New AUA Guidelines Call for Nephron-sparing Procedures for Renal Tumors When Possible
July 15, 2009
CHICAGO-The American Urological Association (AUA) is changing its guidelines for the management of early-stage renal masses. It says full kidney removal is not always the best treatment for small renal tumors and could lead to chronic kidney disease and increased risk of cardiovascular disease. Nephron-sparing treatments, such as partial nephrectomy, thermal ablation, and active surveillance, minimize these risks and are viable options for patients with early stage (T1a) kidney tumors, according to new clinical guidelines issued by the AUA at its 104th annual meeting.
Currently, kidney cancer is the most lethal of the commonly diagnosed urologic cancers. Detection of clinical stage I (<7.0 cm) renal masses has increased in frequency, with more than 50,000 people diagnosed annually. It was previously believed that all kidney tumors, regardless of size or aggressiveness, were best managed by radical nephrectomy. increased strain on the remaining kidney, however, can lead to chronic kidney disease and predispose patients to certain metabolic complications, including an increased risk of cardiovascular events. Nephron-sparing approaches can minimize morbidity and provide effective cancer control.
"These are the first guidelines for the management of kidney cancer that have been commissioned by the AUA, and these guidelines are specifically focused on early-stage kidney cancer," said Steven Campbell, MD, PhD, professor of surgery, Center for Urologic Oncology, Cleveland Clinic, Cleveland, Ohio. "Clinical stage T1 kidney cancers are being found with increased incidence and are now a relatively common clinical scenario. We used to think they were all malignant, but now we have learned that they are very heterogeneous, 20% benign and only about 20% exhibiting potentially aggressive features."
In developing these new guidelines, the panel assessed the efficacy of the current major treatment approaches.
Nephron-sparing and radiation nephrectomy. The panel concluded that nephron-sparing surgery should be considered for all patients with a clinical T1 renal mass, presuming adequate oncologic control can be achieved. Radical nephrectomy is still a viable option when necessary based on tumor size, location, or radiographic appearance if nephron-sparing surgery is deemed unadvisable. A laparoscopic approach to radical nephrectomy is now an established standard, because it is associated with a more rapid recovery than an open approach.
Partial nephrectomy. Surgical excision by partial nephrectomy is a reference standard for the management of clinical T1 renal masses, whether for imperative or elective indications, given the importance of renal function and avoidance of chronic kidney disease. In general, open partial nephrectomy is preferred for complex cases.
Thermal ablation. Thermal ablation (cryoablation or radiofrequency ablation), performed either percutaneously or laparoscopically, is a treatment option for a patient at high surgical risk who wants active treatment and accepts the need for long-term surveillance. Counseling about thermal ablation should include a balanced discussion of the increased risk of local recurrence when compared with surgical excision, the potential need for re-intervention, the lack of well-proven radiographic parameters for success, the potential for difficult surgical salvage if tumor progression is found, and the substantial limitations of the current thermal ablation literature. Larger tumors (>3.5 cm) and those with irregular shape or infiltrative appearance may be associated with an increased risk of recurrence when managed with thermal ablation.
Active surveillance. Active surveillance is a reasonable option for the management of localized renal masses that should be discussed with all patients and should be a primary consideration for patients with decreased life expectancy or extensive comorbidities that would increase the risks of intervention. More aggressive or larger tumors (>3 cm), however, should be managed in a proactive manner, if possible.
The guideline panel also addressed the following novel treatment methods: high-intensity focused ultrasound, radiosurgery, microwave thermotherapy, laser interstitial thermal therapy, and pulsed cavitational ultrasound.
"Kidney tumors can be the most insidious of urologic tumors, and it is of the utmost importance that they be assessed promptly and thoroughly and that proper treatment be offered," said Campbell, who also serves as the chair of the panel that developed the guidelines. "It is equally important to consider preserving renal function whenever possible."
He said there has been considerable controversy about how to manage early-stage renal masses. In part, this has resulted in overtreatment of many patients. "Our emphasis in the field needs to change from rather than just trying to keep patients off dialysis, to trying to optimize the renal function as we manage these small tumors," Campbell said in an interview. "The most important take-home message is that a nephron-sparing approach is strongly preferred whenever possible. We are in a new era now. If you look at the data in the 1990s and even into this century, the majority of these patients have really still been managed with radical nephrectomy. There is a need to educate practitioners about this and hopefully these guidelines will help."
-John Schieszer
