At what age do patients no longer need colorectal cancer screening?

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Clinical Inquiries

At what age do patients no longer need colorectal cancer screening?

J Fam Pract. 2001 July;50(7):575-576

By

Paul Tatum, MD

David Mehr, MD, MSPH

References

1. Towler BP, Irwig L, Glasziou P, Weller D, Kewenter J. Screening for colorectal cancer using the fecal occult blood test, Hemoccult (Cochrane Review). The Cochrane Library. Oxford, UK: Update Software; 2001.

2. Kronborg O, Fenger C, Olsen J, Jorgensen OD, Sondergaard O. Randomised study of screening for colorectal cancer with fecal occult blood test. Lancet 1996;348:1467-71.

3. Kewenter J, Brevinge H, Engaras B, Haglind E, Ahren C. Results of screening, rescreening, and follow-up in a prospective randomized study for detection of colorectal cancer by fecal occult blood testing. Results for 68,308 subjects. Scand J Gastroenterol. 1994;29:468-73.

4. Hardcastle JD, Chamberlain JO, Robinson MH, et al. Randomised controlled trial of fecal-occult-blood screening for colorectal cancer. Lancet 1996;348:1472-77.

5. Mandel JS, Bond JH, Church TR, et al. Reducing mortality from colorectal cancer by screening for fecal occult blood. Minnesota Colon Cancer Control Study. N Engl J Med 1993;328:1365-71.

6. Lazovich D, Weiss NS, Stevens NG, White E, McKnight B, Wagner EH. A case-control study to evaluate efficacy of screening for fecal occult blood. J Med Screen 1995;2:84-9.

7. Newcomb PA, Norfleet RG, Storer BE, Surawicz TS, Marcus PM. Screening sigmoidoscopy and colorectal cancer mortality. J Natl Cancer Inst 1992;84:1572-75.

8. Muller AD, Sonnenberg A. Protection by endoscopy against death from colorectal cancer. A case-control study among veterans. Arch Intern Med 1995;155:1741-48.

9. Selby JV, Friedman GD, Quesenberry CP, Jr, Weiss NS. A case-control study of screening sigmoidoscopy and mortality from colorectal cancer. N Engl J Med 1992;326:653-57.

10. Scholefield JH. ABC of colorectal cancer—screening. BMJ 2000;321:1004-06.

11. Rex DK, Lehman GA, Ulbright TM, Smith JJ, Hawes RH. The yield of a second screening flexible sigmoidoscopy in average-risk persons after one negative examination. Gastroenterology 1994;106:593-95.

12. Atkin WS, Morson BC, Cuzick J. Long-term risk of colorectal cancer after excision of rectosigmoid adenomas. N Engl J Med 1992;326:658-62.

13. Mulcahy HE, Farthing MJ, O’Donoghue DP. Screening for asymptomatic colorectal cancer. BMJ 1997;314:285-91.

14. Anderson RN. United States life tables, 1997. National Vital Statistics Reports 1999;47:1-37.

15. Anderson ML, Pasha TM, Leighton JA. Endoscopic perforation of the colon: lessons from a 10 year study. Am J Gastroenterol 2000;95:3418-22.

16. US Preventive Services Task Force Screening for colorectal cancer. Guide to clinical preventive services: report of the US Preventive Services Task Force. Baltimore, MD: Williams & Wilkins; 1996;89-103.

17. Periodic health examinations: summary of AAFP policy recommendations and age charts Positive recommendations: general population standards. Last updated 2000. Accessed on 12-6-2000.

18. Winawer SJ, Flehinger BJ, Schottenfeld D, Miller DG. Screening for colorectal cancer with fecal occult blood testing and sigmoidoscopy. J Natl Cancer Inst 1993;85:1311-18.

19. Byers T, Levin B, Rothenberger D, Dodd GD, Smith RA. American Cancer Society guidelines for screening and surveillance for early detection of colorectal polyps and cancer: update 1997. American Cancer Society Detection and Treatment Advisory Group on Colorectal Cancer. CA Cancer J Clin 1997;47:154-160.

