Bosniak Classification of Cystic Renal Masses Version 2019: Comparison With Version 2005 for Class Distribution, Diagnostic Performance, and Interreader Agreement Using CT and MRI

Diagnostic performance of the Bosniak classification, version 2019 for cystic renal masses: A systematic review and meta-analysis

“…We also performed subgroup analyses for various examinations involving CT and MRI, both alone and in combination. Regarding the four studies reporting the diagnostic accuracy of CT, the pooled sensitivity and specificity were 0.86 (95% CI 0.68–0.95) and 0.71 (95% CI 0.61–0.80), respectively ( 21 , 23 , 25 , 28 ). For the five studies reporting the diagnostic accuracy of MRI, the pooled sensitivity was comparable (0.87, 95% CI 0.78–0.93) but the specificity was lower (0.67, 95% CI 0.48–0.81) ( 22 , 23 , 25 , 26 , 28 ).…”

“…Regarding the four studies reporting the diagnostic accuracy of CT, the pooled sensitivity and specificity were 0.86 (95% CI 0.68–0.95) and 0.71 (95% CI 0.61–0.80), respectively ( 21 , 23 , 25 , 28 ). For the five studies reporting the diagnostic accuracy of MRI, the pooled sensitivity was comparable (0.87, 95% CI 0.78–0.93) but the specificity was lower (0.67, 95% CI 0.48–0.81) ( 22 , 23 , 25 , 26 , 28 ). Regarding the three studies reporting the diagnostic accuracy of CT in combination with MRI, the pooled sensitivity (0.81, 95% CI 0.70–0.91) was lower than using CT or MRI alone, while the specificity was comparable (0.67, 95% CI 0.61–0.82) ( 21 , 24 , 27 ).…”

“…The average tumor size was between 25.4 mm and 65.9 mm, with a malignancy rate of 18.8%–78.1%. Regarding the imaging modalities, four studies reported results from CT ( 21 , 23 , 25 , 28 ),, five reported results from MRI ( 22 , 23 , 25 , 26 , 28 ),, and three reported a combination of results from CT and MRI ( 21 , 24 , 27 ). With respect to the number of radiologists, only one study reported that the images were interpreted by only one reader ( 24 ), whereas in the other seven studies, the images were interpreted by at least two readers.…”

“…The overall quality of the included studies was not very high, primarily due to patient selection ( Figure 2 ). In more than half of the studies, the analysis was restricted to cystic renal masses with confirmed pathological results ( 23 , 25 – 28 ), which may have led to selection and verification biases, as those masses under surveillance that did not undergo histological confirmation were not included. Regarding the reference standard, two of the studies used the availability of at least five years of follow-up data, rather than histopathological findings, as the reference standard for some patients ( 21 , 22 ).…”

“…We compared the Bosniak classification, version 2019 with version 2005 across five studies that provided a head-to-head comparison ( 22 , 23 , 25 – 27 ). The pooled sensitivity of 0.88 (95% CI 0.76–0.95) vs. 0.94 (95% CI 0.89–0.98), respectively, suggests that the new version is significantly inferior to the previous one ( p = 0.001).…”