The purpose of this review is to describe the potential sources of variability or discrepancy in interpretation of cystic renal masses under the Bosniak v2019 classification system. Strategies to avoid these pitfalls and clinical examples of diagnostic approaches are also presented. Potential pitfalls in the application of Bosniak v2019 are divided into three categories: interpretative, technical, and mass related. An organized, comprehensive review of possible discrepancies in interpreting Bosniak v2019 cystic masses is presented with pictorial examples of difficult clinical cases and proposed solutions. The scheme provided can guide readers to consistent, precise application of the classification system. Radiologists should be aware of the possible sources of misinterpretation of cystic renal masses when applying Bosniak v2019. Knowing which features and types of cystic masses are prone to interpretive errors, in addition to the inherent trade-offs between the CT and MR techniques used to characterize them, can help radiologists avoid these pitfalls.
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This work was partially supported by NIH Grant R01CA154475 (IP).
Conflict of interest
Matthew S. Davenport receives royalties from Wolters Kluwer and uptodate.com. Ivan Pedrosa received an honorarium from Bayer Healthcare and has received stock options from Health Tech International. He also has institutional research agreements with Philips Healthcare and with Siemens Healthcare. Ivan Pedrosa serves on the Scientific Advisory Board for Bayer Healthcare and is a Scientific Advisor for Health Tech International. He has also been a Co-inventor of patents (no royalties received) for Philips Healthcare. Other authors have no disclosures.
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Edney, E., Davenport, M.S., Curci, N. et al. Bosniak classification of cystic renal masses, version 2019: interpretation pitfalls and recommendations to avoid misclassification. Abdom Radiol (2021). https://doi.org/10.1007/s00261-020-02906-8
- Renal cell carcinomas
- Diagnostic error
- Magnetic resonance imaging
- Kidney neoplasms