Colonoscopy in patients with a family history of colorectal cancer

The BSG/ACPGBI guidelines for colonoscopic screening: what are we missing?

INTRODUCTION

Before publication of the British Society of Gastroenterology and Association of Coloproctology of Great Britain and Ireland guidelines in 2002, screening for people with a family history of colorectal cancer was sporadic and largely dependant on unvalidated local guidelines. Since 1990 we have been screening patients with both high and moderate risk family histories of colorectal cancer using local protocols which were more liberal than the new guidelines. In this study, we have analysed the pathology that would have been missed if we had been using the new guidelines in the period 1990-2002.

METHOD

A total of 399 consecutive patients with a positive family history of colorectal malignancy underwent screening endoscopy according to local guidelines. Demographic, endoscopic and pathologic data were prospectively collected. Patients were retrospectively divided into those who would have been screened under the new guidelines (group 1) and those who would not (group 2). The recorded pathology was graded as significant or insignificant and the findings compared between the two groups.

RESULTS

A total of 399 patients underwent 557 endoscopies of which 278 (50%) were indicated under the new guidelines (group 1) and 279 (50%) were not indicated (group 2). A significant pathology or carcinoma was found in 15.8% of group 1 endoscopies and 10.0% of group 2 endoscopies. This difference was significant.

CONCLUSION

If we had been using the new guidelines in the period 1990-2002, we would not have performed 279 (50%) of the 557 procedures, but would not have discovered significant pathology in 10% of the moderate risk endoscopies representing 39% of the significant pathology, which was actually present in this population.

Colonoscopy in asymptomatic individuals with a family history of colorectal cancer

BACKGROUND

This study was performed to evaluate the use of total colonoscopy as the optimal screening test in asymptomatic individuals with a family history of colorectal cancer (CRC).

METHODS

Colonoscopy was performed in 249 asymptomatic individuals who had one or two first-degree relatives (FDRs) with CRC; individuals with three or more FDRs with CRC were excluded.

RESULTS

Eighty-six colonic lesions were found in 51 individuals (51 of 249; 20.5%). Among these 51 subjects, 27 had neoplastic polyps (n = 38) and 29 had metaplastic polyps (n = 44). Although no invasive cancer was detected, in 14 individuals the lesions had a high malignancy potential because of their size and histopathology. We did not confirm a statistically significant difference in the incidence of neoplastic polyps according to the number of affected FDRs. Finally, the presence of metaplastic polyps was a very strong indication for the concomitant presence of metaplastic polyps (P <.0001).

CONCLUSIONS

Total colonoscopy is the optimal screening procedure for the examination of asymptomatic individuals with a family history of CRC.

Yield from colonoscopic screening in people with a strong family history of common colorectal cancer

BACKGROUND AND AIMS

People with a strong family history of common (so-called 'sporadic') colorectal cancer are generally advised to undergo colonoscopic screening, but the starting age for this is unclear. An audit was performed to study the age-related yield of screening colonoscopy in this risk group.

METHODS

A prospective audit of the outcome of screening colonoscopy was performed on a cohort of 232 people with a strong family history of common colorectal cancer. All were registrants in a familial bowel cancer service solely because of their family medical history. They had no bowel symptoms and no prior endoscopic investigation of the large bowel.

RESULTS

Neoplastic lesions were detected by using colonoscopy in 33 participants. In 27 participants, the major lesion was a small tubular adenoma, four had an advanced adenoma and two had cancer. More neoplastic (P= 0.02) and advanced neoplastic (P= 0.03) lesions were found in those patients aged > or = 50 years. Only one advanced adenoma was detected in a participant below the age of 50 years.

CONCLUSION

The yield from screening colonoscopy in young people (< 50 years) with a strong family history of common colorectal cancer is low, placing doubt on the need for colonoscopic screening before the age of 50 years.

Results of a pilot study of endoscopic screening of first degree relatives of colorectal cancer patients in Italy

STUDY OBJECTIVE

Screening recommendations for colorectal cancer include sigmoidoscopy in asymptomatic, average risk persons aged 50 and over and colonoscopy every three to five years in high risk groups. Little is known about the eligible population's compliance with endoscopic screening. This is the first Italian report of an endoscopic screening programme for colorectal cancer patients' relatives.

DESIGN

In 1986, a pilot project for colorectal cancer screening by endoscopy in high risk subjects was started in the Desio (Milan, Italy) public health service region. The results obtained after seven years are described.

