Table 1.

Patient and Tumor Characteristics and Treatment Factors (N = 725)

Characteristic	Complete Response (T0N0)		Intermediate Response (T1-2N0)		Poor Response (T3-4or N+)		P
	No.	%	No.	%	No.	%
Total No. of patients	131	18.1	211	29.0	384	53.0
Patient and tumor characteristics
Age, years*							.15
Median	57		58.5		56
Range	48–66		49–67		48–65
Sex							.64
Male	80	61.1	137	65.2	237	61.7
Female	51	38.9	73	34.8	147	38.3
Location of tumor, cm from AV							.11†
> 10	13	10.1	4	2.0	25	6.8
6-10	54	42.2	84	41.0	162	43.9
≤ 5	61	47.7	117	57.0	182	49.3
Clinical stage							.08
II	51	38.9	95	45.2	144	37.5
III	74	56.5	98	46.7	195	50.8
Tumor grade							.08
G1, G2	112	91.1	184	91.1	321	85.6
G3, G4	11	8.9	18	8.9	54	14.4
No. of examined lymph nodes*							.22‡
Median	11		11		12
Range	6–17		6–15		7–18
Lymphovascular invasion	0		10	4.8	94	24.5	< .001§
Perineural invasion	0		1	0.5	55	14.3	< .001§
Treatment factors
Radiation dose, Gy*							.10
Median	50.4		50.4		50.4
Range	45–52.13		45–52.5		45–52.5
Concurrent chemotherapy							.10
Fluorouracil	52	39.9	101	48.6	153	39.5
Capecitabine	47	36.2	65	31.3	153	39.5
Other¶	14	10.8	11	5.3	16	4.1
Interval between completion of chemoradiotherapy and surgery, days*							.14
Median	49		50		52
Range	46–57		44–57		45–62
Adjuvant chemotherapy	109	83.2	172	81.9	330	86.2	.36
Fluoropyrimidine only∥	85	78.0	142	82.6	220	66.7	< .001#
Oxaliplatin–based∥	19	17.4	23	13.4	97	29.4
Others∥	2	1.8	2	1.2	10	3.0
Follow–up duration, months*							< .001
Median	75		75		59
Range	39–105		43–116		36–96

Abbreviation: AV, anal verge.

^*Median value with interquartile range.

^†Tumor location was analyzed based on distance (cm) from AV.

^‡Compared with complete response group.

^§Comparison between intermediate and poor response groups.

^¶Targeted agents, oxaliplatin.

^∥Percentage among patients who received adjuvant chemotherapy.

^#Comparison of fluoropyrimidine only v oxaliplatin-based treatment.