Comparing different strategies for colorectal cancer screening in Italy: predictors of patients' participation.

OBJECTIVES: The objective of this study was to study predictors of patients' participation in colorectal cancer (CRC) screening. METHODS: Men and women, aged 55-64 years, were randomized to the following: (i) biennial fecal occult blood test (FOBT) delivered by mail (n=2,266); (ii) FOBT delivered by a general practitioner (GP)/screening facility (n=5,893); (iii) "once-only" sigmoidoscopy (FS) (n=3,650); (iv) FS followed by FOBT for screenees with negative FS (n=10,867); and (v) patient's choice between FS and FOBT (n=3,579). A stratified (by screening arm) random sample of attenders and nonattenders was contacted by trained interviewers 4 months after the initial invitation. Subjects giving their consent were administered a questionnaire (available online) investigating perceptions of individual CRC risk, attitudes toward prevention, adoption of health protective behaviors, and reasons for attendance/nonattendance. Adjusted prevalence odds ratios (ORs) were computed by multivariable logistic regression. RESULTS: The response rate was 71.9% (701 of 975) among nonattenders and 88.9% (773 of 870) among attenders. Adjusting for screening arm, center, gender, age, and education, participation was significantly higher among people who consulted their GP before undergoing screening (OR: 4.24; 95% confidence interval (CI): 3.11-5.78), who mentioned one first-degree relative with CRC (OR: 3.62; 95% CI: 2.02-6.49), who reported regular physical activity (OR: 1.85; 95% CI: 1.33-2.55), and who read the mailed information (letter only: OR: 1.85; 95% CI: 1.23-2.78; letter+leaflet: OR: 3.18; 95% CI: 2.12-4.76). People who considered screening to be ineffective (OR: 0.12; 95% CI: 0.08-0.19), those who considered it to be effective but reported even moderate levels of anxiety (OR: 0.32; 95% CI: 0.23-0.45), and those who mentioned previous knowledge of CRC screening tests were less likely to accept the invitation (OR: 0.49; 95% CI: 0.34-0.70). CONCLUSIONS: Adoption of health protective behaviors is associated with a higher attendance rate, whereas anxiety represents a strong barrier, even among people who deemed screening to be effective. Increasing the proportion of people who consult their GP when making a decision regarding screening might enhance participation.

History of negative colorectal endoscopy and risk of rectosigmoid neoplasms at screening flexible sigmoidoscopy.

BACKGROUND AND AIMS: Screening sigmoidoscopy can reduce incidence of colorectal cancer and mortality. The optimal re-screening interval has not yet been defined. This study is aimed at estimating the risk of distal advanced adenomas (diameter >/=10 mm, villous component >20%, high-grade dysplasia) and cancer at screening flexible sigmoidoscopy in subjects aged 55-64 years who reported pre-screening negative colorectal endoscopy. PATIENTS: Eight thousands two hundred two subjects aged 55-64 years who underwent screening flexible sigmoidoscopy within the SCORE trial in Italy and who were able to report their previous history of colorectal endoscopy. RESULTS: Eight hundred eighty three of 8,202 subjects (10.8%) reported at least one prescreening negative endoscopy: among them, after 3-5 years, 6-10 years and >10 years intervals between last reported examination and screening endoscopy, the Absolute Risk of advanced adenomas was 1.5%, 0.9% and 0.9%; one cancer was detected (0.1%). Among the 7,319 subjects who did not report prescreening endoscopy the risks of advanced adenoma and cancer were 3.2% and 0.4%, respectively. Subjects with a previous colorectal examination had a 65% decreased risk of advanced adenomas (OR=0.35, 95%CI 0.18-0.66) and a 71% decreased risk of cancer (OR=0.29, 95%CI 0.04-1.12) as compared to those who did not. For subjects without family history of colorectal cancer the statistically significant decrease of the risk persisted up to ten years. The observed benefit seems not to apply to subjects with family history of colorectal cancer. CONCLUSIONS: Our results are consistent with the hypothesis that the interval between screening sigmoidoscopies could be safely expanded beyond 5 years for subjects without specific risk factors for colorectal cancer.

