Table 2.
Colonoscopic findings (most neoplastic lesion for each individual) at initial surveillance colonoscopy by family risk group and age. Values are numbers (percentages) of patients
| Risk group by age | Normal finding | Metaplastic polyp | Simple adenoma | Multiple simple adenomas | High risk adenoma | Cancer |
|---|---|---|---|---|---|---|
| Group 4 (Amsterdam criteria): | ||||||
| 20-34 (n=213) | 176 (83.2) | 13 (5.9) | 14 (6.4) | 2 (0.9) | 6 (2.7) | 2 (0.9) |
| 35-44 (n=158) | 115 (72.8) | 10 (6.3) | 23 (14.5) | 1 (0.6) | 8 (5.1) | 1 (0.6) |
| 45-64 (n=164) | 89 (53.8) | 26 (16.0) | 31 (19.1) | 5 (3.1) | 12 (7.4) | 1 (0.6) |
| ≥65 (n=19) | 11 (55.8) | 1 (5.5) | 3 (16.6) | 0 (0.0) | 3 (17.0) | 1 (5.1) |
| Overall*
|
391 (68.7)
|
50 (9.3)
|
79 (15.4)
|
34 (6.6)
|
||
| Group 3†: | ||||||
| 20-34 (n=68) | 65 (95.4) | 1 (1.5) | 2 (3.1) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| 35-44 (n=109) | 83 (76.5) | 10 (9.0) | 15 (13.6) | 0 (0.0) | 1 (0.9) | 0 (0.0) |
| 45-64 (n=190) | 112 (57.9) | 15 (8.1) | 48 (25.9) | 6 (3.2) | 9 (4.9) | 0 (0.0) |
| ≥65 (n=24) | 13 (54.2) | 4 (16.6) | 0 (0.0) | 2 (8.3) | 4 (16.6) | 1 (4.2) |
| Overall*
|
273 (72.9)
|
30 (7.2)
|
73 (16.5)
|
15 (3.3)
|
||
| Group 2†: | ||||||
| 20-34 (n=145) | 118 (82.4) | 14 (9.1) | 11 (7.2) | 0 (0.0) | 2 (1.3) | 0 (0.0) |
| 35-44 (n=171) | 136 (79.6) | 11 (6.4) | 20 (11.7) | 1 (0.6) | 3 (1.8) | 0 (0.0) |
| 45-64 (n=201) | 144 (72.1) | 18 (8.8) | 26 (12.7) | 5 (2.5) | 8 (3.9) | 0 (0.0) |
| ≥65 (n=19) | 6 (33.3) | 4 (20.5) | 7 (35.9) | 1 (5.3) | 1 (5.0) | 0 (0.0) |
| Overall*
|
404 (76.2)
|
47 (8.5)
|
71 (12.8)
|
14 (2.5)
|
||
| Group 1†: | ||||||
| 20-34 (n=82) | 72 (86.3) | 8 (11.0) | 2 (2.7) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| 35-44 (n=57) | 51 (90.0) | 3 (5.0) | 2 (3.3) | 0 (0.0) | 1 (1.7) | 0 (0.0) |
| 45-64 (n=53) | 40 (74.4) | 5 (9.9) | 8 (15.7) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| ≥65 (n=5) | 3 (57.1) | 1 (22.0) | 0 (0.0) | 1 (20.9) | 0 (0.0) | 0 (0.0) |
| Overall* | 166 (81.8) | 17 (9.8) | 13 (7.8) | 1 (0.6) | ||
Group 2 includes families with two affected first degree relatives, or one first degree and one second degree relative, who are first degree relatives of each other. Group 1 includes families in which colorectal cancer has been diagnosed in one first degree relative under age 45, with no other cases.
Percentages may not correspond with the absolute numbers because of standardisation.
Standardised by age.
Group 3 includes families with colorectal cancer in at least three individuals affected over two generations, one a first degree relative of the other two, but no cases diagnosed under age 50.