Table 1. Clinicopathological characteristics of the study patients.

Variable	Total regression	Residual disease	P
Age, median (IQR)	59 (51–69)	54 (49–64)	0.129
Gender			0.859
Male	17 (68%)	35 (70%)
Female	8 (32%)	15 (30%)
Distance from anal verge, cm, median (IQR)	4 (3–6)	4(3–5)	0.719
Pre-PCRT CEA, ng/dL, median (IQR)  Within normal range, ≤ 6 ng/mL  Increased	2.2 (1.8–3.5) 21 (84%) 4 (16%)	3.5(1.6–7.3) 36 (72%) 14 (28%)	0.275 0.251
Clinical T stage before PCRT  cT2  cT3  cT4	2 (8%) 20 (80%) 3 (12%)	3 (6%) 38 (76%) 9 (18%)	0.775
ypT stage  ypT0  ypT1  ypT2  ypT3  ypT4	25 (100%) - - - -	0 8 (16%) 16 (32%) 23 (46%) 3 (6%)
ypN stage  ypN0  ypN1  ypN2	25 (100%) - -	37 (74%) 11 (22%) 2 (4%)	0.02

IQR, interquartile range; PCRT, preoperative chemoradiotherapy; CEA, carcinoembryonic antigen