Ratio of metastatic lymph nodes is more important for rectal cancer patients treated with preoperative chemoradiotherapy

Table 1 Patient and tumor characteristics n (%)

	Non-PCRT,n = 724	PCRT,n = 243	P value
Age (mean ± SD) (yr)	54 ± 10.3	59.2 ± 11.3	< 0.001
< 50	154 (21.3)	80 (32.9)
50-65	346 (47.8)	130 (53.5)	< 0.001
> 65	224 (30.9)	33 (13.6)
Gender			0.005
Male	434 (59.9)	148 (60.9)
Female	290 (40.1)	95 (39.1)
Location1			< 0.001
6-10 cm	474 (65.5)	100 (41.2)
≤ 5 cm	250 (34.5)	143 (58.8)
Sphincter preservation	600 (82.9)	177 (72.8)	< 0.001
Among patients with low rectum	133 (53.2)	81 (56.6)	0.370
LNR2	0.25 ± 0.24	0.252 ± 0.19	0.170
Number of harvested LNs	18.2 ± 8.5	14.8 ± 7.1	< 0.001
< 12 LNs harvested	153 (21.1)	96 (39.5)	< 0.001
Number of positive LNs	3.9 ± 3.7	2.8 ± 2.8	< 0.001
p/yp N category			< 0.001
p/yp N1	445 (61.5)	181 (74.5)
p/yp N2	279 (38.5)	62 (25.5)
Follow-up duration, (Interquartile range) (mo)	60 (39-80)	56 (43-68)	0.540

¹From the anal verge;

²Lymph node ratio. PCRT: Preoperative chemoradiotherapy; LNR: Lymph node ratio; LNs: Lymph nodes.