Analysis of 25 years of screening for colorectal neoplasia based on moderate familial risk
Authors: Macrae, F.A., Slattery, M.A., Brown, G.J., St John, D.J.B., O'Dwyer, M. and Budd, K.
Journal: Journal of Gastroenterology & Hepatology (2006); 21 (Suppl. 4): A263
Abstract:
Patients with a moderate familial risk as defined by NHMRC guidelines are offered 5 yearly colonoscopy and annual faecal occult blood testing based on age and pedigree-stratified colorectal cancer risk (CRC). Outcome information is limited.
Methods: 522 at risk members of families affected with CRC were divided into four groups: 1. Both parents affected; 2. Two siblings affected; 3. Parent and grandparent affected; 4. One first degree affected <55 years. Worst screening outcomes of cancer, advanced adenomas, other adenomas, hyperplastic polyps and other/normal were measured by gender and cumulative worst pathology by age.
Results: Percent accumulative worst pathology findings to Age (years)
| Normal | HP | Other Ad | Adv Ad | Cancer | ||
|---|---|---|---|---|---|---|
| Both Parents Age | ||||||
| (p = 75) | <40 | 61 | 11 | 28 | — | — |
| (c = 263) | 40-60 | 63 | 18 | 18 | 2 | — |
| >60 | 41 | 13 | 31 | 14 | — | |
| Parent and Grandparent | ||||||
| (p = 155) | <40 | 70 | 7 | 8 | 13 | 1 |
| (c = 371) | 40-60 | 74 | 10 | 13 | 1 | 1 |
| >60 | 43 | 13 | 32 | 12 | — | |
| Two Siblings | ||||||
| (p = 42) | <40 | — | — | — | — | — |
| (c = 129) | 40-60 | 63 | 11 | 13 | 5 | 7 |
| >60 | 45 | 16 | 24 | 12 | 2 | |
| First Degree Relatives <55 | ||||||
| (p = 249) | <40 | 79 | 12 | 8 | 1 | — |
| (c = 509) | 40-60 | 67 | 11 | 12 | 8 | 1 |
| >60 | 65 | 14 | 6 | 9 | 5 | |
p is the number of patients; c is number of colonoscopies
Conclusion: Despite colonoscopic surveillance and polypectomy; the proportion of high risk subjects with neoplastic findings increases with age. Those with a single first degree relative with CRC are less likely (21% [95% CI 14-28%]) than other risk groups to have adenomas at >60 years (group 1 46% [95% CI 40-52%]; group 2 38% [95% CI 28-48%]; group 3 44% [95% CI 39-49%]) but advanced adenomas were similar. Further studies will address high risk families and determine Dukes’ staging, comparison with average risk populations and merging of similar databases.
© 2006 Journal of Gastrolenterology and Hepatology Foundation and Blackwell Publishing Asia Pty Ltd