Impact of preoperative chemoradiotherapy using concurrent S-1 and CPT-11 on long-term clinical outcomes in locally advanced rectal cancer

Table 5 Pathological tumor characteristics, n (%)

Pathological tumor characteristics	n = 82
ypT stage
0	13 (15.9)
1	5 (6.1)
2	21 (25.6)
3	25 (42.7)
4	8 (9.8)
ypN stage
−	65 (79.3)
+	17 (20.7)
yp TNM stage1
0	13 (15.9)
I	20 (24.4)
II	32 (39.0)
III	17 (20.7)
Residual tumor classification
R0	79 (96.3)
R1	3 (3.7)
R2	0
Histology
well/moderately differentiated	66 (80.5)
Poorly differentiated/mucinous/signet	16 (19.5)
T downstaging
−	41 (50.0)
+	41 (50.0)
N downstaging
−	46 (56.1)
+	36 (43.9)
Tumor regression grade
1a	18 (22.0)
1b	12 (14.6)
2	39 (47.6)
3	13 (15.9)
Adjuvant chemotherapy
–	56 (68.3)
+	26 (31.7)

¹According to the National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology. R0: No residual tumor confirmed microscopically; R1: Microscopic tumor residue; R2: Macroscopic tumor residue.