Rationale for percutaneous biopsy and histologic characterisation of renal tumours.

CONTEXT: The use of percutaneous biopsy of renal tumours has been traditionally reserved for selected cases because of uncertainties regarding its safety, accuracy, and clinical utility. With the adoption of modern biopsy techniques and increasing expertise in interpreting biopsy specimens, renal tumour biopsy today has limited morbidity and allows histologic diagnosis in the majority of cases in centres with expertise.
OBJECTIVE: To review the current rationale, indications, and outcomes of percutaneous biopsies and histologic characterisation of renal tumours. EVIDENCE ACQUISITION: We conducted a systematic review of English-language articles on percutaneous biopsies of renal tumours published between January 1999 and December 2011 using the Medline, Embase, and Web of Science databases. One hundred twelve articles were selected with the consensus of all authors and analysed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) criteria. EVIDENCE SYNTHESIS: In recent years, the increasing incidence of incidental small renal masses (SRMs), the development of conservative and minimally invasive treatments for low-risk renal cell carcinoma (RCC), and the discovery of novel targeted treatments for metastatic disease have provided the rationale for expanding the indications for renal tumour biopsy. Percutaneous biopsy for diagnostic assessment of SRMs can avoid unnecessary surgeries and support treatment decisions, especially in patients at high surgical risk. Biopsies can confirm histologic success after thermal ablation of SRMs and support the selection of the appropriate systemic therapy for metastatic RCC. There is increasing evidence that further diagnostic and prognostic information can be obtained from renal tumour biopsies with the use of immunohistochemistry, cytogenetic and molecular analysis, and high-throughput gene expression profiling.
CONCLUSIONS: Percutaneous biopsies have increasing indications and can significantly contribute to clinical management of renal tumours but are still underutilised in clinical practice. Further research is needed to define optimal and standardised patterns of biopsy and improve the accuracy of biopsies to determine tumour histology. Molecular and genetic analysis of biopsy specimens can provide additional information to support patient counselling and treatment decision making.