The occurrence of severe epithelial dysplasia and its bearing on treatment of longstanding ulcerative colitis

Colorectal Neoplasia and Inflammatory Bowel Disease

Inflammatory bowel disease is associated with an increased risk of gastrointestinal neoplasia. Ulcerative colitis increases the risk of colorectal cancer, and patients with this condition should undergo routine colonoscopic surveillance to detect neoplasia. Crohn's disease increases the risk of malignancy in inflamed segments of bowel, which may include small bowel, colon, rectum, and anus.

Dysplasia in ulcerative colitis as a predictor of unsuspected synchronous colorectal cancer

BACKGROUND

Endoscopic surveillance of patients with ulcerative colitis aims to prevent cancer-related morbidity through the detection and treatment of dysplasia. The literature to date varies widely with regard to the importance of dysplasia as a marker for colorectal cancer at the time of colectomy.

OBJECTIVE

The aim of this study was to accurately characterize the extent to which the preoperative detection of dysplasia is associated with undetected cancer in patients with ulcerative colitis.

DESIGN/PATIENTS/SETTING

A retrospective chart review was conducted of patients undergoing surgery for colitis within the Mayo Clinic Health System between August 1993 and July 2012.

MAIN OUTCOME MEASURES

Patient demographics and pre- and postoperative dysplasia were tabulated. The relationship between pre- and postoperative dysplasia/cancer in surgical pathology specimens was assessed.

RESULTS

A total of 2130 patients underwent abdominal colectomy or proctocolectomy; 329 patients were identified (15%) as having at least 1 focus of dysplasia preoperatively. Of these 329 patients, the majority were male (69%) with a mean age of 49.7 years. Unsuspected cancer was found in 6 surgical specimens. Indeterminate dysplasia was not associated with cancer (0/50). Preoperative low-grade dysplasia was associated with a 2% (3/141) risk of undetected cancer when present in random surveillance biopsies and a 3% (2/79) risk if detected in endoscopically visible lesions. Similarly, 3% (1/33) of patients identified preoperatively with random surveillance biopsy high-grade dysplasia harbored undetected cancer. Unsuspected dysplasia was found in 62/1801 (3%) cases without preoperative dysplasia.

LIMITATIONS

This study is limited by its retrospective nature and by its lack of evaluation of the natural history of dysplastic lesions that progress to cancer.

CONCLUSIONS

The presence of dysplasia was associated with a low risk of unsuspected cancer at the time of colectomy. These findings will help inform the decision-making process for patients with ulcerative colitis who are considering intensive surveillance vs surgical intervention after a diagnosis of dysplasia.

Cancer surveillance strategies in ulcerative colitis: the need for modernization

The risk of colorectal cancer is increased in patients with long-standing ulcerative colitis. Traditional surveillance has centered around regular standard white-light colonoscopy, with multiple biopsies aimed at detecting dysplasia or the identification of early cancer. This has resulted in only a modest reduction in cancer incidence and mortality. A better understanding of disease risk factors may allow endoscopic resources to be more focused on patients at higher risk. In addition, advanced endoscopic techniques have the potential to improve dysplasia detection, minimize the need for routine biopsies, and allow for the removal of dysplastic lesions, avoiding the need for surgery. Techniques such as magnification colonoscopy, chromoendoscopy, narrow band imaging, autofluorescence, and confocal endomicroscopy may all have a role to play in improving the benefits of endoscopic surveillance. Revised endoscopic surveillance strategies are proposed, incorporating aspects of risk stratification, a well-established practice in noncolitis-related colorectal cancer screening, and some of these new technologies.

Cancer in inflammatory bowel disease

Patients with inflammatory bowel disease, including both ulcerative colitis (UC) and Crohn's disease, are at increased risk for the development of gastrointestinal carcinoma, particularly colorectal adenocarcinoma. The current options to reduce this cancer risk include prophylactic colectomy, periodic endoscopic screening with colectomy performed in those patients found to have dysplastic colonic mucosa, or expectant management with no routine surveillance regimen. Despite the lack of data demonstrating effectiveness of surveillance colonoscopy, this approach has become the standard of care in most communities in the United States. Although it has fallen out of fashion in recent years, prophylactic colectomy remains a good option for reducing cancer risk for select patients with UC.

Hazard rates for dysplasia and cancer in ulcerative colitis. Results from a surveillance program

The risk of colon cancer in patients with ulcerative colitis is related to the duration and extent of disease. Prior reports have suggested that patients with onset of disease in childhood have a high risk of cancer. These risk factors were analyzed in 99 patients in a surveillance program of annual colonoscopy to detect mucosal dysplasia. All patients had pancolitis for at least eight years. The mean age at symptom onset was 23.2 years and the mean duration of disease at entry was 17 years. An average of 4.2 tests/patient were performed, and 91% were completely followed through 1985. Cancer risk was expressed as the hazard rate or the annual probability that a patient free of cancer would develop cancer after survival to a given time period. The hazard rate for high-grade dysplasia or cancer in patients with pancolitis measured from symptom onset was 2.5% at 20 years, 4% at 25 years, 7% at 30 years, 13% at 35 years, and 20% at 40 years. Sex was not a significant predictor of cancer, but older age at symptom onset was a predictor of dysplasia and cancer. From these data, the annual hazard rate of developing high-grade dysplasia or cancer can be estimated in patients with pancolitis based on an individual's age at symptom onset and duration of disease.

