Varied terminology by radiologists to describe Bosniak class III and IV cystic renal masses

Background The Bosniak classification is designed to standardize evaluation of cystic renal masses and to communicate the risk of malignancy. Purpose To determine whether radiologists vary in their communication of Bosniak class III and IV cystic renal masses. Material and Methods This retrospective study included 186 patients with CT or MRI reporting a Bosniak class III or IV mass. Radiology reports were evaluated to determine the noun representing the mass, the modifier to convey the likelihood of cancer, and recommendations for urologic referral. Electronic medical records were reviewed to determine if the patient saw a urologist. Results Of the patients, 112 (60%) had a class III mass and 74 (40%) had a class IV mass. Class III masses were more likely to be represented by the noun “lesion” rather than a “mass” (61/112 [54%] vs. 31/112 [28%]). Class IV masses are more likely to be represented as a “mass” (36/74 [59%] vs. 28/74 [38%]; P < 0.015). Cancer was described in 100/186 (54%) cases: 38/112 (35%) class III masses and 62/74 (72%) class IV masses ( P < 0.001). The cancer terminology used included “renal cell carcinoma” (n = 57), “neoplasm” (n = 12), and “malignancy/malignant” (n = 86). Most radiology reports (n = 133, 72%) did not recommend urologic referral but 183 (98%) patients were referred and 181 (97%) ultimately saw a urologist. Conclusion Radiologists vary in their communication of class III and IV masses, reflecting historical terminology usage, nuanced interpretations, and an evolving understanding of renal cell carcinoma biology. This variance had minimal impact on urologic referral rates.