新北市立土城醫院 外科部 泌尿科
Multilocular Cystic Renal Neoplasm of Lower Malignant Potential (MCRNLMP) Presented as a Complex Cyst: A Case Report
Ying-Hsu Chang, Chung-Yi Liu, Wei-Chang Lee
Depart of Urology, New Taipei Municipal TuCheng Hospital, Chang Gung Memorial Hospital and Chang Gung University
MCRNLMP is a quite rare subtype of clear cell renal cell carcinoma and accounts for less than 1% of renal s. The diagnostic criteria for MCRNLMP were defined by the 2016 WHO classification of kidney tumors as a neoplasm of kidney composed entirely of cysts with small groups of non-expansile clear cells in the septa. Herein, we presented a case of MCRNLMP, and discussion clinical finding.
The patient was a 50 years old male without any systemic disease. He received health examination and revealed left renal complex cyst one year ago. Then, he was regular followed up at our department. Due to left renal cyst still noted and abdominal CT/MRI suspected malignancy. The patient received left partial nephrectomy. Final pathology showed MCRNLMP. No more adjuvant therapy was done. The patient quite well till now.
MCRNLMP is frequently misdiagnosed as a benign renal cyst because it showed similar clinical manifestations and imaging characteristics. This tumor with male predominance (male to female 3:1), and age ranges from 20 to 76 years. Macroscopically, MCRNLMP is characterized by having a variegated multilocular cystic appearance. Microscopically, MCRNLMP is composed of multiple cysts separated by fibrous septum lined by tumor cells with clear cytoplasm that have low nuclear grade (ISUP/WHO grade 1 or 2). There are small aggregates of tumor cells but no formation of expansile nodules are seen. There is no necrosis, vascular invasion or sarcomatous differentiation were founded in MCRNLMP. No instance of tumor progression is known. MCRNLMP is rare tumor carries an excellent prognosis. Radical nephrectomy is avoided as in conventional renal cell carcinoma. Surgical removal of cyst with clear margin is adequate.