AUA guideline tackles small renal mass controversy

August 1, 2009

AUA has addressed a number of questions and controversies concerning small renal masses in a new clinical guideline reflecting current research. Steven C. Campbell, MD, PhD, guideline co-chair, discusses the rationale for the guideline and key recommendations.

Q: Please describe the process for developing the guideline on small renal masses.

A thorough meta-analysis was performed and, through a variety of meetings and conference calls, the panel reached consensus about the different modalities and the appropriate treatments for patients with clinical T1 renal masses. Major limitations of the literature included a paucity of comparative studies, strong selection biases, and limited length of follow-up for many of the newer modalities.

A: One of the main reasons this panel was commissioned was that management of the small renal mass has become controversial and, to some extent, current practices are inconsistent with what the literature will support. In particular, we now recognize that these masses are very heterogeneous: 20% are benign and only about 20% to 25% exhibit potentially aggressive features.

One of the very strong statements that the panel makes is strong consensus in favor of nephron-sparing approaches for the management of clinical T1 renal masses; that is, partial nephrectomy, thermal ablation, or observation, depending upon the clinical circumstances. Radical nephrectomy is still occasionally required, based on tumor size and location, but should only be performed when necessary.

Q: Do you think all practicing urologists should treat small renal masses?

A: It's become a very common clinical scenario. There are probably 30,000 to 40,000 new cases of clinical T1 renal masses annually. We're seeing patients with these masses in all of our practices, so we need to be cognizant of the issues surrounding their management.

It's important for every practicing urologist to assess his or her own skill level and expertise and try to determine the appropriate management approach for a given patient. Some patients will require partial nephrectomy or thermal ablation, for example, and individual urologists need to decide whether they're comfortable managing or they might consider referral. It has to be decided on an individual basis.

Q: How does experience in laparoscopy and robotics fit in?

The panel not only looked at oncologic outcomes and renal functional outcomes, but also morbidity, and we came out strongly in favor of minimizing morbidity with minimally invasive approaches whenever possible.

We looked specifically at the urologic morbidity associated with laparoscopic partial nephrectomy versus open partial nephrectomy. In general, laparoscopic partial nephrectomy tended to have increased urologic morbidity, whether it was urinary leak or postoperative hemorrhage. The morbidity with laparoscopic partial nephrectomy was somewhat higher than with open partial nephrectomy and, in general, we had consensus that for the most complex cases of partial nephrectomy, such as a solitary kidney, an open approach would probably be safer for most practitioners.