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

Abstract

PurposeTo systematically assess the diagnostic performance of the Bosniak classification, version 2019 for risk stratification of cystic renal masses.MethodsWe conducted an electronic literature search on Web of Science, MEDLINE (Ovid and PubMed), Cochrane Library, EMBASE, and Google Scholar to identify relevant articles between June 1, 2019 and March 31, 2022 that used the Bosniak classification, version 2019 for risk stratification of cystic renal masses. Summary estimates of sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR−), and diagnostic odds ratio (DOR) were pooled with the bivariate model and hierarchical summary receiver operating characteristic (HSROC) model. The quality of the included studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 tool.ResultsA total of eight studies comprising 720 patients were included. The pooled sensitivity and specificity were 0.85 (95% CI 0.79–0.90) and 0.68 (95% CI 0.58–0.76), respectively, for the class III/IV threshold, with a calculated area under the HSROC curve of 0.84 (95% CI 0.81–0.87). The pooled LR+, LR−, and DOR were 2.62 (95% CI 2.0–3.44), 0.22 (95% CI 0.16–0.32), and 11.7 (95% CI 6.8–20.0), respectively. The Higgins I2 statistics demonstrated substantial heterogeneity across studies, with an I2 of 57.8% for sensitivity and an I2 of 74.6% for specificity. In subgroup analyses, the pooled sensitivity and specificity for CT were 0.86 and 0.71, respectively, and those for MRI were 0.87 and 0.67, respectively. In five studies providing a head-to-head comparison between the two versions of the Bosniak classification, the 2019 version demonstrated significantly higher specificity (0.62 vs. 0.41, p < 0.001); however, it came at the cost of a significant decrease in sensitivity (0.88 vs. 0.94, p = 0.001).ConclusionsThe Bosniak classification, version 2019 demonstrated moderate sensitivity and specificity, and there was no difference in diagnostic accuracy between CT and MRI. Compared to version 2005, the Bosniak classification, version 2019 has the potential to significantly reduce overtreatment, but at the cost of a substantial decline in sensitivity.

CEUS Bosniak Classification—Time for Differentiation and Change in Renal Cyst Surveillance

“…Regarding the four studies [58,60,62,65] 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 [57].…”

“…However, the results were highly heterogeneous. For individual studies, the sensitivity ranged from 0.76 to 1.00, with a specificity of 0.40-0.84 [57]. The 2019 version demonstrated significantly higher specificity (0.62 vs. 0.41, p < 0.001); however, with a significant decrease in sensitivity (0.88 vs. 0.94, p = 0.001) [57].…”

“…The sensitivity and specificity results of eight studies on CT and/or MRI [58][59][60][61][62][63][64][65] were 0.85 (95% CI 0.79-0.90) and 0.68 (95% CI 0.58-0.76), respectively [57]. However, the results were highly heterogeneous.…”

“…A further meta-analysis was performed to evaluate the diagnostic performance of the 2019 Bosniak classification [57]. In the Bosniak Classification 2019, previously subjective descriptions were precisely defined [30]: "thin" is now defined as ≤2 mm, "minimally thick" as 3 mm, and "thick" as ≥4 mm; "few" is defined as 1-3 septa and "many" as ≥4 septa.…”

“…According to the meta-analysis [57] that evaluated the diagnostic performance of the 2019 variation of the Bosniak classification, in five studies [59,60,62,63,65] 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) [57]. In three studies [58,61,64] 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) [57]. There was no significant difference in accuracy between CT and MRI [57].…”