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Produced: 03/26/2026 3:14 PM
Question 20200059
Inquiry Details
References:
Question:
Reportability--Kidney: Is Bosniak 4 cystic lesion of right kidney reportable, and would the first CT date be the date of diagnosis? See Discussion.
Discussion:
CT a/p read by radiologist shows: "Bosniak 4 cystic lesion of right kidney." Follow-up MRI a month later reads "right kidney cystic lesion with enhancing mural nodule concerning for cystic renal cell carcinoma (RCC)." Urologist consult used the same wording of "Bosniak 4 cystic lesion" and "concerning for renal cell carcinoma." Treatment discussed but due to patient health status recommended repeat imaging. Repeat CT few months later reads: "cystic right renal lesion with enhancing nodule similar to most recent prior and suspicious for cystic RCC."
Though "suspicious for cystic RCC" per latest imaging is reportable, Bosniak 4 is "clearly malignancy, ~100% malignant" by definition, so is the case actually reportable with the first CT a/p date as date of diagnosis?
Answer:
2023
Bosniak 4 is defined as "clearly malignant cystic mass." The case is reportable as of the first date it is diagnosed as a Bosniak 4 lesion unless further workup (especially biopsy or resection) disproves the CT findings.
https://radiopaedia.org/articles/bosniak-classification-system-of-renal-cystic-masses?lang=us
History:
2020 - 2022
Bosniak 4 is defined as "clearly malignant; ~100% malignant." The case is reportable as of the first date it is diagnosed as a Bosniak 4 lesion unless further workup (especially biopsy or resection) disproves the CT findings.
