FISH analysis of washing urine from the upper urinary tract for the detection of urothelial cancers

To evaluate FISH analysis of washing urine from the upper urinary tract (UUT) in comparison with cytology (Cyt) for the detection of urothelial cancers.

In 82 patients with symptoms or abnormalities of the UUT sampling of washing urine for FISH and Cyt and a stepwise diagnostic work-up (e.g. retrograde ureteropyelography, ureterorenoscopy and endoscopic biopsy) were performed. In case of endoscopically and/or histologically proven malignancy patients either underwent nephroureterectomy, partial ureterectomy or local treatment. Sensitivity and specificity for FISH and Cyt as well as its combination were determined.

Urothelial cancer of the UUT was detected in 20 patients. Eleven patients underwent nephroureterectomy, six partial ureterectomy and three endoscopic tumour treatment. This revealed nine pTa, three pT1 and seven muscle-invasive tumours. Twelve tumours were classified as low and seven as high-grade tumours. In one patient with a macroscopic unequivocal finding of tumour, endoscopic laser ablation without histologic confirmation was performed. FISH was evaluable in 76 patients and detected 16 tumours with a sensitivity and specificity of 84.2 and 91.1 %, respectively. Cyt was performed in 79 and was evaluable in 78 patients. It detected ten tumours with a sensitivity and specificity of 52.6 and 91.4 %, respectively. Cyt and FISH together detected 19 tumours with (sensitivity 100 % and specificity 83.6 %).

FISH was more sensitive than and equally specific to Cyt in the detection of urothelial cancers of the UUT. Both markers in combination revealed the best sensitivity, making it a possible approach in future settings.