囊狀腎瘤以腎細胞癌方式呈現-案例報告及文獻回顧

陳約任^a,b、薛又仁^c,d、邱文祥^c,d

^a桃園長庚醫院醫教部

^b長庚大學醫學院

^c臺北市立聯合醫院仁愛院區外科部泌尿科

^d國立陽明大學醫學院醫學系泌尿學科

Cystic Nephroma Masquerading as Renal Cell Carcinoma – A Case Report and Review of Literature

Jonathan YJ Chen ^a,b, Thomas Y. Hsueh ^c,d, Allen W. Chiu ^c,d

^a Department of Medical Education, Chang Gung Memorial Hospital, Taoyuan

^b School of medicine, Chang Gung University, Taoyuan

^c Division of Urology, Department of Surgery, Taipei City Hospital Renai Branch, Taipei

^d Department of Urology, School of Medicine, National Yang-Ming University, Taipei

Purpose:

Cystic nephroma is a benign renal mass mimicking malignancy. Pre-operative diagnostic images offer limited assistance for differential diagnosis. We describe a male with accidentally found cystic renal tumor with the tentative diagnosis of renal cell carcinoma.

Materials and Methods:

A 59 year-old male presented to urologic clinic with an accidentally found left renal tumor. There was no abdominal pain or palpable abdominal mass. Abdominal computed tomography revealed a multi-locular, well circumscribed cystic lesion at left kidney with 3.8 x 3.2 x 2.5 cm in size with intra-cystic calcification and enhancing septations, indicating a Bosniak III cystic mass.

Results:

The patient underwent laparoscopic partial nephrectomy, but conversion to radical nephrectomy due to dense peri-renal adhesion during operation. Histopathology report showed multi-locular cysts lined by flat, cuboidal and hobnail cells separated by fibrous septa that have a stroma-like appearance with focal hyaline fibrosis. Immunohistochemical staining showed focally positive ER, PR, and desmin for stromal cells. Cysts lined cells showed positive CK and negative EMA.

Conclusion:

It’s still difficult to differentiate between cystic nephroma and cystic renal cell carcinoma. Although pre-operative imaging could not provide a definite diagnosis for cystic nephroma, it should be considered in patients with multi-locular cystic renal lesions.