Table 1.

Baseline characteristics of the patients

Clinical features	Number of patients
Gender (male : female)	156 : 147
Age at diagnosis (range)	32.4 (10–75)
Colonic phenotype (classical FAP : AFAP)	265 : 38
Fundic gland polyp (present : absent)	114 : 113 (50.2%)
Gastric adenoma (present : absent)	33 : 192 (14.7%)
Gastric cancer (present : absent)	11 : 250 (4.2%)
Duodenal adenoma (present : absent)	72 : 155 (31.7%)
Duodenal cancer (present : absent)	7 : 247 (2.8%)

FAP, familial adenomatous polyposis; AFAP, attenuated familial adenomatous polyposis.