NARUS 2019: Comparison of Outcomes Between Minimally Invasive and Open Nephrectomy Across a Health Care System

Las Vegas, Nevada (UroToday.com) Dr. James Porter presented data comparing outcomes between minimally invasive and open nephrectomy across a large health care system.

Partial nephrectomy preserves eGFR better than radical nephrectomy, but in the US it is still underutilized, probably due to the more technical challenges posed by this procedure compared to radical nephrectomy.

Minimally invasive techniques for partial nephrectomy (laparoscopic and robotic) result in reduced morbidity, shorter length of stay, and is more expensive when compared to open nephrectomy.

Using the Providence health care system, which is a multicenter collaboration of hospitals across 6 US states, Dr. Porter and his team reviewed the utilization and cost of nephrectomies across all centers. The Providence St. Joseph Robotics is the 2nd largest health care system in the US, comprising of 51 hospitals, 53 robots, and 120 million dollars invested in robotic surgery. Dr. Porter serves as the director of robotic surgery in this healthcare system.

The goals of the review conducted by Dr. Porter included:
  1. Utilization of partial vs. radical nephrectomy, open vs. minimally invasive
  2. Cost comparison
  3. Outcomes
The data analysis was performed using the EPIC database, and complications, readmissions were assessed as well. The analysis included all procedures done between 2013-2015, with 141 surgeons at 21 hospitals and 28 robots. A total of 1693 procedures were analyzed. Direct cost and indirect cost were analyzed as well. Direct cost included OR time, anesthesia, PACU time, supplies and length of stay. Indirect cost included staff salaries, service contracts, and robotic depreciation. Depreciation is an accounting principle applied to capital equipment with a limited life. It is usually done as a straight line depreciation. Depending on how it is calculated, it can make the robot appear costly.

When comparing length of stay and OR time, robotic partial was 2.06 days compared to 5.27 days for open partial. However, the OR time was longer for the robotic partial (203 min vs. 147 min), p<0.01). Readmission and complications were significantly lower in the robotic partial group, compared to other surgical options. Data also demonstrated that patients of surgeons with low experience have a higher length of stay than that of patients of surgeons with a high-volume experience. The same comparison results weres seen with transfusion rates, complications, and readmission rates.

Next, Dr. Porter assessed the cost comparison, demonstrating that robotic radical nephrectomy was the most expensive procedure.

The study had several limitations including its retrospective design and the fact that it was limited to the Providence hospitals. In conclusion, radical nephrectomy is more common even for small renal masses. Robotic partial nephrectomy has the shortest length of stay, lowest readmission rates, and fewest complications. Minimally invasive techniques cost more than open procedures, and lastly, low volume surgeons are more likely to treat patients that have a longer length of stay, a higher rate of complications and transfusions.


Presented by: James Porter, MD, laparoscopic surgeon, Swedish Urology Group, Seattle, Washington

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at  2019 3rd Annual North American Robotic Urology Symposium (NARUS), February 8-9, 2018 - Las Vegas, Nevada, United States