TABLE 1. Exclusion Criteria
Patient age < 19 years or > 86 years Pregnancy
History of any malignancy within the past 5 years American Society of Anesthesiologists class ≥ 3 Emergency surgery
Distant metastasis
Rectal, transverse colon, or descending colon cancer Obstructive or perforated colon cancer
Colon cancer associated with familial adenomatous polyposis or hereditary non-polyposis colorectal cancer
Synchronous colorectal cancer
Clinical T4b colon cancer; direct invasion into 1 or more adjacent organs
TABLE 2. Definitions of Measured Outcomes and Complications
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Conversion to reduced- port surgery
Insertion of only 1 additional trocar during SPLS
Conversion to MPLS Insertion of 2 or more additional trocars during SPLS Conversion to open
surgery
Need to extend the skin incision beyondthe designated incision length to extract the resected specimen or to control intraoperative complications
Bleeding Intraoperative or postoperative bleeding requiring blood product transfusion
Another organ injury Any injury of a non-target organ requiring surgical intervention Anastomotic failure Intraoperative finding of gross defect of the anastomotic site or a
positive leak test
Wound infection Surgical wound with purulent discharge
Prolonged ileus Failure of gas passage with small bowel distention by POD 3, which delayed oral intake
Intestinal obstruction Failure of bowel contents because of postoperative adhesions Anastomotic leakage Peritonitis with drainage of feces or pus from the draining tube or
abscess formation around the anastomosis identified radiologically or surgically
MPLS, multiport laparoscopic surgery; POD, postoperative day; SPLS, single-port laparoscopic surgery
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TABLE 3. Subgroup Analysis by Tumor Location
Right colon (n=116) Left colon (n=243)
Variable SPLS
(n=62) MPLS
(n=54) P SPLS
(n=117) MPLS
(n=126) P
Operation time, mean (range), min
185.5 (64–496) 180.3 (70–420) 0.740 170.0 (65–395) 157.5 (61–350) 0.214
Blood loss, mean (range), mL
89.5 (0–800) 61.6 (0–500) 0.214 53.9 (0–600) 44.9 (0–500) 0.419
Conversion to another technique
Reduced-port surgery or MPLS
6 (9.7%) 19 (16.2%)
Open surgery 2 (3.2%) 0(0%) 1 (0.9%) 0(%)
Intraoperative 8 (12.9%) 3 (5.6%) 0.178 5 (4.3%) 4 (3.2%) 0.742
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complications Postoperative complications
11 (17.7%) 10 (18.5%) 0.914 8 (6.8%) 15 (11. 9%) 0.178
Postoperativehospital stay, mean (range), d
7.8 (4–22) 7.8 (4–37) 0.975 6.7 (3–13) 7.2 (4–36) 0.140
Harvested lymph nodes, mean (range)
31.6 (12–81) 31.1 (3–58) 0.822 22.3 (4–51) 20.8 (2–48) 0.164
Proximal resection margin, mean (range), cm
18.5 (6.0–65.0) 17.5 (6.2–105.0) 0.674 9.2 (2.0–26.0) 10.1(3.0–27.0) 0.108
Distal resection margin, mean (range), cm
13.3 (4.5–29.0) 14.2 (2.0–33.0) 0.411 6.7 (1.5–18.0) 6.6 (2.0–17.0) 0.826
MPLS, multiport laparoscopic surgery; SPLS, single-port laparoscopic surgery
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