Norwegian Colorectal Cancer Prevention Research Articles

Biopsy of Colorectal Polyps Is Not Adequate for Grading of Neoplasia

Valid tissue sampling of colorectal adenomas is crucial for their management in terms of treatment and follow-up. The aim of this study was to assess the validity of a cold biopsy sample as representative for the whole polypectomy specimen, with regard to histopathological features. As part of the Norwegian Colorectal Cancer Prevention trial, 442 participants (60% men) who fulfilled the criterion of colonoscopic recovery of adenoma that had been biopsied at flexible sigmoidoscopy, had their adenomas subsequently removed by polypectomy (snare resection) at colonoscopy. Logistic regression analysis was used to determine which variables contributed to the histopathological discrepancy between cold biopsy and polypectomy specimens. Among the 532 colorectal adenomas biopsied at flexible sigmoidoscopy and removed by colonoscopy, the assessment of intraepithelial neoplasia (dysplasia) status was changed in 51 adenomas (10%), and 38 (7%) of them had been underestimated at biopsy compared with polypectomy. Likewise, the assessment of villousness was changed in 45 adenomas (9%), being upgraded in 26 (6%) at polypectomy compared with biopsy. In a multivariate model, the diameter of neoplasia at polypectomy was positively associated with increased risk of the underestimation of intraepithelial neoplasia and/or villousness influencing a diagnosis of advanced colorectal neoplasia, when cold biopsy and polypectomy specimens were compared ( Ptrend=0.01). Among 56 cases of advanced neoplasia, 35 (63%) showed only low-grade intraepithelial neoplasia on biopsy. Biopsy-based diagnosis underestimated histopathological diagnosis in about 10% of colorectal adenomas detected by flexible sigmoidoscopy screening, but advanced neoplasia was underestimated in more than 60%. Efforts must be made to obtain polypectomy specimens to secure precise diagnosis.

Quality control in colorectal cancer screening: systematic microbiological investigation of endoscopes used in the NORCCAP (Norwegian Colorectal Cancer Prevention) trial.

BackgroundEndoscopic colorectal cancer (CRC) screening is currently implemented in many countries. Since endoscopes cannot be sterilised, the transmission of infectious agents through endoscopes has been a matter of concern. We report on a continuous quality control programme in a large-scale randomised controlled trial on flexible sigmoidoscopy screening of an average-risk population. Continuously, throughout a two-year screening period, series of microbiological samples were taken from cleaned ready-to-use endoscopes and cultured for bacterial growth.Results8573 endoscopies were performed during the trial period. Altogether, 178 microbiological samples (2%) were taken from the biopsy channels and surfaces from the endoscopes. One sample (0.5%) showed faecal contamination (Enterobacter cloacae), and 25 samples (14%) showed growth of environmental bacteria.ConclusionsGrowth of bacteria occurs in a clinical significant number of samples from ready-to-use endoscopes. Pathogenic bacteria, however, were found only in one sample. Improvement of equipment design and cleaning procedures are desirable and continuous microbiological surveillance of endoscopes used in CRC screening is recommended.

Quality control in Crc screening: Microbiological investigation of endoscopes in the NORCCAP (Norwegian colorectal cancer prevention) trial

Quality control in Crc screening: Microbiological investigation of endoscopes in the NORCCAP (Norwegian colorectal cancer prevention) trial

The Norwegian Colorectal Cancer Prevention (NORCCAP) Screening Study

Background: Randomized controlled trials of sufficient power testing the long-term effect of screening for colorectal neoplasia only exist for faecal occult blood testing (FOBT). There is indirect evidence that flexible sigmoidoscopy (FS) may have a greater yield. The aim of this study was to determine the diagnostic yield of screening with FS or a combination of FS and FOBT in an average-risk population in an urban and combined urban and rural population in Norway. Methods: 20,780 men and women (1:1), aged 50-64 years, were invited for once-only screening (FS only or a combination of FS and FOBT (1:1)) by randomization from the population registry. A positive FS was defined as a finding of any neoplasia or any polyp S 10 r mm. A positive FS or FOBT qualified for colonoscopy. Results: Overall attendance was 65%. Forty-one (0.3%) cases of CRC were detected. Any adenoma was found in 2208 (17%) participants and 545 (4.2%) had high-risk adenomas. There was no difference in diagnostic yield between the FS and the FS and FOBT group regarding CRC or high-risk adenoma. Work-up load comprised 2821 colonoscopies in 2524 (20%) screenees and 10% of screenees were recommended later colonoscopy surveillance. There were no severe complications at FS, but six perforations after therapeutic colonoscopy (1:336). Conclusions: The present study bodes well for future management of a national screening programme, provided that follow-up results reflect adequate proof of a net benefit. It is highly questionable whether the addition of once-only FOBT to FS will contribute to this effect.

