BERKELEY, CA (UroToday.com) - It seems to have become a recurring theme of discussion among urologists that intravesical bacillus Calmette-Guérin (BCG) immunotherapy, while effective in a certain population of patients, can also be seen as simply delaying the inevitable in another subgroup of patients.
In an effort to be able to predict whether or not an individual patient will respond to BCG, our group at MD Anderson Cancer Center has launched ongoing efforts trying to identify urine, tissue, and serum-based biomarkers related to treatment with BCG immunotherapy.
In this article we have reported on our prospective clinical trial at MD Anderson Cancer Center investigating the role of fluorescence in-situ hybridization (FISH) in predicting response to intravesical BCG immunotherapy. In order to understand the relevance of ‘molecular recurrence’ as determined by UroVysion® FISH testing, we performed analyses on urine specimens from patients with non-muscle invasive bladder cancer at multiple time points throughout their treatment with BCG. While we confirmed that the results of a FISH assay correlate with risk of tumor recurrence and progression as shown in other studies, even more relevant are our findings that as patients accumulate multiple abnormal FISH results during their course of BCG therapy they are even more likely to recur and/or progress.
The implication of these findings is important in counseling patients. In particular, if a patient develops a pattern of FISH results that is suggestive of a very high likelihood of recurrence or progression during BCG immunotherapy, they may benefit from premature cessation of BCG therapy and earlier surgical intervention with radical cystectomy for curative intent (or enrollment into alternative treatment protocols). On the other hand, if a patient develops a pattern of FISH results that is suggestive of a very low likelihood of disease recurrence, the surveillance strategy could potentially be modified to utilize less frequent evaluations with cystoscopy and imaging, which would significantly lower costs in caring for patients with this disease. Finally, this assay may be used to design future clinical trials, potentially selecting patients with current evidence of a molecular, but not clinical, recurrence thus enhancing recruitment.
Rian J. Dickstein, MD and Ashish M. Kamat, MD, FACS as part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.