20. Colorectal Cancer Screening: Clinical Guidelines and Rationale. Gastroenterology 1997;112:594-642.

21. Colon cancer screening (USPSTF recommendation). US Preventive Services Task Force. J Am Geriatr Soc 2000;48:333-35.

EVIDENCE-BASED ANSWER

Good evidence supports fecal occult blood testing (FOBT) for patients up to age 75 (grade of recommendation: A, based on systematic review of randomized controlled trials). There is insufficient evidence to recommend for or against colorectal cancer (CRC) screening after age 75 (grade of recommendation: D, based on expert opinion). CRC screening may be discontinued between ages 75 and 80, preferably after at least 1 negative screening examination result. Unusually healthy individuals may choose to continue screening until a later age.

Evidence summary

FOBT is the only CRC screening tool with evidence of efficacy from randomized controlled trials.¹ A meta-analysis of 4 trials showed that 1173 patients would need to be screened for 10 years on a biennial basis to prevent 1 death from CRC. The upper age limits of patients were 75,² 64,³ 74,⁴ and 80 years.⁵ In the one study that included subjects to age 80, only 13% were older than 70 years. One case control study of FOBT showed a significant reduction in risk of mortality from CRC for individuals younger than 75 years, but not for patients older than 75; however, confidence intervals were wide.⁶

Evidence for screening with flexible sigmoidoscopy and colonoscopy comes primarily from case-control studies, and little information about appropriate upperage limits is available.^7-9 However, average time from onset of polyp to carcinoma is 10 to 15 years.¹⁰ Furthermore, cancers, large polyps (>1 cm), or dysplastic polyps were not found in any patient examined a mean of 3.4 years after normal flexible sigmoidoscopy,¹¹ and subsequent cancer is a rare early event after endoscopy, even in patients who have had polyps removed.¹² This suggests the cessation of endoscopic screening would miss few cancers in the very old.

While CRC incidence approximately doubles with each decade from age 40 to 80,¹³ the average life expectancy is 11.2 years at age 75 and 8.5 years at age 80.¹⁴ Given the slow progression from polyp to carcinoma, such patients may not live long enough to achieve any screening benefits. Similar reasoning suggests that even high-risk patients (eg, those with a family history of CRC) with repeatedly normal endoscopic examination results may be able to discontinue screening between ages 75 and 80, unless they are unusually healthy.

Risks of screening include discomfort from endoscopic examinations and complications relating to the many false-positive results of FOBT (98% in Minnesota study).⁵ A meta-analysis found that patients experience 1 perforation or hemorrhage for every 2.5 to 4.7 lives saved.¹ The risk of death is only about 1 in 50,000 for colonoscopy at the Mayo Clinic.¹⁵ Other complications include worry, perforation, and complications of treatment.

Recommendations from others

The USPSTF, AAFP, American Gastroenterology Association, and the American Cancer Society recommend screening adults 50 years of age and older for colon cancer; none sets an upper limit.^16-20 The USPSTF specifically states, “the appropriate age to discontinue screening has not been determined.”¹⁶ The American Geriatrics Society recommends that patients with short life expectancy or patients who could not undergo colonoscopy or barium enema plus sigmoidoscopy should not be screened.²¹

CLINICAL COMMENTARY

Brian Easton, MD
Highlands Family Medicine Lebanon, Virginia

Knowing the average time from onset of polyp to carcinoma and the life expectancy at 75 and 80 years old is very helpful. This gives support to using endoscopy in addition to FOBT instead of FOBT alone, especially during the period before the cessation of routine screening. A negative sigmoidoscopy result would “insure” the next 3 to 5 years and colonoscopy the next 10 years. After explaining the benefits of screening, I tell my patients that when they complete a FOBT each year, they have a 10% to 40% chance of having a colonoscopy, and if they have this follow-up procedure, they have a 0.3% or less chance of having a perforation or hemorrhage as a complication.^1-5 Most of my patients older than 75 years choose not to continue screening.

Evidence-based answers from the Family Physicians Inquiries Network