Table 2.

Univariate analysis to identify predictors of tumor and complete regression

Variable	Tumor regression grade		P value
	0-3	4
Sex			0.940
Male	127	50
Female	52	20
Age (yr)			0.926
≤ 56	96	38
> 56	83	32
Low margin from AV (cm)			0.641
≤ 5	133	54
> 5	46	16
Pre-CRT size (cm)			0.001
≤ 4	73	44
> 4	102	23
cT classification			0.054
cT2, 3	146	64
cT4	33	6
cN classification			0.073
cN -	37	22
cN +	142	48
Pre-CRT involved bowel circumference			0.365
Encircling	65	21
One direction	114	49
Pre-CRT movability			< 0.001
Movable	13	20
Tethered/fixed	166	50
Pre-CRT CEA (ng/mL)1			0.021
≤ 5	97	52
> 5	48	11
ycT classification			< 0.001
ycT 1,2	42	38
ycT 3,4	137	32
ycN classification			< 0.001
ycN -	57	44
ycN +	122	26
Post-CRT size (cm)			< 0.001
≤ 3	115	64
> 3	64	6
Post-CRT morphology			0.004
Benign-like shape	154	69
Malignancy-like shape	25	1
Cell type			0.141
High grade	161	67
Low grade	18	3
Gross Change			< 0.001
Yes	129	67
No	50	3
Post-CRT SUV2			< 0.001
≤ 5	63	29
> 5	86	5

Low grade: Poorly differentiated or mucinous; High grade: Well or moderately differentiated;

¹Missing data: n = 41;

²Missing data: n = 66. AV: Anal verge; CRT: Chemoradiation therapy; CEA: Carcinoembryonic antigen; SUV: Standard uptake value.