OBJECTIVE: To report 5 cases of cystic nephroma and review the clinical, diagnostic and therapeutic aspects. METHODS: From 1974 to 1988, 5 cases of cystic nephroma were diagnosed at our hospital. Patient evaluation included IVP and renal US, and occasionally ascending urography, fine needle aspiration biopsy and CT. The cyst was removed through a lumbar incision in 4 patients and nephrectomy in one patient. RESULTS: The patients were followed by yearly ultrasound/urography for 1 to 15 years. No evidence of local recurrence or metastatic disease has been found. CONCLUSIONS: Cystic nephroma is an uncommon, benign kidney disease whose etiology is unknown. Although new imaging techniques are available, surgical excision and histologic analysis of the tumor are the only effective methods to distinguish benign from malignant cystic lesions of the kidney. Because it is a benign lesion, surgery must be conservative. Complete excision of the cyst is advocated. We found a well-encapsulated, noninfiltrating lesion that permitted surgical excision without difficulty in most of our cases. Herniation of some cysts into the urinary tract is a characteristic radiological sign.
OBJECTIVE: To report 5 cases of cystic nephroma and review the clinical, diagnostic and therapeutic aspects. METHODS: From 1974 to 1988, 5 cases of cystic nephroma were diagnosed at our hospital. Patient evaluation included IVP and renal US, and occasionally ascending urography, fine needle aspiration biopsy and CT. The cyst was removed through a lumbar incision in 4 patients and nephrectomy in one patient. RESULTS: The patients were followed by yearly ultrasound/urography for 1 to 15 years. No evidence of local recurrence or metastatic disease has been found. CONCLUSIONS:Cystic nephroma is an uncommon, benign kidney disease whose etiology is unknown. Although new imaging techniques are available, surgical excision and histologic analysis of the tumor are the only effective methods to distinguish benign from malignant cystic lesions of the kidney. Because it is a benign lesion, surgery must be conservative. Complete excision of the cyst is advocated. We found a well-encapsulated, noninfiltrating lesion that permitted surgical excision without difficulty in most of our cases. Herniation of some cysts into the urinary tract is a characteristic radiological sign.