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Bosniak renal cyst - type IV

Case contributed by Dr Andrew Dixon


Incidental complex renal cyst on ultrasound.

Patient Data

Age: 60 years
Gender: Male

Triphasic Renal CT


Cystic left renal lower pole mass with enhancing nodular components and multiple thick enhancing septations. Appearance is consistent with a 'clearly malignant' Bosniak IV renal cyst.


An illustrative example of a Type IV cyst

Case Discussion

Nephrectomy was performed and the lesion was confirmed to be a renal cell carcinoma, as was an adjacent smaller lesion which can be seen directly superior to the larger mass.  

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