Expanding endoscopic boundaries: Endoscopic resection of large appendiceal orifice polyps with endoscopic mucosal resection and endoscopic submucosal dissection

Table 1 Baseline patient characteristics, n (%)

	Total patients (n = 19)
Age, yr (mean ± SD)	63.3 ± 10.8
BMI, kg/m2(mean ± SD)	28.9 ± 6.4
Sex
Male	9 (47)
Female	10 (53)
Race
Caucasian	18 (95)
African American	1 (5)
Comorbidities
Family history of colon cancer	0 (0)
Smoking history	9 (47)
Alcohol use	12 (63)
COPD	2 (11)
CAD	2 (11)
ESRD	0 (0)
Prior appendectomy	2 (11)

n: Number; SD: Standard deviation; BMI: Body mass index; COPD: Chronic obstructive pulmonary disease; CAD: Coronary artery disease; ESRD: End-stage renal disease.

Table 2 Endoscopic results of appendiceal polyp resection by procedure type, n (%)

	Total	EMR	ESD	Hybrid EMR/ESD	P value
Total patients (n)	19	5	6	8
Polyp Appearance (mean ± SD)
Size (mm)	25.5 ± 14.2	26.0 ± 13.4	25.0 ± 18.4	25.6 ± 13.2	0.99
Localized to appendix (at or inside the appendiceal orifice)	14 (74)	3 (60)	6 (100)	5 (63)
50% or more involvement of the appendiceal orifice	13 (68)	3 (60)	5 (83)	5 (63)
Granular, lateral-spreading	5 (26)	0 (0)	2 (33)	3 (30)
Flat, lateral-spreading	1 (5)	0 (0)	0 (0)	1 (13)
Not lateral-spreading	13 (68)	5 (100)	4 (67)	4 (50)
Paris classification: Is	12 (63)	3 (60)	2 (33)	7 (88)
Lesion fibrosis	2 (11)	0 (0)	0 (0)	2 (25)
Procedure (mean ± SD)
Duration of Procedure (min)	61.6 ± 37.9	43.8 ± 31.5	71.0 ± 54.4	65.8 ± 26.1	0.48
Procedures needing clips	18 (95)	4 (80)	6 (100)	8 (100)
Number of clips used	3.9 ± 1.6	2.8 ± 0.5	3.5 ± 2.2	5.0 ± 1.2	0.02
Additional resection of non-appendiceal polyps	4 (21)	2 (40)	0 (0)	2 (25)
ESD knife used (DualKnife/Orise ProKnife)	N/A	N/A	4/2 (67/33)	7/1 (88/12)
Traction method used	3 (21)	0 (0)	1 (16.7)	2 (25)
Stabilization (Dilumen or Pathfinder)	10 (53)	1 (20)	4 (67)	5 (63)
Hemostasis needed (with Cograsper)	3 (16)	0 (0)	2 (33)	1 (13)
Outcome (mean ± SD)
Admission for post-procedure observation	2 (11)	0 (0)	1 (17)	1 (13)
Duration of Admission (d)	2.5 ± 2.1	0 ± 0	4.0 ± 0	1.0 ± 0
Post-Procedure Pain	1 (5)	0 (0)	1 (17)	0 (0)
Adenoma on pathology report	19 (100)	5 (100)	6 (100)	8 (100)
Submucosal/Perineural/Lymphovascular Invasion	0 (0)	0 (0)	0 (0)	0 (0)
R0 rate for en bloc resection	14 (88)a	4 (80)	6 (100)	4 (80)a	0.56
Curative resection rate	14 (74)	4 (80)	6 (100)	4 (50)	0.11
En Bloc resection rate	16 (84)	5 (100)	6 (100)	5 (63)	0.09
Repeat colonoscopy done	8 (57)b	0 (0)	2 (67)b	6 (75)

^aThree patients from the hybrid EMR/ESD group were not included as they underwent piecemeal resection.

^bIn the EMR group, one patient died from unrelated causes prior to consideration of a repeat colonoscopy and one patient refused a follow up colonoscopy. In the ESD group, three patients were not due for follow up endoscopy.

EMR: Endoscopic mucosal resection; ESD: Endoscopic submucosal dissection; n: Number; SD: Standard deviation; Is: Protruding and pedunculated; R0: Microscopically margin-negative.