Inter‐endoscopist variation in polyp and neoplasia pick‐up rates in flexible sigmoidoscopy screening for colorectal cancer

Background: The Norwegian Colorectal Cancer Prevention study is an ongoing flexible sigmoidoscopy (FS) screening trial for colorectal cancer. Twenty‐one thousand average‐risk individuals, aged 50–64 years, living in two separate areas in Norway were randomly drawn from the Population Registry and invited to once‐only screening flexible sigmoidoscopy. Examinations were performed over 3 years, at 2 centres, by 8 different endoscopists, using the same type of equipment. The aim of the present study was to investigate possible differences between endoscopists in detecting individuals with polyps, adenomas and advanced lesions (adenomas with severe dysplasia and/or villous components and/or size larger than 9 mm and carcinoma) in flexible sigmoidoscopy screening. Methods: The present trial comprises data from 8822 individuals, aged 55–64 years, who have undergone a flexible sigmoidoscopy. In the study period, all lesions detected by the different endoscopists were registered. Tissue samples were taken from all lesions detected. Results: Detection rates varied significantly between endoscopists, ranging from 36.4% to 65.5% for individuals with any polyp, from 12.7% to 21.2% for any adenoma and from 2.9% to 5.0% for advanced lesions. In a multiple logistic regression model, the performing endoscopist was a strong independent predictor for detection of individuals with polyps (P < 0.001), adenomas (P < 0.001) and advanced lesions (P = 0.01). Conclusion: Detection rates for colorectal lesions vary significantly between endoscopists in colorectal cancer screening. Establishing systems for monitoring performance in screening programmes is important. Supervised training and re‐certification for endoscopists with poor performance should be considered.

Prospects for the worldwide control of colorectal cancer through screening

Prospects for the worldwide control of colorectal cancer through screening

Design, Organization and Management of a Controlled Population Screening Study for Detection of Colorectal Neoplasia: Attendance Rates in the NORCCAP Study (Norwegian Colorectal Cancer Prevention)

Background: In the past three decades, the incidence of colorectal cancer (CRC) in Norway has doubled, surpassing all other Nordic countries for both men and women to become the most frequently diagnosed cancer. A small-scale, randomized study on flexible sigmoidoscopy (FS) screening in Telemark, Norway, has shown a reduction in accumulated CRC incidence after 13 years. The aim of our study was to evaluate the effect on CRC mortality and morbidity by screen detection of CRC and removal of precursor lesions (polypectomy), and to test out the management and organization mimicking a countrywide screening service. A total of 13,823 men and women (1:1), age 55-64 years, were drawn randomly from the population registries in Oslo (urban) and the county of Telemark (mixed urban and rural) and invited to have a screening examination. The rest of the relevant age cohorts constituted the control groups. In the screening group, 535 individuals were excluded according to exclusion criteria, rendering 13,288 individuals eligible for screening examination. Methods: A once only screening model was used. In the screening group, individuals were randomized to have a once only FS or a combination of FS and faecal occult blood test (FOBT). Results: The overall attendance rate was 8,849 out of 13,288 (67%); 73% in Telemark and 60% in Oslo. Attendance for FS only was 68% and 65% for combined FS&FOBT. Conclusions: The present FS/FS&FOBT screening study obtained a high acceptance rate for both screening modalities. The attendance rate was stable throughout the trial, suggesting an acceptable model for management of future countrywide screening.

Norwegian colorectal cancer prevention (NORCCAP): A randomized controlled trial to assess the safety and efficacy of carbon dioxide insufflation in colonoscopy

Norwegian colorectal cancer prevention (NORCCAP): A randomized controlled trial to assess the safety and efficacy of carbon dioxide insufflation in colonoscopy

Flexible sigmoidoscopy screening: A randomised, controlled study of the population in the South of Norway. The Norwegian colorectal cancer prevention study (MORCCAP)

Flexible sigmoidoscopy screening: A randomised, controlled study of the population in the South of Norway. The Norwegian colorectal cancer prevention study (MORCCAP)

Flexible sigmoidoscopy screening: A randomised, controlled study of the population in the South of Norway. The Norwegian colorectal cancer prevention study (MORCCAP)

Flexible sigmoidoscopy screening: A randomised, controlled study of the population in the South of Norway. The Norwegian colorectal cancer prevention study (MORCCAP)

Norwegian colorectal cancer prevention (NORCCAP)

Norwegian colorectal cancer prevention (NORCCAP)