Dr Alashkham and his colleagues have published a paper in the British Institute of Radiology (BIR). Paper abstract: Objectives: To determine the safety and diagnostic accuracy of renal tumour biopsies in a defined population of small renal masses only <4cm using 3x2 table, intention to diagnose approach. 3x2 table approach examines indeterminate results as a separate category rather than pushing these through traditional 2x2 table (four-cell matrix) approach. Methods and Materials: A highly sensitive search was performed in the Cochrane Library, Database of Abstracts of Reviews of Effects; MEDLINE and MEDLINE in Process, EMBASE and conference proceedings (1966 to 2016) for the acquisition of data on the diagnostic accuracy and complications of RTB in patients with SRM <4cm. Methodological quality and risk of bias was assessed using QUADAS-2. Test characteristics were calculated using conventional 2x2 contingency table analysis excluding non-diagnostic biopsies, and an intention-to-diagnose approach with a 3x2 table for pooled estimates of the sensitivity and specificity. Results: A total of 20 studies were included, with a total sample size of 974. The pooled estimates for sensitivity and specificity of RTB based upon univariate analysis using 2x2 table observed sensitivity .952 (CI 0.908 - 0.979) and specificity 0.824 (CI 0.566 - 0.962). Using the 3x2 table and intention-to-diagnose principle, sensitivity .947 (CI 0.925 - 0.965) and specificity 0.609 (CI 0.385 - 0.803) decreased. Conclusions: Renal tumour biopsy in small renal masses (<4cm) is associated with a high diagnostic sensitivity but poor specificity when non-diagnostic results are included by a 3×2 table for analysis (intention to diagnose approach). Risk of non-diagnostic results and poor quality of research need addressing through future studies, preferably by a well-designed prospective study appropriately powered for diagnostic accuracy using valid reference standards. Related links Diagnostic accuracy of image-guided biopsies in small (<4 cm) renal masses with implications for active surveillance: a systematic review of the evidence Publication date 05 Sep, 2018
