Patient selection and operative strategies for laparoscopic intersphincteric resection without diverting stoma

Table 1 Clinical and surgical characteristics before and after matching

Variables	Before PSM		P value	After PSM		P value
	DS (n = 421)	SF (n = 84)		DS (n = 78)	SF (n = 78)
Gender			0.042			0.521
Male	273 (64.8)	44 (52.4)		34 (43.6)	39 (50.0)
Female	148 (35.2)	40 (47.6)		44 (56.4)	39 (50.0)
Age, median (range) years	60.0 (20.0, 84.0)	64.0 (23.0, 84.0)	0.003	64.0 (31.0, 82.0)	64.0 (33.0, 84.0)	1
< 60	204 (48.4)	25 (29.8)		25 (32.1)	25 (32.1)
≥ 60	217 (51.6)	59 (70.2)		53 (67.9)	53 (67.9)
BMI, median (range) kg/m2	23.7 (14.5, 32.9)	23.8 (17.8, 34.4)	1	23.9 (17.1, 29.3)	23.7 (17.8, 34.4)	1
< 25	270 (64.1)	54 (64.3)		51 (65.4)	52 (66.7)
≥ 25	151 (35.9)	30 (35.7)		27 (34.6)	26 (33.3)
ASA score			0.005			0.744
I-II	408 (96.9)	75 (89.3)		74 (94.9)	72 (92.3)
III	13 (3.1)	9 (10.7)		4 (5.1)	6 (7.7)
Diabetes			1			0.811
Yes	55 (13.1)	11 (13.1)		9 (11.5)	11 (14.1)
No	366 (86.9)	73 (86.9)		69 (88.5)	67 (85.9)
Tumor size, median (range) mm	35.0 (10.0, 120.0)	35.0 (15.0, 80.0)	0.628	35.0 (20.0, 90.0)	35.0 (15.0, 80.0)	0.958
> 35	209 (49.6)	41 (48.8)		32 (41.0)	36 (46.2)
≤ 35	212 (50.4)	43 (51.2)		46 (59.0)	42 (53.8)
Differentiation status			0.216			0.277
Poor	65 (15.4)	8 (9.5)		10 (12.8)	5 (6.4)
Well-moderate	356 (84.6)	76 (90.5)		68 (87.2)	73 (93.6)
Tumor type			0.944			1
Ulcer	281 (66.7)	57 (67.9)		57(73.1)	57(73.1)
Protrusion	140 (33.3)	27 (32.1)		31(26.9)	31(26.9)
pT stage			0.362			0.255
0-2	181 (43.0)	31 (36.9)		36 (46.2)	28 (35.9)
3	240 (57.0)	53 (63.1)		42 (53.8)	50 (64.1)
pN stage			0.782			0.104
N+	150 (35.6)	28 (33.3)		16 (20.5)	26 (33.3)
N0	271 (64.4)	56 (66.7)		62 (79.5)	52 (66.7)
M stage			1			1
M1	8 (1.9)	1 (1.2)		1 (1.3)	1 (1.3)
M0	413 (98.1)	83 (98.8)		77 (98.7)	77 (98.7)
pTNM stage			0.659			0.104
I-II	154 (36.6)	28 (33.3)		16 (20.5)	26 (33.3)
III-IV	267 (63.4)	56 (66.7)		62 (79.5)	52 (66.7)
nCRT			0.009			1
Yes	62 (14.7)	3 (3.6)		4 (5.1)	3 (3.8)
No	359 (85.3)	81 (96.4)		74 (94.9)	75 (96.2)
Tumor height from anal verge, median (range) cm	4.0 (3.5-4.0)	4.5 (4.0-5.0)	< 0.001	4.0 (4.0-4.5)	4.0 (4.0-4.5)	0.412
≤ 4.0	343 (81.5)	41 (48.8)		48 (61.5)	39 (50.0)
> 4.0	68 (18.5)	43 (51.2)		30 (38.5)	39 (50.0)
Anastomotic height from anal verge, median (range) cm	2.00 (0.50, 4.00)	2.50 (1.00, 4.00)	< 0.001	2.00 (1.00, 4.00)	2.50 (1.00, 4.00)	1
≤ 3.0	406 (96.4)	73 (86.9)		72 (92.3)	72 (92.3)
> 3.0	15 (3.6)	11 (13.1)		6 (7.7)	6 (7.7)
LCA retention			< 0.001			1
Yes	205 (48.7)	61 (72.6)		54 (69.2)	55 (70.5)
No	216 (51.3)	23 (27,4)		24 (30.8)	23 (29.5)
Lateral lymph node dissection			0.260			0.247
Yes	51 (12.1)	6 (7.2)		9 (11.5)	4 (5.1)
No	370 (87.9)	78 (92.8)		69 (88.5)	74 (94.9)
Hb (g/L)			0.911			0.802
≥ 120	366 (86.9)	74 (88.1)		70 (89.7)	68 (87.2)
< 120	55 (13.1)	10 (11.9)		8 (10.3)	10 (12.8)
ALB (g/L)			0.328			0.342
≥ 35.0	334 (79.3)	62 (73.8)		63 (80.8)	57 (73.1)
< 35.0	87 (20.7)	22 (26.2)		15 (19.1)	21 (26.9)
CEA (μg/L)			0.122			0.561
> 5.0	134 (31.8)	19 (22.6)		15 (19.2)	19 (24.4)
≤ 5.0	287 (68.2)	65 (77.4)		63 (80.8)	59 (75.6)

Data are presented as n (%). BMI: Body mass index; ASA: American Society of Anesthesiologists; nCRT: Neoadjuvant chemotherapy; LCA: Left colic artery; Hb: Hemoglobin; ALB: Albumin; PSM: Propensity score matching; DS: Diverting stoma; SF: Stoma-free; CEA: Carcinoembryonic antigen.