Table 1.

 Patient demographics and hyperplastic polyp characteristics

Patients
Total patients	126
Sex
Female	42 (33%)
Male	84 (67%)
Mean (SD) age at first HP	63.7 years (10.8)
No of HPs/patient
1	109 (87%)
2	14 (11%)
3	2 (1.6%)
4	1 (0.8%)
Mean (SD) number HP/patient	1.17 (0.5)
HP location by patient
Left side only	89 (71%)
Right side only	32 (25%)
Both sides	4 (3%)
Unknown	1 (0.8%)
Hyperplastic polyps
Total number	147
Left colon	109 (74%)
Right colon	37 (25%)
Unknown site	1 (0.7%)
Number with K-ras mutation	15 of 143 assayed (10%)
Location of HPs with K-ras mutation
Rectum	5
Sigmoid	10
Size of HP
15 HPs with K-ras mutation	3.2 mm
128 HPs without K-ras mutation	3.25 mm
Number with APC LOH	0 of 133 assayed
Number with MSI	0 of 55 assayed
HP in same segment
As an adenoma*
Yes	68 (48%)
No	73 (52%)

*1 patient had HP of unknown location, 4 had carcinoma and no adenoma, 1 had small bowel carcinoma.

APC, adenomatous polyposis coli; HP, hyperplastic polyp; LOH, loss of heterozygosity; MSI, microsatellite instability.