IGF2 differentially methylated region hypomethylation in relation to pathological and molecular features of serrated lesions

Table 1 IGF2 differentially methylated region 0 hypomethylation in serrated lesions and non-serrated adenomas n (%)

Clinicopathological feature	Total n	IGF2 DMR0 methylation (quartile)				P value
		Q1 (≥74.5)	Q2 (62.6-74.4)	Q3 (49.6-62.5)	Q4 ( ≤49.5)
All cases	536	134	130	131	141
Sex
Male	326 (61)	78 (58)	80 (62)	92 (70)	76 (54)	0.041
Female	210 (39)	56 (42)	50 (38)	39 (30)	65 (46)
Age (mean ± SD)	61.5 ± 12.2	59.9 ± 12.3	60.8 ± 12.0	63.1 ± 11.6	62.3 ± 13.0	0.150
Tumor size (mm) (mean ± SD)	14.3 ± 11.4	9.9 ± 4.0	13.4 ± 7.4	14.7 ± 11.1	19.1 ± 17.6	< 0.0001
Tumor location
Rectum	70 (13)	11 (8.5)	14 (11)	18 (14)	27 (20)	0.061
Distal colon	161 (31)	35 (27)	43 (33)	37 (29)	46 (33)
Proximal colon	296 (56)	84 (65)	72 (56)	75 (58)	65 (47)
Histological type
Hyperplastic polyp (HP)	115 (21)	33 (25)	25 (19)	23 (18)	34 (24)	< 0.0001
Sessile serrated adenoma (SSA) without cytological dysplasia	120 (22)	60 (45)	39 (30)	15 (11)	6 (4.3)
SSA with cytological dysplasia	10 (1.9)	1 (0.8)	3 (2.3)	6 (4.6)	0 (0)
Traditional serrated adenoma (TSA) without high-grade dysplasia (HGD)	91 (17)	22 (16)	21 (16)	23 (18)	25 (18)
TSA with HGD	15 (2.8)	2 (1.5)	2 (1.5)	2 (1.5)	9 (6.4)
Non-serrated adenoma (tubular or tubulovillous adenoma) without HGD	80 (15)	11 (8.2)	17 (13)	32 (24)	20 (14)
Non-serrated adenoma with HGD	105 (20)	5 (3.7)	23 (18)	30 (23)	47 (33)

Percentage indicates the proportion of patients of each histological type who met the criteria for a specific clinical or molecular feature. P values were calculated by analysis of variance for age and tumor size and by χ² or Fisher’s exact test for all other variables. The P value for significance was adjusted by Bonferroni correction to 0.010 (= 0.05/5).