Response to chemoradiotherapy and lymph node involvement in locally advanced rectal cancer

Table 1 Characteristics of the sample population (n = 130)

		n (%)
Age	Mean	67.4 ± 10.6
	Range	42-86
Gender	Male	87 (66.9)
	Female	43 (33.1)
Tumor location	Mid rectum	75 (57.7)
	Low rectum	55 (42.3)
Tumor differentiation	Well	68 (52.3)
	Moderate	53 (40.8)
	Poor	9 (6.9)
Staging method	Endorectal ultrasound	119 (91.5)
	Magnetic resonance imaging	47 (36.2)
Radiotherapy	45 Gy	84 (64.6)
	50.4 Gy	46 (35.4)
Interval to surgery	Mean	7.1 ± 1.1
	Range	5-12
Surgical procedures	Low anterior resection	55 (42.3)
	Abdominoperineal resection	47 (36.2)
	Hartmann procedure	25 (19.2)
	Total proctocolectomy	3 (2.3)

Table 2 Tumor staging

	n	%
Pelvic MRI (n = 47)
T3N1	21	44.6
T3N0	12	25.5
T3N2	4	8.5
T4N0	3	6.4
T4N1	3	6.4
T2N1	2	4.3
T4N2	2	4.3
ERUS (n = 119)
T3N1	53	44.6
T3N0	50	42
T4N1	9	7.6
T4N0	3	2.5
T2N1	3	2.5
T3N2	1	0.8

MRI: Magnetic resonance imaging; ERUS: Endorectal ultrasound.

Table 3 Postoperative pathologic evaluation (ypTN stage) (n = 130)

ypTN	n	%
T0N0	19	14.6
T1N0	10	7.7
T2N0	21	16.2
T3N0	38	29.2
T4N0	2	1.5
T0N1	3	2.3
T2N1	6	4.6
T3N1	16	12.3
T4N1	3	2.3
T3N2	11	8.5
T4N2	1	0.8

Table 4 Tumor regression grading according to Mandard et al[11] scoring system

TRG	n	%
1	19	14.6
2	18	13.9
3	39	30
4	41	31.5
5	13	10

TRG: Tumor regression grading.