Genetic variations in the inflammation pathway may predict who would respond to Bacillus-Calmette-Guerin (BCG) treatment and who might experience a recurrence among patients with non-muscle invasive bladder cancer, according to data presented at the American Association for Cancer Research 100th Annual Meeting 2009.
"Our goal is to use genetic information like this to create a genetic blueprint for this disease, which currently recurs in about 70 percent of patients despite initial successful therapy," said Xifeng Wu, M.D., Ph.D., senior author of the study and a professor in the department of epidemiology at the University of Texas M.D. Anderson Cancer Center, where the research was conducted.
Hushan Yang, Ph.D., a postdoctoral fellow at M. D. Anderson and the first author of this study, and colleagues evaluated a panel of 59 single nucleotide polymorphisms in 35 major inflammation genes in all participants that had been treated with BCG therapy, the current treatment standard for non-muscle invasive bladder cancer.
If a patient had a genotype containing the variant allele of the iNOS gene, there was a significant reduction in the risk of recurrence compared with those patients who did not have this variance.
"Survival associated with this variance was 96.7 months compared with 47.0 months among patients with the wild-type gene," Yang said.
In a further analysis, Yang and colleagues calculated a variance combination to identify those patients at high risk for recurrence. The overall median recurrence-free survival time in this group was only 13.5 months compared with more than 96.7 months, or indefinitely, in the low-risk group.
"These genes can be measured through simple blood tests," said Wu. "Once we identify the patients at high risk for recurrence we can adjust their therapy and followup accordingly."