A Multicentered, Propensity Matched Analysis Comparing Laparoscopic and Open Surgery for pT3a Renal Cell Carcinoma: Expert Commentary

Laparoscopic renal surgery (LRS) has long been recognized for its improvements over open renal surgery for patient quality of life. However, LRS efficiency in terms of oncology and recurrences has yet to be compared. This team attempted to do just that by contrasting ORS and LRS on patients with Pathologic T3a (pT3a).

Pathological T3a renal disease has an advanced disease stage and is typically aggressive with  5-year disease-free survival rates ranging from 30% to 85%. Using a propensity-matched approach, the authors attempted to compare oncologic outcomes between LRS and ORS in the treatment of pT3a Renal Cell Carcinoma (RCC) by using a large, multi-centered collaborative effort.

This study utilized the Canadian Kidney Cancer Information System to create propensity scores matching for age, gender, tumor size, grade, histology, and surgical approach for 3638 patients. The Canadian Kidney Cancer Information System is a prospectively maintained database for patients diagnosed with RCC from 15 Canadian hospitals. Due to the CKCIS being prospectively maintained, the researchers were unable to fully randomize the surgeries as the choice of the procedure was dependent on the preferences of the patient and the surgeon. The only exclusion criterion was metastatic disease for the palpable jump in randomness and variability. Of the 3638 patients, 501 were found to have pT3a disease and were free of nodal or metastatic disease at the time of surgery. 226 of these 501 underwent LRS and 275 underwent ORS. Propensity matching was chosen as it permits the comparison of outcomes in patients who are similar on all measured baseline characteristics and so easily minimized bias.

After follow up of both groups, the researchers found no difference in overall survival between ORS and LRS. They included a combination of radical and partial nephrectomy patients in the analysis to determine whether those make a significant difference but these simply confirmed the overall findings. However, those that underwent partial nephrectomies were more likely to have a favorable clinical stage but had an adverse final surgical pathology. Additionally, there appeared to be a higher rate of positive surgical margins in the ORS group (7% to 13%) though this would have to be more fully analyzed in another study. 

This study represents the largest comparative evaluation of patients undergoing LRS and ORS for pT3a disease in literature. It confirms the findings of other studies about laparoscopic surgery appearing superior to open in terms of patient quality of life and recovery times, and blood loss as well as the fact that laparoscopic surgery is safe for the treatment of pT3a disease. It very thoroughly analyzed previous literature on LRS and ORS and even described the differences and similarities between those and this one. The method of propensity-matched scoring seemed to vastly increase the accuracy of the study and should be a great baseline for further studies analyzing other surgeries and oncological outcomes. The average follow-up was low, however, as most diseases do not recur within 2 years and so much of the data could be insignificant and wrong. If they followed up for at least 5 years, then they would have a much stronger conclusion and a more valid study. Overall, this was an excellently written and analyzed paper with a scientifically backed conclusion with the data they had.

Written by: Zhamshid Okhunov, MD Department of Urology, University of California, Irvine Urology

Read the abstract 
email news signup