Molecular screening for frequently mutated genes may increase the likelihood of identifying cancer risk groups.
This study, published in the October issue of European Journal of Gastroenterology and Hepatology, investigated the prevalence and time course of p53 and K-ras mutations in colonic lavage fluid of patients with inflammatory bowel disease (IBD).
The research team examined 131 patients with ulcerative colitis (73) and Crohn's disease (58), plus a control group (49 non-tumor, 10 colorectal cancer).
Colonic lavage fluid was studied using oligomer-specific hybridization for K-ras mutations and single-strand conformation polymorphism (SSCP) for p53 mutations.
The team performed follow-up investigations after 1 to 3 years.
The researchers found that mutations were most frequent in carcinomas (50%), but rare in non-tumor controls (2%).
|Colitis mutation frequency:|
- Crohn's colitis = 15%
- Extensive ulcerative = 19%
- Left-sided ulcerative = 13%
- Distal ulcerative colitis = 7%
|European Journal of Gastroenterology and Hepatology|
However, mutations were identified in Crohn's colitis in 15% of patients, in extensive ulcerative colitis in 19%, in left-sided ulcerative colitis in 13%, and in distal ulcerative colitis in 7%.
The team also found a positive association with disease duration.
In addition, follow-up investigations detected the same mutation in 4 patients and revealed new mutations in 3 patients.
Dr Maria Heinzlmann's team concluded, "In our large series of patients with IBD, K-ras and p53 mutations could be detected with reasonable frequency and confirmed at follow-up in at least some patients".
"Our data encourage the use of molecular screening for the detection of malignant precursor lesions in at-risk patients".