The research team prospectively collected data on all RPNs performed at Keck Medical Center. There were three inclusion criteria: patients with an enhancing tumor suspicious for cancer, large lesions (greater than 5cm) that are possible angiomyolipomas, and other factors that seem to cause hemorrhaging. The exclusion criteria were then any patients with severe cardiopulmonary or cerebrovascular disease, multiple tumors, and uncorrected coagulopathy. Once screened, the research team analyzed the comprehensive pre-operative evaluation of patients that included computed tomography imaging with critical analyses of the lesion characteristics, renal vasculature, and tumor anatomy. They additionally reviewed the pre-operative demographics such as age, estimated Glomerular Filtration Rate (eGFR), tumor size, and whether the tumor was hilar or non-hilar. The eGFR was obtained at 3 different times; immediately prior to surgery, at discharge, and from the most recent follow up at the time the study was completed. It was this most recent follow up value that was used to calculate the range in renal function. Perioperative outcomes of estimated blood loss, warm ischemia time, operative time, hospital stay, transfusion rate, margin status, and complications were recorded and analyzed for significance as well.
Of 283 patients, 45 underwent a RPN for a hilar tumor. The average tumor size for hilar tumors was, on average, 0.3cm larger than non-hilar tumors. Demographic variables did not have significance in regards to the percentage of patients with ASA classification >3, male-female ratio, and BMI. The overall complication rate was relatively low at 12.7% with the minor complication rate of Clavian grade <3 at 5.7% and the major complication rate of Clavian grades >3 at 7%.
Dr. Cacciamani concluded that RPN is a safe an efficacious procedure for hilar tumors. As the outcome profiles of hilar tumors compared similarly to the outcome profiles of non-hilar tumors, he stated that there should be no reason that complication rates of hilar tumors should be that much higher than those of non-hilar tumors despite the prevailing notion that hilar tumors have a greater degree of complexity. Dr. Cacciamani did not, however, mention how this could be due to increased preparation by surgeons for operations on hilar tumors, a very possible reason for the similar outcomes that would be a great avenue for research.
Presented by: Dr. Giovanni Cacciamani
Authors: Michael Santomauro, Sameer Chopra, Luis Medina, Charles Metcalfe, Monish Aron, Mihir Desai, Inderbir Gill, Rene Soleto, Andre Abreu, Andre Berger
Affiliation: Urology Institute, University of Southern California, Los Angeles, CA
Written by: Vinay Cooper, Department of Urology, University of California – Irvine at the 35th World Congress of Endourology – September 12-16, 2017, Vancouver, Canada