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Patterns of
colonic involvement at initial presentation in ulcerative colitis: a
retrospective study of 46 newly diagnosed cases.
Am J Clin Pathol. 2004 Jul;122(1):94-9.
Studies have shown that rectal sparing and patchiness develop in treated
and longstanding ulcerative colitis (UC), making the distinction from
Crohn colitis increasingly difficult after treatment is initiated.
However, no histologic studies of the incidence of rectal sparing in
adults at UC onset have been performed. Colectomy specimens from 46
patients with classic UC histologic features and no Crohn disease features
were identified. Biopsy specimens obtained before medical therapy were
retrieved and examined blindly by 2 pathologists, along with appropriate
control samples. Slides were scored for chronicity (crypt branching,
subcryptal plasma cells, lamina propria plasma cells) and activity (cryptitis,
crypt abscesses, epithelial injury). In 28 cases, only rectal biopsy
specimens were taken; for 16, rectal and at least 1 proximal biopsy
specimen were taken. All cases showed rectal involvement; none had rectal
sparing at initial biopsy. Of 16 cases with rectal and more proximal
biopsy specimens, 5 (31%) showed relative rectal sparing (lower scores in
rectum than in more proximal sites). In 16 cases with rectal and more
proximal biopsy specimens, chronicity and activity scores were higher in
the rectum than in more proximal sites (P = .01; chronicity and activity).
The mean overall chronicity score decreased in a linear manner from rectum
to cecum. The rectum is involved and shows evidence of chronicity and
activity at disease onset in UC, using colectomy as the gold standard for
diagnosis. Because rectal sparing at UC onset has been reported, a
prospective study using uniform biopsy protocols is needed to establish
the true incidence of rectal sparing at presentation.
Chronic
inflammatory bowel disease and cancer.Hepatogastroenterology.
2000 Jan-Feb;47(31):57-70.
Colorectal cancer represents the major cause for excess morbidity and
mortality by malignant disease in ulcerative colitis as well as in Crohn's
disease. The risk for ulcerative colitis associated colorectal cancer is
increased at least 2-fold compared to the normal population and colorectal
cancer is observed in 5.5-13.5% of all patients with ulcerative colitis
and 0.4-0.8% of patients with Crohn's disease. Established risk factors
include long duration of the disease, large extent of the disease, low
activity of the disease, young age at onset, presence of complicating
primary sclerosing cholangitis or stenotic disease and possibly lack of
adequate surveillance, inadequate pharmacological therapy, folate
deficiency and non-smoking. Crohn's disease is associated with an
increased risk of colorectal carcinoma in patients with long-standing
disease, strictures and fistulae under the condition that the colon is
involved, tumors of the small intestine may occur occasionally.
Extracolonic malignancies are rare, with the exception of biliary tract
cancer. Ulcerative colitis associated colorectal cancer typically can
occur in the entire colon, is often multifocal and of undifferentiated
histology. Stage distribution and prognosis of ulcerative colitis
associated colorectal cancer appears to be similar to that of sporadic
colorectal cancer with an overall survival of about 40% (15-65%) after 5
years with tumor stage at diagnosis being the most important predictive
parameter for survival. Tumor markers helpful for the diagnosis of
sporadic colorectal cancer fail to differentiate between inflammatory
response and malignant transformation. In contrast the histologic evidence
of dysplasia was shown to be a strong indicator of underlying carcinoma or
developing malignant transformation. The presence of a surface projection
termed dysplasia associated lesion or mass is highly indicative of
underlying or associated cancer. While the routinely performed search for
dysplasia is hampered by high interobserver variation the demonstration of
DNA-aneuploidy or genetic changes which may confirm the ongoing malignant
transformation has not yet become clinical routine. The genetic
alterations found in ulcerative colitis associated colorectal cancer
involve many of the same targets found in sporadic colorectal tumors and
include multiple sites of allelic deletion, microsatellite instabilities,
and mutations of APC, p53, Ki-ras as well as MSH2 and other genes. The
progression of dysplasia to carcinoma is generally accompanied by an
accumulation of these mutations and the similarities in the biology of
colorectal cancer associated with ulcerative colitis and sporadic
colorectal cancer appear to outweigh their difference. In regard to the
management of dysplasia and cancer, the role of surveillance programs for
the early detection of ulcerative colitis associated colorectal cancer at
a curable stage is still under debate. Although these programs failed at
tumor prevention and lethal carcinomas are still found inadvertently in
patients under surveillance, the majority of surveillance programs could
reduce mortality by detecting more cancers at a still curable stage.
Current recommendations for surveillance include, therefore, biennial
colonoscopy with extensive biopsies after 8-10 years of total colitis or
after 15-20 years of left-sided colitis. In the presence of cancer or
unequivocal high-grade dysplasia and/or dysplasia associated lesion or
mass proctocolectomy is considered adequate. The evidence of low-grade
dysplasia should be confirmed before proctocolectomy is considered.
Cancer
and dysplasia in ulcerative colitis: a histologic study of 301 surgical
specimen.
Z Gastroenterol.
1994 Jul;32(7):382-8.
Patients with ulcerative colitis (UC) have an increased risk to develop
colorectal cancer, and epithelial dysplasia is its common precursor
lesion. Herein, we present the first study on the relationship of
dysplasia and cancer in UC which is based on a systematic histologic
screening policy applied to a series of surgical specimen obtained from
301 patients. Cancer was found in 20 patients (prevalence: 7%), and
dysplasia without cancer was found in additional 12 patients (prevalence:
4%). All 32 UC patients with cancer or dysplasia without cancer featured
at least one high-risk factor for cancer in UC. The median age of UC-cancer
patients was 45 years, while the median age of UC-dysplasia patients was
38 years. In all UC-cancer patients evaluable but one (94%), cancer was
associated with low- or high-grade dysplasia at the cancer margin. In
addition, 71% of UC-cancer patients evaluable had dysplasia at multiple
sites. As a consequence, multiple cancers were found in 6 of 20 patients
(30%). All multiple cancers occurred in the younger patients, none in the
older (p < 0.05). In patients without cancer, however, dysplasia was
limited to one site in the colon or rectum in the majority of cases (55%).
Dysplasia occurred at any site along the colon and rectum, including the
anal transition zone, but no consistent pattern of dysplasia sites was
found. No dysplasia was found in the rectum of 35% of patients with UC-cancer,
and in 45% of patients with dysplasia without cancer, respectively.
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