SETTING

The names of 536 inhabitants with colorectal cancer diagnosed between January 1975 and December 1984 and their relatives' addresses were obtained from the Regione Lombardia Health System records and from the municipal registry offices respectively.

PARTICIPANTS

From October 1986 to October 1993, 778 first degree relatives aged 20-75 were offered colonoscopy.

MAIN RESULTS

After seven years, 233 (29.9%) had undergone endoscopic examination, mostly up to the splenic flexure. Being > 60 in age at the start of the programme negatively affected the participation (p < 0.05). Two cancers were detected and adenomatous polyps were found in another 24 of those screened (frequencies 0.9% and 10.3% respectively). Male gender (p < 0.05), increasing age in males (p < 0.01), and two or more affected relatives in females (p < 0.01) positively affected the frequency of polyps detection.

CONCLUSION

These results suggest that about 30% of the eligible population would comply at least with sigmoidoscopic screening. The collaboration of family doctors and more widespread public information about the ability to cure colorectal cancer are necessary for better compliance.

The role of colonoscopy in screening persons with family history of colorectal cancer

First-degree relatives of colorectal cancer patients are at increased risk for developing colorectal neoplasms. In order to assess the potentiality of colonoscopy screening in this high-risk population, 213 asymptomatic family members (age range 30-69 years, mean 42.8 years) of those patients with colorectal cancer received colonoscopic examination at Chang-Gung Memorial Hospital from April 1992 to May 1994. Twenty-eight persons with 42 lesions (polyps or cancer) were identified, including 28 adenomas, nine hyperplastic polyps and five adenocarcinomas. The positive detection rate was 9.9% for adenoma and 2.3% for cancer. Colorectal neoplasms afflicted males more frequently than females (16.7 vs 5.7%, P < 0.05) and occurred less frequently in those < 40 years of age (5.5 vs 17.2%, P < 0.05). Forty-two per cent of the detected neoplastic lesions were beyond the reach of 60 cm flexible sigmoidoscopy and 36% of adenomas were < 0.5 cm in size and would be missed if patients were screened by air contrast barium enema. Cost analysis revealed that the charges of both screening colonoscopy and screening flexible sigmoidoscopy/air contrast barium enema were approximate. Colonoscopy also has a high acceptability and safety. It appears appropriate to use colonoscopy, rather than flexible sigmoidoscopy or air contrast barium enema, as an initial screening procedure for persons with a family history of colorectal cancer, especially those > 40 years of age.

Should relatives of patients with colorectal cancer be screened? A critical review of the literature

PURPOSE

The objective of our investigation was to attempt to address the controversial issue concerning index screening and surveillance of relatives of patients with colorectal cancer and to identify those areas of research that should be considered in future studies.

METHODS

Relevant literature was reviewed concerning the screening of asymptomatic first-degree relatives of patients with colorectal cancer not associated with the rare autosomal dominant inherited colorectal cancer syndromes.

RESULTS

The data reviewed suggest that there is an increased risk of colorectal neoplasia in this population and a significantly higher yield of adenomas and carcinomas when colonoscopy is used for index screening. However, significant variability in study design and screening protocols and inconsistencies in data presentation make clinical interpretation and data analysis confusing and difficult.

CONCLUSIONS

There is a critical need for standardization in future studies. Furthermore, as there are no studies that document decreased overall mortality from colorectal cancer in first-degree relatives as a result of screening, the decision as to whether to screen this population needs to be based on future prospective controlled trials.

Hereditary nonpolyposis colorectal carcinoma (HNPCC): clinical application of molecular diagnostic testing

An increased risk of colorectal cancer amongst close relatives of afflicted patients has been recognized for some time. Hereditary nonpolyposis colorectal cancer (HNPCC) represents an extreme example of this risk, in which single-gene inheritance predisposes relatives of affected family members. Approaches to surveillance and management of subjects at greater or lesser heritable risk have been evolving in the past two decades, but these efforts have suffered due to our inability to better characterize and quantify that risk. Recent discovery of susceptibility loci that are linked to disease in HNPCC has already begun to refine our understanding of the pathogenesis of the disease. At a clinical level, these advances now offer an improved ability to recognize carriers of the condition. Speculation is provided as to the probable utility of genetic testing in groups with varying strengths of colorectal cancer familiality. Notions of how positive and negative tests might be applied to surveillance and treatment are explored.