Cystic renal cell carcinoma — rare clinical finding Radiographic variations of tumor/cyst appearance and further diagnostic work-up

OBJECTIVES: To review the cases of cystic renal cell carcinoma and multilocular cystic nephroma, point out the radiographic variations and define further diagnostic work-up. MATERIALS AND METHODS: Between 2003 and 2005 5 patients with suspected cystic renal cell carcinoma were treated surgically (1 pt underwent radical nephrectomy, 1 pt laparoscopic cyst decortication, 3 pts ablation), 2 patients with multilocular cystic nephroma underwent ultrasound guided biopsy. RESULTS: Histopathologic examination confirmed cystic renal cell carcinoma (CRCC) T1aNOM0 Fuhrman grade 1 in 3 cases, T1bN0M0 Fuhrman grade 2 in one case. One patient with suspected tumor inside the cyst wall who underwent laparoscopic cyst decortication was excluded (final histology confirmed organized hematoma in the cyst wall). Biopsy in 2 patients with multilocular cystic nephroma did not confirm the presence of malignant cells. The mean tumor size was 4.2 cm (range 3.7 to 5.5) for CRCC and 4.7 cm (range 4 to 4.5 cm) for multilocular cystic nephroma. All 4 cases of CRCC were clear cell type. CONCLUSION: In conclusion according to the data described and from our study, tumor/cyst co-existence requires further surgical exploration in group 2, 3, 4. Small cystic renal cell carcinomas up to 4 cm in diameter have usually favourable pathology and prognosis, which offers the minimally invasive nephron-sparing treatment options such as excision, ablation or partial nephrectomy (Fig. 9, Ref. 18).