Endoscopic mucosal resection of colorectal adenomas > 20 mm: Risk factors for recurrence

Table 1 Characteristics of the resected lesions n (%)

No. of polyps	n = 216
Size (median/range)	30 mm (20.0-70.0)
Localization
Right-sided colon (cecum, ascending, transverse)	149 (69.0)
Left-sided colon (descending, sigmoid) or rectum	67 (31.0)
Morphology of polyps (Paris classification[31])
Pedunculated (0-Ip)	31 (14.4)
Non-pedunculated (0-Is; 0-IIa/b/c)	185 (85.6)
Resection in piecemeal technique	170 (78.7)
Final histology
Low-risk invasive adeno-carcinoma	4 (1.9)
Tubular-villous adenoma	102 (47.2)
Tubular adenoma	65 (30.1)
Serrated adenoma	45 (20.8)

Table 2 Histology by localization of the lesions n (%)

Histology	Right-sided colon (n = 149)	Left-sided colon (n = 67)
Low-risk invasive adeno-carcinoma	1 (0.7)	3 (4.5)
Tubular-villous adenoma	63 (42.3)	39 (58.2)
Tubular adenoma	42 (28.2)	23 (34.3)
Serrated adenoma	43 (28.9)	2 (3.0)

Table 3 Risk factors for recurrence (univariate analysis)¹

Variable	Recurrence (fraction/%)	OR (95%CI)	P value2
Age
< 65 yr	10/96 (11.4%)	2.492	0.011
> 65 yr	23/120 (19.2%)	(1.182-5.252)
Size
< 30 mm	19/153 (12.4%)	2.472	0.005
> 30 mm	14/63 (22.2%)	(1.233-4.957)
Morphology
Paris 0-Ip (pedunculated)	0/31 (0%)	26.386	0.018
Paris 0-Is, 0-II a, b, c (sessile/flat)	33/185 (17.8%)	(0.473-1472.565)
Localization
Right-sided colon	31/149 (20.8%)	7.475	0.002
Left-sided colon or rectum	2/67 (3.0%)	(1.787-31.264)
Resection technique
Piecemeal (fragmented)	30/170 (17.6%)	3.741	0.01
En bloc	3/46 (6.5%)	(1.139-12.292)
Histology
Tubular-villous adenoma	25/103 (24.3%)	3.417	0.002
Tubular, serrated, carcinoma	8/113 (7.1%)	(1.533-7.614)

¹The overall recurrence rate was 33/216 (15.3%);

²As calculated with the Kaplan-Meier method.

Table 4 Risk factors for recurrence (multivariate analysis)¹

Variabel	HR (95%CI)	P value
Size > 30 mm	2.563 (1.179-5.570)	0.017
Localization right-sided colon	6.842 (1.540-30.394)	0.011
Histology tubular-villous adenoma	3.713 (1.617-8.528)	0.002

¹The factors age, morphology, resection technique were not significant in multivariate analysis.

Table 5 Reported associations with adenoma recurrence from the literature

Ref.	Lesions (n)	Size	Localization	Piecemeal resection
Luigiano et al[14]	148	> 40 mm
Lim et al[28]	239		Left-sided
Mannath et al[29]	121			Yes
Sakamoto et al[18]	222			Yes (> 5 pieces)
Woodward et al[19]	423			Yes
Cipolletta et al[30]	1012	> 30 mm	Right-sided	Yes
Moss et al[22]	799	> 40 mm
Oka et al[23]	1029	> 40 mm		Yes
Briedigkeit et al (this study)	216	> 30 mm	Right-sided	Yes (univariate only)