Table 1.

Clinical characteristics of patients in the primary and validation cohorts

Characteristics	Training cohort		p	Validation cohort		p
	Non-pCR (N = 93)	pCR (N = 20)		Non-pCR (N = 53)	pCR (N = 11)
Age (yr)			.569			.847
≤ 60	62 (66.7%)	12 (60.0%)		37 (69.8%)	8 (72.7%)
> 60	31 (33.3%)	8 (40.0%)		16 (30.2%)	3 (27.3%)
Gender			.668			.586
Female	28 (30.1%)	7 (35.0%)		19 (35.8%)	3 (27.3%)
Male	65 (69.9%)	13 (65.0%)		34 (64.2%)	8 (72.7%)
cT stage			.494			.847
III	80 (86.0%)	16 (80.0%)		42 (79.2%)	9 (81.8%)
IV	13 (14.0%)	4 (20.0%)		11 (20.8%)	2 (18.2%)
cN stage			.197			.707
0	27 (29.0%)	3 (15.0%)		7 (13.2%)	1 (9.1%)
1	66 (71.0%)	17 (85.0%)		46 (86.8%)	10 (90.9%)
cTNM stage			.411			.512
II	27 (29.0%)	4 (20.0%)		9 (17.0%)	1 (9.1%)
III	66 (71.0%)	16 (80.0%)		44 (83.0%)	10 (90.9%)
MRF			.082			.177
Negative	73 (78.5%)	12 (60.0%)		32 (60.4%)	9 (81.8%)
Positive	20 (21.5%)	8 (40.0%)		21 (39.6%)	2 (18.2%)
TL (cm)			.625			.266
≤ 3	23 (24.7%)	6 (30.0%)		11 (20.8%)	4 (36.4%)
> 3	70 (75.3%)	14 (70.0%)		42 (79.2%)	7 (63.6%)
DTVA (cm)			.351			.549
≤ 5	36 (38.7%)	10 (50.0%)		19 (35.8%)	5 (45.5%)
> 5	57 (61.3%)	10 (50.0%)		34 (64.2%)	6 (54.5%)
CEA (ng/mL)			.235			.214
≤ 5	64 (68.8%)	11 (55.0%)		33 (62.3%)	9 (81.8%)
> 5	29 (31.2%)	9 (45.0%)		20 (37.7%)	2 (18.2%)
Tumor thickness (mm) Median (Q1, Q3)	14.00 (11.00, 17.00)	15.50 (13.00, 21.25)	.029*	16.00 (12.00, 18.00)	13.00 (12.50, 18.00)	.419
Rad-score Median (Q1, Q3)	− 1.89 (− 2.21, − 1.56)	− 0.71 (− 1.15, − 0.42)	< .001*	− 1.95 (− 2.28, − 1.51)	− 0.54 (− 1.17, − 0.29)	< .001*

pCR: Complete pathological response; MRF: Mesorectal fascia; TL: Tumor length; DTVA: Distance of tumor from the anal verge; CEA: Carcinoembryonic antigen; cT stage: Clinical T stage, cN stage: Clinical N stage