Table 2.
Cohort characteristics by study group
| Lynch Syndrome | Non-Lynch group | ||||
|---|---|---|---|---|---|
| n | % | n | % | p | |
| Total cohort | 112 | 100.0 | 908 | 100.0 | |
| Colon CFR centera | <0.001 | ||||
| Ontario | 8 | 7.1 | 234 | 25.8 | |
| Los Angeles | 17 | 15.2 | 94 | 10.4 | |
| Australia | 59 | 52.7 | 139 | 15.3 | |
| Hawaii | 4 | 3.6 | 31 | 3.4 | |
| Mayo Foundation | 21 | 18.8 | 142 | 15.6 | |
| Seattle | 3 | 2.7 | 268 | 29.5 | |
| Ascertainment type | <0.001 | ||||
| Population-based | 33 | 29.5 | 829 | 91.3 | |
| Clinic-based | 79 | 70.5 | 79 | 8.7 | |
| Age at first colorectal cancer diagnosis | <0.001 | ||||
| 15–39 years | 57 | 50.9 | 102 | 11.2 | |
| 40–49 years | 36 | 32.1 | 232 | 25.6 | |
| 50–59 years | 14 | 12.5 | 230 | 25.3 | |
| 60 years and over | 5 | 4.5 | 344 | 37.9 | |
| Median age at first colorectal cancer diagnosis | 39 years (IQR = 34 yrs –45 yrs) | 54 years (IQR = 46 yrs – 65 yrs) | <0.001 | ||
| Number of other cancer diagnoses | <0.001 | ||||
| None | 77 | 68.8 | 781 | 86.0 | |
| One | 20 | 17.9 | 103 | 11.4 | |
| Two or more | 15 | 13.4 | 24 | 2.6 | |
| Timing of other cancer diagnosesb | |||||
| Prior to first colorectal cancer | |||||
| Ovarian cancer | 0 | 0.0 | 4 | 0.3 | 1.000 |
| Other cancer (excluding endometrial) | 2 | 1.8 | 68 | 7.5 | 0.040 |
| Subsequent to first colorectal cancer | |||||
| Endometrial cancer | 22 | 19.6 | 8 | 0.9 | <0.001 |
| Ovarian cancer | 2 | 1.8 | 3 | 0.3 | 0.096 |
| Other cancers | 19c | 17.0 | 53 | 5.8 | <0.001 |
| Procedures/Medicationb | |||||
| Hysterectomy | 50 | 44.6 | 37 | 4.1 | <0.001 |
| Tamoxifen | 1 | 0.9 | 15 | 1.7 | 0.836 |
| Median follow-up after initial colorectal cancer diagnosis | 10.7 years (IQR = 6.1 yrs–23.1 yrs) | 6.1 years (IQR = 4.9 yrs–6.9 yrs) | <0.001 | ||
| Median time at risk for endometrial cancer | 6.3 years (IQR = 3.7 yrs–12.3 yrs) | 6.0 years (IQR = 4.4 yrs–6.8 yrs) | 0.011 | ||
IQR = inter-quartile range
Ontario (Cancer Care Ontario, recruitment from Ontario, Canda), Los Angeles (University of Southern California consortium, recruitment from Los Angeles County, California; Cleveland, Ohio; Arizona; Colorado; New Hampshire; and parts of North Carolina), Australasia (University of Melbourne, recruitment from Victoria, New South Wales, South Australia and Western Australia, Australia, and Auckland, New Zealand), Hawaii (University of Hawaii, recruitment from Hawaii), Mayo Clinic (Mayo Clinic, recruitment from Rochester, Minnesota), Seattle (Fred Hutchinson Cancer Research Centre, recruitment from Puget Sound are, Washington).
Categories do not add to total cohort
Other cancers diagnosed in the Lynch group include 7 melanomas, 3 breast cancers, 3 kidney cancers, 2 cancers of the vulva, 2 bladder cancers, 1 stomach cancer, 1 cancer of the small intestine, 1 liver cancer, 1 lung cancer and 1 cancer of other female genital organs (NOS).