Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

Table 6 Perioperative outcomes of 162 cases of laparoscopic radical sphincter-preserving surgery for rectal cancer grouped into two groups of high and low surgical difficulty, the postoperative pathological baseline characteristics and univariate analysis, n (%)

	Univariate analysis
	Whole group (n = 162)	Low surgical difficulty group (n = 141)	High surgical difficulty group (n = 21)	P value
pT staging				0.73901
Tis	4 (2.47)	4 (2.84)	0
T1	19 (11.73)	17 (12.06)	2 (9.52)
T2	26 (16.05)	20 (14.18)	6 (28.57)
T3	109 (67.28)	97 (68.79)	12 (57.14)
T4a	4 (2.47)	3 (2.13)	1 (4.76)
pN staging				0.43271
N0	94 (58.02)	83 (58.87)	11 (52.38)
N1	36 (22.22)	32 (22.7)	4 (19.05)
N2	32 (19.75)	26 (18.44)	6 (28.57)
pTNM staging				0.58951
0	4 (2.47)	4 (2.84)	0
Ⅰ	38 (23.46)	33 (23.4)	5 (23.81)
Ⅱ	52 (32.1)	46 (32.62)	6 (28.57)
III	68 (41.98)	58 (41.13)	10 (47.62)
Degree of tumor differentiation				0.07301
Well differentiated	9 (5.56)	9 (6.38)	0
High-moderate differentiation	20 (12.35)	17 (12.06)	3 (14.29)
Moderate differentiation	112 (69.14)	100 (70.92)	12 (57.14)
Moderate-Low differentiation	17 (10.49)	13 (9.22)	4 (19.05)
Low differentiation	4 (2.47)	2 (1.42)	2 (9.52)
Tumor nodules	16 (9.88)	16 (11.35)	0	0.22952
Vascular tumor emboli	47 (29.01)	40 (28.37)	7 (33.33)	0.83372
Neural invasion	40 (24.69)	36 (25.53)	4 (19.05)	0.71012
Number of Lymph Nodes Removed	15 (13, 18)	15 (13, 18)	15 (12, 17)	0.79291
Surgical duration (min)	216.5 (179.25, 260)	205 (176, 238)	324.19 ± 59.62	3.423e-101
Intraoperative Blood Loss (ml)	50 (20, 100)	50 (20, 50)	100 (50, 200)	4.436e-061
Postoperative complications (CD grade)				0.01851
No complications	125 (77.16)	113 (80.14)	12 (57.14)
Grade I	7 (4.32)	5 (3.55)	2 (9.52)
Grade II	21 (12.96)	17 (12.06)	4 (19.05)
Grade III	8 (4.94)	5 (3.55)	3 (14.29)
Grade IV	1 (0.62)	1 (0.71)	0
Postoperative anastomotic fistula grading				0.09071
No anastomotic fistula	152 (93.83)	134 (95.04)	18 (85.71)
Grade B	6 (3.7)	5 (3.55)	1 (4.76)
Grade C	4 (2.47)	2 (1.42)	2 (9.52)
Duration of postoperative hospital stay (d)	14 (12, 16)	13 (12, 15)	23 (22, 27)	6.01e-111
Intraoperative use of trans-anal approach	7 (4.32)	2 (1.42)	5 (23.81)	0.00041
Conversion to open surgery	1 (0.62)	0	1 (4.76)	0.12962
Postoperative anal evacuation time(d)	2 (2, 3)	2 (2, 3)	2 (2, 2)	0.02841
Postoperative resumption of semi-liquid food time (d)	8 (5, 9)	8 (6, 9)	6 (4, 10)	0.17981

¹The non-parametric Mann Whitney U rank sum test was used for unidirectional ordered information on counts.

²The χ² test, continuity-corrected χ² test or Fisher’s exact probability method was used for bidirectional unordered information. Obedience to normal distribution.

If the normal distribution is satisfied, it is expressed as mean ± SD; if not, it is expressed as median (Q1, Q3). Count and rank information is expressed as examples (%). P values denoted by “e” are all less than 0.001.