Perineural invasion as a prognostic factor in patients with stage I-III rectal cancer – 5-year follow up

Table 1 General characteristics of rectal cancer patients

Variable	RC
Age (mean ± SD)	62.27 ± 10.74
Gender (male/female), n (%)	150 (61)/90 (29)
BMI (mean ± SD)	25.27 ± 3.55
T stage, n (%)
1	42 (17)
2	56 (23)
3	117 (48)
4	30 (12)
N stage, n (%)
0	146 (60)
1	61 (25)
2	38 (15)
TNM stage AJCC, n (%)
I	87 (36)
II	59 (24)
III	99 (40)
Patological differentiation, n (%)
Well	188 (76)
Moderate	50 (21)
Poor	7 (3)
Lymphovascular invasion, n (%)
Absent	153 (62)
Present	92 (38)
Perineural invasion, n (%)
Absent	199 (81)
Present	46 (19)
Residual status, n (%)
R0	212 (87)
R1	33 (13)
Adjuvant therapy, n (%)
Yes	104 (42)
No	141 (58)
Smoking, n (%)
Ever	173 (70)
Never	72 (30)
Average size of tumor (mm)	152 ± 292

RC: Rectal cancer; BMI: Body mass index.

Table 2 Clinicopathological characteristics in patients with and without perineural invasion and lymphovascular invasion

Characteristics	PNI absent	PNI present	P value	LVI absent	LVI present	P value
Age	62.39 ± 10.58	61.72 ± 11.58	0.730	61.89 ± 10.52	62.89 ± 11.14	0.491
Gender (male/female)	123/76	27/19	0.409	97/56	53/39	0.222
BMI	25.46 ± 3.58	24.40 ± 3.33	0.067	25.66 ± 3.66	25.61 ± 3.27	0.270
CEA	11.58 ± 38.33	31.37 ± 148.37	0.379	9.85 ± 39.11	24.44 ± 108.03	0.223
CA 19-9	16.86 ± 23.88	48.24 ± 158.40	0.192	15.64 ± 22.25	34.74 ± 114.60	0.123
T stage, n (%)
T1	42 (100)	0 (0)	0.000	41 (98)	1 (2)	0.000
T2	54 (96)	2 (4)		44 (79)	12 (21)
T3	90 (77)	27 (23)		59 (50)	58 (50)
T4	13 (43)	17 (57)		9 (30)	21 (70)
N stage, n (%)
0	137 (94)	9 (6)	0.000	123 (84)	23 (16)	0.000
1	39 (64)	22 (36)		24 (39)	37 (61)
2	23 (60)	15 (40)		6 (16)	32 (84)
TNM, n (%)
Stage I	86 (99)	1 (1)	0.000	81 (93)	6 (7)	0.000
Stage II	51 (86)	8 (14)		42 (71)	17 (29)
Stage III	62 (63)	37 (37)		30 (30)	69 (70)
Differentiation grade, n (%)
Well	157 (83)	31 (17)	0.023	125 (66)	63 (34)	0.018
Moderate	39 (78)	11 (22)		25 (50)	25 (50)
Poor	3 (43)	4 (57)		3 (43)	4 (57)

PNI: Perineural invasion; LVI: Lymphovascular invasion; BMI: Body mass index.