Lymphovascular invasion in rectal cancer following neoadjuvant radiotherapy: A retrospective cohort study

Table 1 Demographic details of patients and tumor characteristics

	PRT n = 103	Control n = 222	P value
Sex
Male	62	130	0.875
Female	41	92
Age (yr)1	56 (52-61)	57 (53-64)	0.232
Distance of tumor from anal verge
< 5 cm	35	53	0.061
5-12 cm	68	169
Surgery
APR	27	55	0.564
LAR	71	161
CR	5	6
Preoperative serum CEA level
Normal	52	121	0.691
Abnormal	35	65
Unknown	16	36
Pretreatment TNM stage (%)
I (T1-2 N0)	0 (0)	43 (19.4)	< 0.01
IIA (T3 N0)	25 (24.3)	63 (28.4)
IIB (T4 N0)	4 (3.9)	5 (2.3)
IIIA (T1-2 N1)	3 (2.9)	8 (3.6)
IIIB (T3-4 N1)	33 (32.0)	43 (19.4)
IIIC (AnyT N2)	38 (36.9)	60 (27.0)
Pathologic TNM stage (%)
I (T1-2 N0)	35 (34.0)	55 (24.8)	0.377
IIA (T3 N0)	27 (26.2)	62 (27.9)
IIB (T4 N0)	1 (1.0)	1 (5.0)
IIIA (T1-2 N1)	6 (5.8)	7 (3.2)
IIIB (T3-4 N1)	18 (17.5)	45 (20.3)
IIIC (AnyT N2)	16 (15.5)	52 (23.4)
Histological differentiation (%)
High	4 (3.9)	29 (13.1)	< 0.01
Moderate	70 (68.0)	156 (70.3)
Poor	24 (23.3)	27 (12.2)
Mucinous and signet	5 (4.9)	10 (4.5)
LVI (%)
Present	22 (21.4)	58 (26.1)	0.353
Absent	81 (78.6)	164 (73.9)
Disease progression (%)
Local Recurrence	6 (5.8)	32 (14.4)	0.025
Distant Metastasis	22 (21.4)	47 (21.2)	0.969
Death	24 (23.3)	66 (29.7)	0.228

¹Values are medians (interquartile ranges). PRT: Preoperative radiotherapy.

Table 2 The relevance of LVI and pathologic factors

		LVI		Positive rate (%)	P value
		Present	Absent
PRT
ypT	T1	1	5	16.7	0.592
	T2	6	31	16.2
	T3	14	44	24.1
	T4	1	1	50.0
ypN	N0	9	54	14.3	0.057
	N1	9	15	37.5
	N2	4	12	25.0
Histological differentiation	High	1	3	25.0	0.998
	Moderate	15	55	21.4
	Poor	5	19	20.8
	Mucinous and signet	1	4	21.0
Downstaging	Yes	7	34	17.1	0.388
	No	15	47	24.2
Control
pT	T1	0	11	0	< 0.01
	T2	8	50	13.8
	T3	49	98	33.3
	T4	1	5	16.7
pN	N0	15	103	12.7	< 0.01
	N1	15	37	28.8
	N2	28	24	53.8
Histological differentiation	High	7	22	24.1	0.015
	Moderate	34	122	21.8
	Poor	11	16	40.7
	Mucinous and signet	6	4	60.0

Table 3 The association of LVI and prognosis

		PRT		P	Control		P
		Present	Absent		Present	Absent
Disease progression (%)	Yes	10 (38.5)	16 (61.5)	0.014	32 (43.2)	42 (56.8)	< 0.01
	No	12 (15.6)	65 (84.4)		26 (17.6)	122 (82.4)
5-year DFS rate	%	54.5 (12/22)	80.2 (65/81)	0.020	44.8 (26/58)	73.2 (120/164)	< 0.01
5-year OS rate	%	54.5 (12/22)	82.7 (67/81)	< 0.010	48.3 (28/58)	78.0 (128/164)	< 0.01

Table 4 Multivariate analysis of OS by COX model (backward elimination)

Variable	Hazard ratio	95% CI	P value
Distance from anal verge	0.540	0.346-0.845	< 0.01
Serum CEA level	1.334	1.027-1.732	0.031
pTNM stage	1.347	1.198-1.514	< 0.01
LVI	0.450	0.292-0.692	< 0.01