Renal mass biopsy: Why the hesitation?

Combating the misconception that needle provocation may trigger track seeding and cancer cell spread, renal mass biopsy (RMB) has been reported by many to be oncologically safe. Neither a source for pathological upstaging nor unduly reduced survival, RMB has been suggested to be effective in aiding treatment decisions especially in averting unnecessary surgeries and choosing optimal methods [1,2,3]. Diagnostic yield as well as accuracy have also improved. Depending on the size of the tumor and the radiographic approach, diagnosis was made in up to 86% to 100% with accurate histologic subtype or grade in up to 64% to 85%. Latest treatment guidelines from both the American Urological Association (AUA) and the European Association of Urology (EAU) recommend RMB to reduce overtreatment [4,5].

Unfortunately, reality was far from laudatory. In a recent practice pattern survey done in 176 urologic oncologists actively practicing in academic institutions, only 53.4% of the respondents answered they recommended RMB, and even that was in less than 10% of their cases [6]. Another 25.6% never recommended RMB at all. Opinions against biopsy were non-diagnostic results in 55.6% (25 of 45), concerns about track seeding and unchanging treatment plans regardless of the results in 51.1% respectively (23 of 45). Despite much accumulated scientific evidence, RMB was still perceived as risky and frightfully underutilized. Where is the hesitation coming from?

First and foremost, the location and size of the tumor may matter. Percutaneously unapproachable are tumors near the renal hilum or sizable vessels, on the anterior or anteromedial side. Tumors too small may also have low diagnostic yield. Cystic tumors are not recommended candidates. Equally important is an experienced radiologist/interventionist, who can only happen through urologists’ active referral and collaboration. On the other hand, radiographic methods and ancillaries have greatly improved. And biopsy is not ablation; as it does not use energy, potential complications are not as detrimental and self-remitting in most.

Patients present with a variety of health status. Treatment and surveillance options are diversifying. When identification of optimal management strategy for a given patient is in question, it may best begin with gathering as much information. Rest assured, RMB will effectively help in the discussion with patients and their caregivers, and ultimately reduce overdoing as well as underdoing for them.