Tumor regression grades: Potential outcome predictor of locally advanced rectal adenocarcinoma after preoperative radiotherapy

Table 1 Clinical parameters

Variables	n (%)
Sex
Male	118 (62.1)
Female	72 (37.9)
Age (yr)
< 65	129 (67.9)
≥ 65	61 (32.1)
Tumor height (cm)
< 6	113 (59.5)
≥ 6	77 (40.5)
Pre-TNM
II	30 (15.8)
III	160 (84.2)
Pre-RT	190
Surgical procedure
LAR	127 (66.8)
APR	58 (30.6)
Other	5 (2.6)
Perioperative complications
Morbidity	43 (22.6)
Abdominal or pelvic abscess	8
Anastomosis leak	11
Reoperation	11

TNM: Tumor node metastasis; Pre-RT: Preoperative radiotherapy.

Table 2 Pathological parameters and clinical long-term outcome n (%)

Variables
Postoperative stage
0	5 (2.6)
I	49 (25.8)
II	52 (27.4)
III	84 (44.2)
Mandard TRG
Good response (1 or 2)	24 (12.6)
Bad response (3-5)	166 (87.4)
Overall recurrence of disease
Local	17 (8.9)
Distant	66 (39.8)
Local and distant	7 (3.7)
5-yr OS	65.3% ± 2.2%
5-yr DFS	61.4% ± 4.4%

OS: Overall survival; DFS: Disease-free survival; TRG: Tumor regression grades.

Table 3 Comparison between tumor regression grades and demographic and clinic variables n (%)

Parameter	TRG1 + 2	TRG3 + 4 + 5	P value
Sex
Male	17 (70.8)	101 (60.8)	0.379
Female	7 (29.2)	65 (39.2)	Fisher's Test
Age (yr)
< 65	15 (62.5)	114 (68.7)	0.284
≥ 65	9 (37.5)	52 (32.3)	Fisher's Test
Tumor height (cm)
< 6	10 (41.7)	104 (62.7)	0.0501
≥ 6	14 (58.3)	62 (27.3)	χ2 =3.847
Clinical stage
II	5 (20.8)	25 (15.1)	0.547
III	19 (79.2)	141 (84.9)	Fisher's Test
Surgical procedure
LAR	20 (83.3)	107 (64.5)	0.173
APR + other	4 (16.7)	59 (35.5)	Fisher's Test
Pathological N-stage
ypN0	18 (75.0)	85 (51.2)	0.0311
ypN1	6 (25.0)	81 (48.8)	Fisher's Test
Pathological T-stage
ypT0-2	18 (75.0)	47 (28.3)	0.0001
ypT3-4	6 (25.0)	119 (71.7)	Fisher's Test

¹Fisher's exact test 2-sided. TRG: Tumor regression grades.

Table 4 Tumor regression grade and clinical long-term outcome

Variables		P value
5-yr OS
Mandard good response (TRG1/2)	96.4% ± 2.0%	0.0021
Mandard good response (TRG3-5)	83.1% ± 4.2%
ypCR (Mandard TRG1)	100.00%2	0.6911
Mandard partial response (TRG2)	86.68%2
5-yr DFS
Mandard good response (TRG1/2)	92.0% ± 3.5%	0.0001
Mandard good response (TRG3-5)	72.3% ± 3.8%
ypCR (Mandard TRG1)	100.00%2	0.5021
Mandard partial response (TRG2)	86.68%2

¹Log rank test;

²No statistics were computed because all cases were censored. Univariate analysis follow-up: mean 56 mo (range: 3-125 mo). OS: Overall survival; DFS: Disease-free survival; TRG: Tumor regression grades.