Table 1. Characteristics of 41 patients carrying a pathogenic variant in SMAD4.

	Findings
No. of patients (age range) at study inclusion	41 (2–78y)
Female:male	20:21
No. of families	15
No. of patients deceased (mean age at death)	9 (54y)
Origin of gene variant: De novo;inherited;unknown	7:5:3
Gastric finding
No. of patients for which information about endoscopy was available	31
No. of patients for which detailed description and/or images of the gastric ventricle where available	29
No. of patients with at least one abnormal gastric finding	27/31 (87 %)
No. of patients with gastric polyposis (all)	21/31 (68 %)
Local polyposis	4/29 (7 %)
Diffuse polyposis	16/29 (55 %)
No. of patients who had had gastric cancer (mean age)	2/41 (42)
No. of patients who had had gastrectomy without gastric cancer (mean age at operation)	9/41 (44y)
Gastric mucosa
Edema	21/29 (72 %)
Vulnerability	15/29 (52 %)
Erythema	21/29 (72 %)
Other
Hiatal hernia	9/29 (31 %)