A total of 311 patients with right-sided colon cancer adenocarcinoma underwent laparoscopic right hemicolectomy in two medical centers. The 3-LRHC received 148 patients, and 5-LRHC received 156 patients. Seven patients who underwent 3-LRHC were converted to additional 4-LRHC due to intra-abdominal adhesions and severe bowel dilatation. They were included in 3-LRHC groups of analysis. Table 1 shows the clinical characteristics before the matching analysis.
Table 1. Clinical characteristics in unmatched patients
Variable
|
3-LRHC (n=156)
|
5-LRHC (n=155)
|
P-value
|
Age (year)
|
67.85 ± 11.09
|
69.79 ± 11.36
|
0.244
|
Male/Female
|
74(47.4%) / 82(52.6%)
|
79(51.0%)/76(49.0%)
|
0.571
|
BMI (kg/m2)
|
23.6 ± 2.9
|
23.3 ± 3.2
|
0.45
|
ASA
|
|
|
0.012
|
1
|
0(0.00%)
|
0(0.00%)
|
|
2
|
100(64.1%)
|
121(78.1%)
|
|
3
|
54(34.6%)
|
32(42.9%)
|
|
4
|
2(1.3%)
|
2(1.3%)
|
|
Underlying disease
|
|
|
|
HTN
|
65(41.7%)
|
79(51.0%)
|
0.112
|
DM
|
35(22.4%)
|
44(28.4%)
|
0.243
|
Coronary disease
|
17(10.9%)
|
10(6.5%)
|
0.226
|
Pulmonary disease
|
18(12.2%)
|
5(3.2%)
|
0.008
|
History of abdominal surgery
|
29(18.6%)
|
21(13.5%)
|
0.280
|
Location of tumor
|
|
|
0.241
|
Cecum
|
29(18.6%)
|
22(14.2%)
|
|
Ascending colon
|
87(55.8%)
|
91(58.7%)
|
|
Hepatic flexure colon
|
24(15.4%)
|
17(11.0%)
|
|
Transverse colon
|
16(10.3%)
|
25(16.1%)
|
|
Obstruction
|
73(46.8%)
|
51(32.9%)
|
0.015
|
Emergency
|
73(46.8%)
|
51(32.9%)
|
0.015
|
Values are presented as number (%) or mean ± standard deviation.
3-LRHC, three ports laparoscopic right hemicolectomy; 5-LRHC, five ports laparoscopic right hemicolectomy; BMI, Body mass index; ASA, American Society of Anesthesiologists; HTN, Hypertension; DM, Diabetes mellitus.
After the propensity score matching, 108 patients were selected from each group. The clinical characteristics of matched cohorts were similar between the 3-LRHC and 5-LRHC as shown in Table 2. Age, sex, BMI, history of abdominal surgery, location of tumor, and cases of emergency surgery were not significantly different between the 3-LRHC and 5-LRHC groups. Although there was difference in the history of hypertension, the ASA used as a matching variable was not significant in the two groups. Therefore, it is evident that the overall condition of the patients before the surgery was similar in both the groups.
Table 2. Clinical characteristics in PS matched patients
Variable
|
3-LRHC (n=108)
|
5-LRHC (n=108)
|
P-value
|
Age (year)
|
69.7 ± 10.8
|
69.3 ± 11.3
|
0.811
|
Male/Female
|
49(45.4%) / 59(54.6%)
|
49(45.4%)/59(54.6%)
|
1
|
BMI (kg/m2)
|
23.6 ± 2.9
|
23.3 ± 3.2
|
0.45
|
ASA
|
|
|
1
|
1
|
0(0.00%)
|
0(0.00%)
|
|
2
|
80 (74.1%)
|
80 (74.1%)
|
|
3
|
26 (24.1%)
|
27 (25.0%)
|
|
4
|
2 (1.9%)
|
1 (0.9%)
|
|
Underlying disease
|
|
|
|
HTN
|
39 (36.1%)
|
62 (57.4%)
|
0.003
|
DM
|
24 (22.2%)
|
32 (29.6%)
|
0.277
|
Coronary disease
|
11 (10.2%)
|
6 (5.6%)
|
0.156
|
Pulmonary disease
|
5(4.6%)
|
3(2.8%)
|
0.721
|
History of abdominal surgery
|
18(16.7%)
|
17(15.7%)
|
0.854
|
Location of tumor
|
|
|
0.287
|
Cecum
|
22 (20.4%)
|
17 (15.7%)
|
|
Ascending colon
|
61 (56.5%)
|
60 (55.6%)
|
|
Hepatic flexure colon
|
15 (13.9%)
|
12 (11.1%)
|
|
Transverse colon
|
10 (9.3%)
|
19 (17.6%)
|
|
Obstruction
|
46 (42.6%)
|
43 (31.5%)
|
0.091
|
Emergency
|
46 (42.6%)
|
34 (31.5%)
|
0.091
|
Values are presented as number (%) or mean ± standard deviation.
