What a renal cyst can hide
In the last 4 years 12 patients underwent nephrectomy for spontaneous breaking of renal cysts and discovered a kidney cancer. We show last three clinical cases at our hospital.
First patient was 65 years old and was followed for a renal cyst. In December 2014 he reached our emergency department with left lumbar pain and underwent a TC. In the contest of left kidney, TC showed a cyst with non-uniform wall thickening, blood clots, without contrast enhancement ( Bosniak II). He underwent nephrectomy and microscopic examination showed a papillary renal cells tumors (type 2) with hemorrhagic necrosis in the contest.
Second patient was 31 years old and was followed for a bilateral polycystic kidney disease. In November 2014 he reached our emergency department after an abdominal trauma and underwent a TC. In the contest of a polycystic kidney, TC showed a right cyst with blood clots, without contrast enhancement (hemorrhagic renal cyst. He underwent nephrectomyand microscopic examination showed a cystic renal cell carcinomas.
Last patient was 42 years old and in October 2014 reached our emergency department with abdominal pain. He underwent a TC that showed a left renal cyst with non-uniform wall thickening, without contrast enhancement and calcifications (Bosniak II cyst). He underwent nephrectomyand microscopic examination showed hemorrhagic necrosis and a papillary renal cells tumors(type 2) with capsular invasion.
Differentiating between complex cystic renal masses that require surgery and those that do not remains a common and difficult diagnostic problem. If these patients had not had an acute event, they would not discover a kidney cancer. Renal tumors and benign complicated cysts can be indistinguishable at imaging and assigning a definitive diagnosis can require an histologic examination. A very short follow-up term or other diagnostic devices as RM or contrast-enhanced ultrasound (CEUS) can help in differential diagnosis.