The clinical implications of telomerase activity in upper tract urothelialcancer and washings

Objective To measure telomerase activity in upper tract urothelial carcinom as las renal pelvic tumours comprise nearly half of all kidney tumours in T aiwan, a much higher percentage than in other countries) and to determine w hether telomerase activity could be used as an additional diagnostic marker in exfoliated cancer cells present in upper tract urothelial washing fluid s, thus providing earlier diagnosis and treatment. Materials and methods Telomerase activity was assessed using the telomeric repeat amplification protocol assay in tissue samples from 31 upper tract u rothelial carcinomas (from 29 patients). The feasibility of identifying can cer using telomerase activity in exfoliated cancer cells in 17 upper tract urothelial washing samples was also investigated, Results Telomerase activity was found in 30 (97%) of the 31 upper tract uro thelial cancer tissue samples; telomerase activity was detectable in 95% of superficial cancers and in all 11 invasive tumours. The sensitivity of mea suring telomerase activity was 100% for grade 1, 93% for grade 2 and 100% f or grade 3 tumours, In contrast, telomerase activity was detected in only t wo (8%) of 26 normal adjacent tissue samples. When the telomerase activity of urothelial washing fluid was compared with that in the corresponding tum ours, there was compatible telomerase activity in 15 of the 17 samples. Tel omerase activity was more sensitive than voided urine cytology (15%) and wa shing fluid cytology (53%). In addition, the telomerase activity was high i n metastatic lesions. Conclusion Telomerase activity is present in most upper tract urothelial ca ncer tissues and may be present at an early stage of carcinogenesis. Telome rase activity can be detected in exfoliated cells in urothelial washing flu ids in a high proportion of patients with upper tract urothelial cancer, Th ese results suggest that measuring telomerase activity in the ex-foliated c ancer cells obtained from urothelial washing could be a potentially useful addition to the conventional diagnostic tools used to identify patients wit h upper tract urothelial carcinoma.