Use of a microsatellite marker in predicting dysplasia in ulcerative colitis.
BACKGROUND
Patients with ulcerative colitis (UC) have an increased risk of developing colorectal cancer. The current screening protocol involves an annual colonoscopy and biopsy after the patient has had the disease for 8 years. This, however, does not prevent the development of colorectal cancer.


OBJECTIVE
A microsatellite marker for IBD1 may identify individuals who are at greater risk of developing dysplasia and therefore colorectal cancer.


METHODS
Case-control study.


METHODS
Single surgical practice.


METHODS
DNA was extracted from peripheral leukocytes of 152 patients: 22 with UC and dysplasia; 48 with UC and no dysplasia; 24 with colorectal cancer; and 58 with noninflammatory bowel disease, nonmalignant gastrointestinal tract disease who were used as control patients. A microsatellite marker for IBD1 (D16S541) was amplified by polymerase chain reaction. Genotypes were identified using autoradiography.


RESULTS
Six alleles and 15 genotypes were identified for marker D 16S541. Genotype CC was found in 33% (8/24) of cancer patients but only 12% (7/58) of controls (chi2 = 5.5; P = .02). Thirty-two percent (7/22) of patients with dysplastic UC also had this genotype, whereas only 8% (4/ 48) of patients with nondysplastic UC had the genotype (chi2 = 4.6; P = .03; vs controls: chi2 = 3.1; P = .08).


CONCLUSIONS
This microsatellite marker for IBD1, when combined with other markers, has the potential to be used as a screening tool for colorectal cancer and dysplasia in patients with UC. Such a marker would be of particular use in improving the sensitivity and specificity of the current screening protocol for dysplasia and colorectal cancer for patients with UC.
Hunt
L E
LE
Price Institute of Surgical Research, Department of Surgery, University of Louisville, KY 40292, USA.
Eichenberger
M R
MR
Petras
R
R
Galandiuk
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001345:Autoradiography; D016022:Case-Control Studies; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000473:pathology; D003093:Colitis, Ulcerative / Q000235:genetics* / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D005838:Genotype; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics*; D008875:Middle Aged; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology; D012306:Risk