Self-expanding metal stent placement and pathological alterations among obstructive colorectal cancer cases

Table 1 Clinical and pathological features of patients with colorectal cancer according to decompression methods

Characteristic1	All cases (n = 102)	Decompression methods		P value2
		Transanal tube (n = 76)	SEMS (n = 26)
Sex, n (%)				0.91
Female	54 (53)	40 (53)	14 (54)
Male	48 (47)	36 (47)	12 (46)
Age, mean ± SD (years)	72.6 ± 12.5	71.7 ± 12.9	75.1 ± 11.1	0.24
Tumor location, n (%)				0.24
Cecum to transverse colon	16 (16)	13 (17)	3 (12)
Descending to sigmoid colon	65 (64)	45 (59)	20 (77)
Rectum	21 (21)	18 (24)	3 (12)
Tumor size, mean ± SD (mm)	40.7 ± 16.2	39.0 ± 14.9	45.4 ± 19.3	0.086
Time from decompression to operation, mean ± SD (days)	13.6 ± 12.9	12.0 ± 7.6	18.2 ± 21.7	0.035
Histological type, n (%)				0.35
Well	29 (28)	19 (25)	10 (38)
Moderate	67 (66)	53 (70)	14 (54)
Mucinous, poor, or signet-ring cell	6 (5.9)	4 (5.3)	2 (7.7)
T stage (depth of tumor invasion), n (%)				0.57
T1 (submucosa)	-	-	-
T2 (muscularis propria)	1 (1.0)	-	1 (3.9)
T3 (subserosa)	67 (66)	54 (71)	13 (50)
T4 (serosa or other organs)	34 (33)	22 (29)	12 (46)
N stage (number of positive lymph nodes), n (%)				0.54
N0 (0)	49 (48)	36 (47)	13 (50)
N1 (1-3)	39 (38)	28 (37)	11 (42)
N2 (4-)	14 (14)	12 (16)	2 (7.7)
AJCC disease stage, n (%)				0.40
I	1 (1.0)	-	1 (3.9)
II	42 (41)	31 (41)	11 (42)
III	36 (35)	27 (36)	9 (35)
IV	23 (23)	18 (24)	5 (19)
Mutation status, n (%)				0.51
KRAS mutated	34 (43)	26 (47)	8 (33)
NRAS mutated	3 (3.8)	2 (3.6)	1 (4.2)
BRAF mutated	0 (0)	0 (0)	0 (0)
Absent	42 (53)	27 (49)	15 (63)

¹Percentage indicates the proportion of patients with a specific clinical characteristic among all patients or in strata of decompression methods.

²We used the chi-square test to compare categorical variables and analysis of variance to compare continuous variables. We adjusted the two-sided α level to 0.05.

AJCC: American Joint Committee on Cancer; SEMS: Self-expanding metal stent.