CAM ConferenceMicrosatellite Analysis More Sensitive Than Cytology In Bladder Cancer
A DGReview of :”Sensitive detection of transitional cell carcinoma of the bladder by microsatellite analysis of cells exfoliated in urine”
International Journal of Cancer: Predictive Oncology
By Mark Greener
Microsatellite analysis is a more sensitive technique for the detection of bladder cancer cells in urine than conventional cytology.
Transitional cell carcinoma is the most common bladder cancer. Urine cytology detects most high-grade tumours, however, sensitivity declines as the grade falls.
Many neoplasms, including bladder cancer, express alterations in microsatellite markers. So, researchers from IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, and other Italian centres, assessed whether microsatellite analysis facilitates the detection of bladder cancer cells in urine.
The authors enrolled 21 patients with symptoms suggesting that they may have bladder cancer, 23 who previously had transitional cell carcinoma and 11 healthy controls. They assessed 20 microsatellite markers in urine samples for loss of heterozigosity (LOH) and microsatellite instability.
Microsatellite analysis detected primary or recurrent tumours in 97 percent of the patients shown to have one of these conditions. In contrast, urine cytology detected only 79 percent of these patients.
Indeed, microsatellite analysis increased the sensitivity of detecting grades G1-G2 bladder cancer from 75 to 95 percent. The sensitivity for detecting pTis-pTa tumours increased from 75 to around 100 percent.
The authors also took bladder washings from 25 patients. The results were identical to those from voided urine. In one patient, who showed chronic abnormalities of the bladder mucosa, microsatellite alterations emerged eight months before the tumour recurred on histopathology.
On the other hand, none of the urine samples or bladder washings from the 16 patients who, without evidence of transitional cell carcinoma, showed either loss of heterozigosity or microsatellite instability.
The authors concluded that microsatellite marker analysis is more sensitive than conventional urine cytology for detecting bladder cancer cells in urine. Microsatellite marker analysis may offer a potential clinical tool to detect and monitor low-grade and early stage transitional cell carcinomas.
International Journal of Cancer 2001;95:364-369