Evolution of Bosniak IIF Renal Cysts and Impact of the 2019 Bosniak Classification

No AccessJournal of UrologyAdult Urology1 Apr 2023Evolution of Bosniak IIF Renal Cysts and Impact of the 2019 Bosniak ClassificationThis article is commented on by the following:Editorial CommentEditorial Comment Félix Couture, Sarah Hadj-Mimoune, Stéphane Michael, Teodora Boblea Podasca, Maxime Noël-Lamy, and Patrick O. Richard Félix CoutureFélix Couture Department of Urology, Centre Hospitalier de l’Université de Montréal, Montréal, Quebec, Canada Department of Urology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author , Sarah Hadj-MimouneSarah Hadj-Mimoune Department of Radiology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author , Stéphane MichaelStéphane Michael Department of Radiology, Centre Hospitalier de l’Université Laval, Québec, Quebec, Canada More articles by this author , Teodora Boblea PodascaTeodora Boblea Podasca Department of Urology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author , Maxime Noël-LamyMaxime Noël-Lamy Department of Radiology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author , and Patrick O. RichardPatrick O. Richard *Correspondence: Division of Urology, Department of Surgery, Centre Hospitalier Universitaire de Sherbrooke, 3001, 12e Ave N, Sherbrooke, Quebec J1H 5N4, Canada telephone: 819-346-1110, ext. 74595; E-mail Address: [email protected] Department of Urology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003112AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: The follow-up of Bosniak IIF renal cysts is associated with significant costs, radiation, and anxiety. Recent studies have suggested a risk of malignancy and upgrading lower than previously reported. We aimed to determine their clinical outcomes and to evaluate the impact of the 2019 Bosniak classification on the diagnosis of such lesions. Materials and Methods: We identified all radiology reports with the diagnosis of a Bosniak IIF cyst at our institution between January 2000 and December 2018. Imaging was reviewed to confirm the diagnosis and determine progression based on the 2005 Bosniak classification. Radiological and clinical characteristics were established, and the 2019 Bosniak criteria were retrospectively applied. Results: Out of 252 cysts reviewed, 55 (22%) were reclassified as Bosniak II upon revision using the 2005 Bosniak classification. A total of 181 Bosniak IIF cysts were included for final analysis. The median imaging follow-up was 50 months. Four (2.2%) cysts progressed to Bosniak III or IV. Five (2.8%) patients underwent surgical interventions, with only 1 malignant pathology being reported. No malignant progression was observed after 36 months. When applied to our cohort, the 2019 Bosniak classification would have led to a 76% decrease in Bosniak IIF diagnoses, with no increase in Bosniak III or IV diagnoses, and identical classification of the confirmed malignant pathology. Conclusions: Upgrading and malignancy rates among Bosniak IIF cysts was markedly lower than traditionally reported. No patient had a significant progression beyond 36 months. More than 20% of Bosniak IIF cysts were initially overdiagnosed. The 2019 Bosniak classification may help to reduce the overdiagnosis of Bosniak IIF lesions requiring follow-up. REFERENCES 1. . Incidence and growth pattern of simple cysts of the kidney in patients with asymptomatic microscopic hematuria. Int J Urol. 2003; 10(2):63-67. Crossref, Medline, Google Scholar 2. . The current radiological approach to renal cysts. Radiology. 1986; 158(1):1-10. Crossref, Medline, Google Scholar 3. . An update of the Bosniak renal cyst classification system. Urology. 2005; 66(3):484-488. 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Instructions for obtaining credits are given with the questions on pages 816 and 817. © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetailsCited byRichard P and Couture F (2023) Evolution of Bosniak IIF Renal Cysts and Impact of the 2019 Bosniak Classification. Reply.Journal of Urology, VOL. 209, NO. 5, (844-845), Online publication date: 1-May-2023.Shen L and Tse J (2023) Evolution of Bosniak IIF Renal Cysts and Impact of the 2019 Bosniak Classification. Letter.Journal of Urology, VOL. 209, NO. 5, (844-844), Online publication date: 1-May-2023.Siemens D (2023) This Month in Adult UrologyJournal of Urology, VOL. 209, NO. 4, (653-654), Online publication date: 1-Apr-2023.Bhindi B (2023) Editorial CommentJournal of Urology, VOL. 209, NO. 4, (700-700), Online publication date: 1-Apr-2023.Akhtar O (2023) Editorial CommentJournal of Urology, VOL. 209, NO. 4, (699-700), Online publication date: 1-Apr-2023.Related articlesJournal of Urology17 Feb 2023Editorial CommentJournal of Urology17 Feb 2023Editorial Comment Volume 209Issue 4April 2023Page: 694-700 Peer Review Report Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.Keywordskidney neoplasmsMetricsAuthor Information Félix Couture Department of Urology, Centre Hospitalier de l’Université de Montréal, Montréal, Quebec, Canada Department of Urology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author Sarah Hadj-Mimoune Department of Radiology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author Stéphane Michael Department of Radiology, Centre Hospitalier de l’Université Laval, Québec, Quebec, Canada More articles by this author Teodora Boblea Podasca Department of Urology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author Maxime Noël-Lamy Department of Radiology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada More articles by this author Patrick O. Richard Department of Urology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada *Correspondence: Division of Urology, Department of Surgery, Centre Hospitalier Universitaire de Sherbrooke, 3001, 12e Ave N, Sherbrooke, Quebec J1H 5N4, Canada telephone: 819-346-1110, ext. 74595; E-mail Address: [email protected] More articles by this author Expand All Support: None. Conflict of Interest: POR: Consultant: Bayer, Janssen, Knight, Astellas; Honorarium: Astellas, Abbvie, Amgen, Janssen, Knight, Bayer, Tolmar. Ethics Statement: This study received Institutional Review Board approval (IRB No. 2020-3529). Editor's Note: This article is the first of 5 published in this issue for which Category 1 CME credits can be earned. Instructions for obtaining credits are given with the questions on pages 816 and 817. Advertisement PDF downloadLoading ...