Cancer surveillance of patients with longstanding ulcerative colitis: a clinical, endoscopical, and histological study

An eight year endoscopical and histological cancer surveillance programme comprising 71 patients with ulcerative colitis is presented. Forty one patients had total colitis and 30 substantial colitis. Mean duration of the disease was 19.7 years (range 9-46 years). An average of 2.6 colonoscopies per patient in the total colitis group were carried out, and at least two biopsies were taken at 10 locations in the colon. In the total colitis group, seven had either low (four), or high grade dysplasia (two), or Dukes' A cancer (one). In the group with substantial colitis two patients with low grade dysplasia were found. Dysplasia or cancer leading to operation was found above the rectum in four of five operated patients, all having had total colitis for 25 to 44 years. The dysplasia and cancer findings at the colonoscopy preceding surgery corresponded well with the surgical specimens. In three operated patients a sequence of dysplasia development was recorded. With the exception of long duration and dysplasia, nothing in the clinical course distinguished the operated cases. Using this surveillance programme prophylactic colectomy can be limited to patients in a high risk group developing dysplasia. The risk of missing a cancer before it becomes incurable seems to be low.

Current issues in the treatment of colorectal cancer

For colorectal cancers that are confined to the bowel wall with uninvolved nodes, surgery alone is curative in most patients, and adjuvant treatment is usually not indicated. A combined modality approach for the initial treatment of many rectal and selected colonic carcinomas is based on data that "radical" operations do not necessarily prevent either local regrowth or distant failures and acceptance of a significant palliative but infrequent curative role for irradiation and chemotherapy when such failures occur. Published data for rectal cancer indicates that local recurrence can be markedly reduced by moderate to high dose pre- and post-operative irradiation +/- chemotherapy. For colon cancer, data from pilot trials suggest that post-operative irradiation may reduce local recurrence by stage when compared with surgery alone analyses, but randomized trials are needed. With locally advanced disease, aggressive treatment combinations appear to increase both local control and survival, but much interaction is required between involved physicians.

Ulcerative colitis and colonic cancer. Problems in assessing the diagnostic usefulness of mucosal dysplasia

To assess the association of mucosal dysplasia and colonic cancer in patients with ulcerative colitis and to avoid bias in biopsy interpretation that may have affected results of previous studies, the authors examined coded histology slides from colectomy specimens of 22 patients who had ulcerative colitis and colonic cancer and 22 patients who had ulcerative colitis but no colonic cancer. As expected, it was found that dysplasia occurred contiguous to each cancer. However, at a distance from the cancer (i.e., in histology blocks not containing cancer), some dysplasia was found (low or high grade) in 16/22 cases (73 percent), and high grade dysplasia in 11/22 cases (50 percent). These results suggest that there may be somewhat weaker association than previously reported between colonic cancer and dysplasia at a distance from the colonic cancer. Further, these results suggest that, in studies of dysplasia, it is important to avoid bias in biopsy interpretation and to describe sampling methods.

Large bowel mucosal dysplasia and carcinoma in ulcerative colitis

The clinicopathological details of eight cases of ulcerative colitis complicated by carcinoma of the colon are described. There was a total of 14 primary colonic cancers, six of which were not detected before pathological examination of the resection specimens. The reason for this may be related to atypical tumour growth patterns. Three occurred in flat mucosa, one in a mucosal plaque lesion, and another in polypoidal mucosa. The occurrence, distribution, and morphology of mucosal dysplasia were noted in both resection specimens and biopsies taken at varying stages before resection. Tumour was associated with normal and adjacent dysplastic mucosa of varying grades. The extent and grade of dysplasia were not reliable indicators of tumour differentiation or subsequent clinical outcome. Only two cancers were poorly differentiated. In five cases a total of 23 mucosal biopsies were taken, all less than 12 months before resection. Three rectal biopsies were graded positive for dysplasia and three colonic biopsies indefinite for dysplasia. The subsequent resection specimens showed both dysplastic and carcinomatous changes. Three rectal and 14 colonic biopsies were graded negative for dysplasia despite positive findings in the subsequent resection specimens. This anomaly is partly attributed to the patchy nature of dysplasia in colitic mucosa. Two cases illustrate the possibility of dysplasia pursuing a rapidly progressive course. The mucosal changes of ulcerative colitis were assessed using a recently introduced and standardised international classification.

Cancer surveillance in ulcerative colitis. Experience over 15 years

In the years 1966-80, 303 patients with radiologically extensive ulcerative colitis were followed up regularly, both by clinical assessment and by mucosal biopsies, to detect dysplastic (precancerous) change. Moderate or severe dysplasia (but no carcinoma) was found in the specimen in 8 patients treated surgically. Despite regular surveillance, carcinoma developed in 13 of the 186 patients with a history of disease for ten years or more. Of the total sixteen carcinomas in these 13 patients, eleven were Dukes stage A, three stage B, one stage C, and one was inoperable. There has been 1 death from carcinoma in this series over the fifteen year observation period. The method of follow-up has probably prevented the development of carcinoma in 8 patients and permitted diagnosis of carcinoma at a stage when cure is likely in 11. The incidence of moderate or severe dysplasia and carcinoma in these patients with mild or symptomless extensive colitis shows that either proctocolectomy or careful follow-up should be advised once the duration of symptoms reaches ten years.