3-LRHC, three ports laparoscopic right hemicolectomy; 5-LRHC, five ports laparoscopic right hemicolectomy; BMI, Body mass index; ASA, American Society of Anesthesiologists; HTN, Hypertension; DM, Diabetes mellitus.
For intraoperative outcomes, the mean operative time except in cases of open conversion was shorter in the 3-LRHC group than in the 5-LRHC group (149.0±29.3 for 3-LRHC vs. 186.2 ± 21.2 for 5-LRHC, p<0.001) as shown in Table 3. No significant difference in the case of adhesion in the intra-abdominal cavity (42.5% vs. 43.5%, p=0.210) and rate of conversion to open surgery (12.0% vs. 9.3%, p=0.399) was observed between the two groups.
Table 3. Intraoperative outcomes in PS matched patients
Variable
|
3-LRHC (n=108)
|
5-LRHC (n=108)
|
P-value
|
Operation time (min), mean
|
149.0 ± 29.3
|
186.2 ±21.2
|
<0.001
|
(Exclude open conversion)
|
|
|
|
Adhesion
|
38 (42.5%)
|
47 (43.5%)
|
0.210
|
Open conversion
|
13 (12.0%)
|
10 (9.3%)
|
0.399
|
Cause of conversion
|
|
|
0.089
|
Adhesion
|
12(11.1%)
|
5(4.6%)
|
|
Bleeding
|
0(0.0%)
|
3(2.8%)
|
|
Field of vision
|
1(0.9%)
|
2(1.9%)
|
|
Values are presented as number (%) or mean ± standard deviation.
3-LRHC, three ports laparoscopic right hemicolectomy; 5-LRHC, fiver ports laparoscopic right hemicolectomy
Postoperative outcomes were analyzed except for patients with open surgery in Table 4. As an indicator of recovery of postoperative bowel function, the first passage of flatus was earlier in the 3-LRHC group than in the 5-LRHC group (2.23±1.11days vs 2.50±1.12 days; p=0.095). The first oral diet was earlier in the 3-LRHC group than in the 5-LRHC group (2.96±1.44days vs 3.60±2.15 days; p=0.016). The day of the Jackson-Pratt (JP) drain removal without intra-abdominal complications was also 6.65± 2.15 in the 3-LRHC group, which was significantly shorter than 7.57±1.20 in the 5-LRHC group (p=0.02). However, the days of hospitalization were similar in both groups (6.98±3.00 in the 3-LRHC group vs 8.32± 3.55 in the 5-LRHC group; p=0.05). The pain score were similar in the 3-LRHC and 5-LRHC groups (4.23±0.78 vs 4.26±0.84; p=0.773) on the day of surgery. After PCA was completed, the NRS scores were also not significantly different for the two groups (3.26±1.05 vs 3.33±1.01; p= 0.641).
Table 4-1. Postoperative outcomes in PS matched patients (except of patients with open surgery)
|
3-LRHC (n=95)
|
5-LRHC (n=98)
|
P-value
|
The first passage of flatus (days)
|
2.23 ± 1.13
|
2.50 ± 1.09
|
0.095
|
The first oral diet (days)
|
2.96 ± 1.44
|
3.60 ± 2.15
|
0.016
|
Day of JP drain removal
|
6.65 ± 2.15
|
7.57 ± 1.20
|
0.02
|
Hospital stays (days)
|
6.98 ± 3.00
|
8.32 ± 3.55
|
0.05
|
NRS score on POD 1day
|
4.23 ± 0.78
|
4.26 ± 0.84
|
0.773
|
NRS score after PCA
|
3.26 ± 1.05
|
3.33 ± 1.01
|
0.641
|
Postoperative complication
|
|
|
0.103
|
Wound
|
2 (2.1%)
|
5 (5.1%)
|
|
Ileus
|
3 (3.2%)
|
7 (5.1%)
|
|
Lung
|
0 (0.0%)
|
0 (0.0%)
|
|
AKI
|
1 (1.1%)
|
0 (0.0%)
|
|
Bleeding
|
1 (1.1%)
|
0 (0.0%)
|
|
Intraoperative fluid collection
|
0 (0.0%)
|
1 (0.0%)
|
|
Clavien-Dindo classification
|
|
|
0.017
|
Grade 1
|
3 (3.2%)
|
10 (10.2%)
|
|
Grade 2
|
2 (2.1%)
|
2 (2.0%)
|
|
Above grade 3
|
2 (2.1%)
|
1 (1.02%)
|
|
Values are presented as number (%) or mean ± standard deviation.
