Small renal mass biopsy – how, what and when: report from an international consensus panel

Abstract

To discuss the use of renal mass biopsy (RMB) for small renal masses (SRMs), formulate technical aspects, outline potential pitfalls and provide recommendations for the practicing clinician. The meeting was conducted as an informal consensus process and no scoring system was used to measure the levels of agreement on the different topics. A moderated general discussion was used as the basis for consensus and arising issues were resolved at this point. A consensus was established and lack of agreement to topics or specific items was noted at this point. Recommended biopsy technique: at least two cores, sampling different tumour regions with ultrasonography being the preferred method of image guidance. Pathological interpretation: ‘non‐diagnostic samples’ should refer to insufficient material, inconclusive and normal renal parenchyma. For non‐diagnostic samples, a repeat biopsy is recommended. Fine‐needle aspiration may provide additional information but cannot substitute for core biopsy. Indications for RMB: biopsy is recommended in most cases except in patients with imaging or clinical characteristics indicative of pathology (syndromes, imaging characteristics) and cases whereby conservative management is not contemplated. RMB is recommended for active surveillance but not for watchful‐waiting candidates. We report the results of an international consensus meeting on the use of RMB for SRMs, defining the technique, pathological interpretation and indications.

Active surveillance for clinically localized renal tumors: An updated review of current indications and clinical outcomes

“…Percutaneous RTB currently plays an important role in the evaluation of SRM, and its application in clinical practice is progressively increasing, thanks to more convincing proof of safety and accuracy. 33 In the latest series, indeed, RTB morbidity was found to be very low, as well as the incidence of highgrade complications. In a recent review of the literature, Volpe et al summarized the rationale and outcomes of renal tumor biopsy.…”

“…26 The retroperitoneal hematoma, as a result of parenchymal bleeding after RTB, generally represents the most frequent event, but very rarely requires surgical treatment or embolization. 26,33 The fear of malignant cells' needle-tract seeding could represent another argument against the use of RTB. Although in the past few cases of cancer dissemination along the percutaneous tract have been reported, in the modern series, with the use of coaxial biopsy techniques, the reports of tumor seeding have been anecdotal.…”

“…14,34 Although in most cases a correct histological subtyping can be obtained in a single RTB core, the definition of the correct diagnosis in hybrid tumors (where different histological architectures are simultaneously present within the same mass) could be challenging. 33 Similarly, it might be difficult to distinguish chromophobe RCC from oncocytomas, even with the aid of immunohistochemical markers. 33 Even though the diagnostic accuracy is progressively improving, according to the current recommendations not all patients with SRM are ideal candidates to RTB, but only those patients in which a percutaneous biopsy is going to impact the future clinical management.…”

“…33 Similarly, it might be difficult to distinguish chromophobe RCC from oncocytomas, even with the aid of immunohistochemical markers. 33 Even though the diagnostic accuracy is progressively improving, according to the current recommendations not all patients with SRM are ideal candidates to RTB, but only those patients in which a percutaneous biopsy is going to impact the future clinical management. 14,35 In these different scenarios, RTB could reduce the morbidity of unnecessary procedures and, in contrast, maximize treatment effectiveness.…”

Küçük Renal Kitlelerde Biyopsi ve İzlem

“…Biyopsi için düşük morbidite oranıyla, tanı için yeterli doku örneği sağlayan 18 G iğne idealdir. Tümör ekiminden kaçınmak ve birden fazla biyopsi almaya yardımcı olması bakımından ko-aksiyel kanül kullanılması önerilmektedir (10 (11). Ancak şunu da belirtmek gerekir ki; biyopsinin histolojik doğruluk oranı yüksek iken (%90), nükleer derecelendirmede doğruluk oranı yetersizdir (%62) (8).…”