In this abstract by the Michigan Urological Surgery Improvement Collaborative (MUSIC), which is a large multi-institutional data sharing program among Michigan urology programs in an effort to improve statewide urologic care – it is a unique program that provides great insight into a large mixed practice community. Previously focused on prostate cancer primarily, they have now expanded to other fields, including kidney (focusing on masses <= 7cm, cT1 lesions) and stones.
This is a pilot study of the MUSIC-KIDNEY program to assess utilization of RTB in newly diagnosed cT1 renal lesions within this large Michigan Urology community. Data collection started in September 2017 at 8 practices; data is input by designated paid abstractors. Data was input for all patients at a single time point 3 months (120 days) after the initial presentation – an allowance for one additional data extraction 3 months later was allowed if a final treatment plan had not been made yet. Management was separated as AS, RTB, or active treatment, as well as details regarding the follow-up plan.
581 patients with renal masses ≤7cm were identified and included, and of these, only 71 (12.2%) underwent a RTB.
At an institutional level, as with prostate cancer management, there was significant variability - RTB utilization across the 8 sites ranged from 0-23% (median 11%), with 11% of RTB performed by a urologist.
When comparing patients who did or did not have an RTB, no statistical differences in patient and tumor characteristics were observed between those having or not having RMB (Table 1 below):
- 60% of RTB were performed for masses 1-3 cm; None for mass < 1 cm
- 97% of the RTB procedures were same-day procedure, with discharge home after the procedure
As for complication, 2 patients (2.8%) were evaluated in the emergency department (with 1 hospitalization) following RTB.
With regards to RTB outcomes, the non-diagnostic rate of RMB across the collaborative was only 5.6% (n=4); the remaining RTB were categorized as benign (n=16, 22.5%), favor malignancy (n=4, 5.6%), or malignant (n=47, 66.2%). This nondiagnostic rate is significantly lower than other series, even at centers of excellence.
Patients with a benign biopsy were more likely to be surveilled then patients managed without RTB (81% vs 48%, p=0.009) – which makes sense, as there is now pathology suggesting a benign tumor. The benign histology rate at surgery in RTB naïve patients was 13.1% vs 3.03% with RTB (p=0.09) – these represent the patients that could have been spared surgery if they had been biopsied ahead of time. Importantly, 15 patients (25%) with malignancy at RMB were still surveilled – as greater knowledge of the indolent natural history of RCC becomes known, AS may become a more utilized approach for small RCCs with a low grade.
The full breakdown of RTB utilization, pathology outcomes, and management is seen below:
- 4-13% of patients undergoing treatment, regardless of prior RTB, had benign final pathology
- 201 cT1 and 40 cT1b masses without RTB were put on AS – which is a great sign that AS is increasingly being utilized
Presented by: Anita K. Patel, MD, Internal Medicine, Nephrology, Transplant Surgery, Henry Ford Hospital, Detroit, Michigan, United States
Written by: Thenappan Chandrasekar, MD (Clinical Instructor, Thomas Jefferson University) (twitter: @tchandra_uromd, @JEFFUrology) at the 34th European Association of Urology (EAU 2019) #EAU19, conference in Barcelona, Spain, March 15-19, 2019.