3-LRHC, three ports laparoscopic right hemicolectomy; 5-LRHC, fiver ports laparoscopic right hemicolectomy; JP, Jackson-Pratt drain; NRS, numeral rating scale; POD, postoperative day; PCA, patient-controlled analgesia; AKI, acute kidney injury.
Clavien-Dindo classification, grade 1: any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiological interventions. Acceptable therapeutic regimens are drug as antiemetics, antipyretics, analgesics, diuretics and electrolytes and physiotherapy.; grade 2: requiring pharmacological treatment with drugs other than such allowed for grade 1 complications.; grade 3: requiring surgical, endoscopic or radiological intervention.; grade 4: life-threatening complication requiring intensive care/ intensive care unit management.; grade 5: death of a patient.
Postoperative complications were not significantly different, but wound problem and paralytic ileus occurred more frequently in the 5-LRHC group. However, as measured by the Clavien-Dindo classification, most of them were grade 1 or 2, which resolved with conservative treatment. (* grade 1: any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiological interventions. Acceptable therapeutic regimens are drugs, such as antiemetics, antipyretics, analgesics, diuretics and electrolytes and physiotherapy; grade 2: requiring pharmacological treatment with drugs other than those allowed for grade 1 complications.)
In table 5 for pathological characteristics, the stage of cancer was selected as a matching variable without any difference between the two groups. Thus, there was no significant difference in the T and N stages. The maximal diameter of tumor between the two groups were not different (5.16±2.80 in the 3-LRHC vs 5.19±3.05 in the 5-LRHC; p=0.932), but the proximal free margin (24.18±14.08 in the 3-LRHC vs 15.48±8.45 in the 5-LRHC; p=0.001) and distal free margin (18.60±8.55 in the 3-LRHC vs 12.90±5.30 in the5-LRHC; p=0.001) was longer in the 3-LRHC than in 5-LRHC. The number of harvested lymph nodes were not significantly different in the two groups (28.66±12.41 vs 26.13±11.32; p=0.119).
Table 5. Pathological characteristics in PS matched patients
|
3-LRHC (n=108)
|
5-LRHC (n=108)
|
P-value
|
Tumor extent
|
|
|
0.417
|
T1
|
19 (17.6%)
|
18 (16.7%)
|
|
T2
|
8 (7.4%)
|
6 (5.6%)
|
|
T3
|
66 (61.1%)
|
75 (69.4%)
|
|
T4a
|
12(11.1%)
|
6(8.3%)
|
|
T4b
|
3(2.8%)
|
0(0.0%)
|
|
Lymph node metastasis
|
|
|
0.833
|
N0
|
60 (55.6%)
|
66(61.1%)
|
|
N1
|
29(26.9%)
|
28(25.9%)
|
|
N2
|
19(17.6%)
|
14(13.0%)
|
|
Stage
|
|
|
0.936
|
Localized cancer
|
59(47.6%)
|
65(52.4%)
|
|
Regional cancer
|
38(52.8%)
|
34(47.2%)
|
|
Distant cancer
|
44(55.5%)
|
9(45.0%)
|
|
Tumor size (cm)
|
5.16 ± 2.80
|
5.19 ± 3.05
|
0.932
|
Proximal free margin (cm)
|
24.18 ± 14.08
|
15.48 ± 8.45
|
0.001
|
Distal free margin (cm)
|
18.60 ± 8.55
|
12.90 ± 5.30
|
0.001
|
Harvested lymph nodes (n)
|
28.66 ± 12.41
|
26.13 ± 11.32
|
0.119
|
Values are presented as number (%) or mean ± standard deviation.
3-LRHC, three ports laparoscopic right hemicolectomy; 5-LRHC, fiver ports laparoscopic right hemicolectomy.
Figure 2 shows the overall survival rate and disease-free survival rates for the two groups except for patients who underwent open surgery. Patients in the two groups were classified into localized, regional stage and analyzed, according to the American cancer society (ACS) in 2016.