoperative tool to help guide patients into the proper intervention they require.
A member of the audience asked if there was a standard imaging required for analysis of each patient case. Dr. Britton said that more than 90% of patients had CT’s however not all were able to rely on CT for imaging thus the addition of those who had MRI’s. Dr. Thompson of Mayo Clinic (serving as a moderator) also confirmed this statement and referred to the findings of Dr. Suzanne B. Stewart-Merrill who showed that even after 5 years, imaging helps find recurrences within patients. Lastly, one more member of the audiences asked for the predictors of negative margins that occurred within patients. Dr. Britton clarified by that these factors were clear cell histology and pT stage.
Presented by: Cameron J. Britton, MD, Mayo Clinic, @MayoUrology on Twitter
Written by: Seyed Amiryaghoub M. Lavasani, B.A., University of California, Irvine, @amirlavasani_ on Twitter during the 2023 American Urological Association (AUA) Annual Meeting, Chicago, IL, April 27 – May 1, 2023
References:
- Kay FU, Pedrosa I. Imaging of Solid Renal Masses.Urol Clin North Am. 2018 Aug;45(3):311-330.
- Welch HG, Skinner JS, Schroeck FR, et al: Regional variation of computed tomographic imaging in the United States and the risk of nephrectomy. JAMA Intern Med 178:221-227, 2018.
- Wood EL, Adibi M, Qiao W, et al:. Local Tumor Bed Recurrence Following Partial Nephrectomy in Patients with Small Renal Masses. J Urol. 2018 Feb;199(2):393-400.