Identifying timing and risk factors for early recurrence of resectable rectal cancer: A single center retrospective study

Table 1 Clinicopathological characteristics of all patients, n (%)

Variable	Total (n = 131)
Age, year	65 (14)
BMI, median (IQR)	24.09 (21.06-26.82)
Gender, male	82 (62.6)
Tumor diameter, cm	4.3 (2.2)
Tumor location
Upper	29 (22.1)
Middle	46 (35.1)
Low	56 (42.7)
Preoperative CEA, median (IQR)	5.1 (2.3-12.5)
Preoperative Hb, median (IQR)	12.5 (11.00-13.7)
Preoperative CCRT	28 (21.4)
Emergency operation	2 (1.5)
Laparoscopic method	89 (67.9)
Cover to open	3 (2.3)
Blood loss, mL, median (IQR)	50 (30-100)
Colostomy	91 (69.5)
Operation time, median (IQR)	228 (165-295)
Postoperative ICU	3 (2.3)
Pathological T
1	3 (2.3)
2	23 (17.6)
3	94 (71.8)
4	11 (8.4)
Pathological N
0	46 (35.1)
1	46 (35.1)
2	39 (29.8)
Pathological stage
1	17 (13)
2	29 (22.1)
3	85 (64.9)
LNR, %, median (IQR)	5.9 (0-21.1)
Histology
Adenocarcinoma	125 (95.4)
Mucinous adenocarcinoma	6 (4.6)
Histological differentiation
Well	2 (1.5)
Moderate	122 (93.1)
Poor	7 (5.3)
Vascular invasion	20 (15.3)
Lymphatic invasion	115 (87.8)
Perineural invasion	63 (48.1)
RAS gene mutation	71 (54.2)
Complications	46 (35.1)
Clavien–Dindo
0	85 (64.9)
1	9 (6.9)
2	19 (14.5)
3	18 (13.7)
Intraabdominal abscess	6 (4.6)
Ileus	18 (13.7)
SSI	12 (9.2)
Anastomosis leakage	16 (12.2)
Reoperation	18 (13.7)
Readmission	13 (9.9)
LOS, d, median (IQR)	9 (7-12)
Median of survival (mo, IQR)
Recurrence-free survival	10.8 (5.3-22.5)
Post-recurrence survival	2.0 (0.9-4.1)
Overall survival	41.2 (22.1-69.1)
Death	94 (71.8)
Local recurrence	30 (22.9)
Distant recurrence	71 (54.2)
Multiple recurrence	30 (22.9)
Liver	43 (32.8)
Lung	40 (30.5)
Lymph node	22 (16.8)
Peritoneum	9 (6.9)

BMI: Body mass index; CEA: Carcinoembryonic antigen; Hb: Hemoglobin; CCRT: Concurrent chemoradiotherapy; ICU: Intensive care unit; LNR: Lymph node ratio; RAS: Rat sarcoma; SSI: Surgical site infections.

Table 2 Recurrence clinicopathological features

Variable	Early (n = 55)	Late (n = 76)	P value
Age, year
< 70	22 (40)	43 (56.6)	0.061
≥ 70	33 (60)	33 (43.4)
Gender
Male	35 (63.6)	47 (61.8)	0.834
Female	20 (36.4)	29 (38.2)
BMI
Normal	31 (56.4)	41 (53.9)	0.99
Obese	5 (9.1)	7 (9.2)
Overweight	16 (29.1)	24 (31.6)
Underweight	3 (5.5)	4 (5.3)
Tumor location
Upper	10 (18.2)	19 (25)	0.568
Middle	19 (34.5)	27 (35.5)
Low	26 (47.3)	30 (39.5)
Tumor dimension, cm
> 5	18 (32.7)	27 (35.5)	0.739
< 5	37 (67.3)	49 (64.5)
CEA, ng/mL
< 5	30 (54.5)	34 (44.7)	0.268
≥ 5	25 (45.5)	42 (55.3)
Hb, g/dL
< 12	25 (45.5)	26 (34.2)	0.193
≥ 12	30 (54.5)	50 (65.8)
Preoperative CCRT
Yes	34 (61.8)	59 (90.8)	0
No	21 (38.2)	7 (9.2)
Emergency operation
Yes	0	2 (2.6)	0.225
No	55 (100)	74 (97.4)
Operation method
Laparoscopy	39 (70.9)	50 (65.8)	0.535
Open	16 (29.1)	26 (34.2)
Blood loss, mL
> 50	23 (41.8)	30 (39.5)	0.787
≥ 50	32 (58.2)	46 (60.5)
Operation time, min
> 225	26 (47.3)	40 (52.6)	0.545
≤ 225	29 (52.7)	36 (47.4)
LNR (%)
> 5.9	27 (49.1)	38 (50)	0.918
≤ 5.9	28 (50.9)	38 (50)
Histology
Adenocarcinoma	53 (96.4)	72 (94.7)	0.66
Non-adenocarcinoma	2 (3.6)	4 (5.3)
Histological differentiation
Well	2 (3.6)	0 (0)	0.012
Moderate	47 (85.5)	75 (98.7)
Poor	6 (10.9)	1 (1.3)
Vascular invasion
Yes	8 (14.5)	12 (15.8)	0.834
No	47 (85.5)	64 (84.2)
Lymphatic invasion
Yes	45 (81.8)	70 (92.1)	0.076
No	10 (18.2)	6 (7.9)
Perineural invasion
Yes	27 (49.1)	36 (47.4)	0.846
No	28 (50.9)	40 (52.6)
RAS gene mutation
Yes	30 (54.5)	41 (53.9)	0.946
No	25 (45.5)	35 (46.1)
Pathological T stage
1	2 (3.6)	1 (1.3)	0.727
2	8 (14.5)	15 (19.7)
3	40 (72.7)	54 (71.1)
4	5 (9.1)	6 (7.9)
Pathological N stage
0	19 (34.5)	27 (35.5)	0.968
1	20 (36.4)	26 (34.2)
2	16 (29.1)	23 (30.3)
Pathological stage
1	9 (16.4)	8 (10.5)	0.469
2	10 (18.2)	19 (25)
3	36 (65.5)	49 (64.5)
LOS, day
> 9	20 (36.4)	36 (47.4)	0.209
≤ 9	35 (63.6)	40 (52.6)
Complication
Yes	18 (32.7)	28 (36.8)	0.626
No	37 (67.3)	48 (63.2)
Clavien–Dindo classification
0	37 (67.3)	48 (63.2)	0.802
1	4 (7.3)	5 (6.6)
2	6 (10.9)	13 (17.1)
3	8 (14.5)	10 (13.2)
Intraabdominal abscess
Yes	3 (5.5)	3 (3.9)	0.684
No	52 (94.5)	73 (96.1)
Ileus
Yes	5 (9.1)	13 (17.1)	0.189
No	50 (90.9)	63 (82.9)
SSI
Yes	6 (10.9)	6 (7.9)	0.555
No	49 (89.1)	70 (92.1)
Anastomosis leakage
Yes	5 (9.1)	11 (14.5)	0.353
No	50 (90.9)	65 (85.5)
Re-operation
Yes	8 (14.5)	10 (13.2)	0.82
No	47 (85.5)	66 (86.8)
Re-admission
Yes	2 (3.6)	11 (14.5)	0.041
No	53 (96.4)	65 (85.5)

BMI: Body mass index; CEA: Carcinoembryonic antigen; Hb: Hemoglobin; CCRT: Concurrent chemoradiotherapy; LNR: Lymph node ratio; RAS: Rat sarcoma; SSI: Surgical site infections.