Randomized trial of different screening strategies for colorectal cancer: patient response and detection rates.

BACKGROUND: Although there is general consensus concerning the efficacy of colorectal cancer screening, there is a lack of agreement about which routine screening strategy should be adopted. We compared the participation and detection rates achievable through different strategies of colorectal cancer screening. METHODS: From November 1999 through June 2001 we conducted a multicenter, randomized trial in Italy among a sample of 55-64 year olds in the general population who had an average risk of colorectal cancer. People with previous colorectal cancer, adenomas, inflammatory bowel disease, a recent (< or =2 years) colorectal endoscopy or fecal occult blood test (FOBT), or two first-degree relatives with colorectal cancer were excluded. Eligible subjects were randomly assigned, within the roster of their general practitioner, to 1) biennial FOBT (delivered by mail), 2) biennial FOBT (delivered by general practitioner or a screening facility), 3) patient's choice of FOBT or "once-only" sigmoidoscopy, 4) "once-only" sigmoidoscopy, or 5) sigmoidoscopy followed by biennial FOBT. An immunologic FOBT was used. Participation and detection rates of the strategies tested were compared using multivariable logistic regression models that adjusted for age, sex, and screening center. All statistical tests were two-sided. RESULTS: Of 28 319 people sampled, 1637 were excluded and 26 682 were randomly assigned to a screening arm. After excluding undelivered letters (n = 427), the participation rates for groups 1, 2, 3, 4, and 5 were 30.1% (682/2266), 28.1% (1654/5893), 27.1% (970/3579), 28.1% (1026/3650), and 28.1% (3049/10 867), respectively. Of the 2858 subjects screened by FOBT, 122 (4.3%) had a positive test result, 10 (3.5 per 1000) had colorectal cancer, and 39 (1.4%) had an advanced adenoma. Among the 4466 subjects screened by sigmoidoscopy, 341 (7.6%) were referred for colonoscopy, 18 (4 per 1000) had colorectal cancer, and 229 (5.1%) harbored an advanced adenoma. CONCLUSIONS: The participation rates were similar for sigmoidoscopy and FOBT. The detection rate for advanced neoplasia was three times higher following screening by sigmoidoscopy than by FOBT.

Predicting proximal advanced neoplasms at screening sigmoidoscopy.

PURPOSE: This study was designed to assess the predictive value for advanced proximal neoplasms (cancer, adenoma > or = 10 mm, or villous component > 20 percent, or severe dysplasia) of the characteristics of distal polyps. METHODS: The study was conducted among patients, aged 55 to 64 years, referred for colonoscopy in the Italian trial of sigmoidoscopy screening for colorectal cancer. Patients reporting a history of colorectal cancer, adenomas, inflammatory bowel disease, recent colorectal endoscopy, or two first-degree relatives with colorectal cancer were excluded. We compared the prevalence of advanced proximal neoplasia in patients with "low-risk" (1-2 tubular adenomas, < 10 mm, with low-grade dysplasia, or hyperplastic polyp) and in those with "high-risk" (size, > or = 10 mm, or > or = 3 adenomas, or villous component > 20 percent, or severe dysplasia) polyps in the distal colon. RESULTS: Of 426 patients with polyps > 5 mm, 29 (6.9 percent) were detected with an advanced proximal neoplasm (including 4 colorectal cancers). The prevalence of proximal advanced neoplasia was 9.4 percent among patients with high-risk distal polyps and 2.5 percent among those with low-risk lesions (adjusted odds ratio, 3.19; 95 percent confidence interval, 1.06-9.59). Approximately 40 people with low-risk distal polyps 6 to 9 mm should undergo colonoscopy to detect one proximal advanced neoplasm; the corresponding number for patients with high-risk distal polyps is 10. CONCLUSIONS: The 2.5 percent prevalence of proximal advanced neoplasms among people with low-risk 6-mm to 9-mm distal polyps is similar to the prevalence observed among people without distal polyps. Restricting colonoscopy referral to patients with high-risk distal polyps might represent a cost-effective strategy in a screening context.