[Cystic cancer of the kidney]

Cystic renal cancer is uncommon and raises real preoperative diagnostic problems, requiring the use of medical imaging, and sometimes even surgery. The authors report 3 cases of cystic renal cancer in 2 men and 1 woman, aged 87, 67 and 20 years, respectively. Three patients presented with the urological triad (haematuria, pain and lumbar mass). Ultrasonography suggested the diagnosis of cystic cancer in all 3 cases. Computed tomography was performed in 2 patients and more precisely confirmed the ultrasound findings. Selective arteriography, performed in one patient, confirmed the hypothesis of malignancy. Surgical exploration resulted in radical total nephrectomy. Histology confirmed the diagnosis of adenocarcinoma. The course was favourable in 2 cases after a follow-up of 4 years. One patient presented a local recurrence with pulmonary metastases 6 months after the operation. A review of the literature illustrates the diagnostic difficulties of this form of renal cancer.