Laparoscopic colectomy is widely performed for colon cancer (1), but many variations exist for the method of anastomosis after laparoscopic radical resection for cancer (2–4). Left hemicolectomy may sometimes be a complex procedure [mobilization of the splenic flexure, unexpected adhesions or tumor invasion, intraoperative vascular problems (5, 6). Complete laparoscopic colectomy with an intracorporeal reconstruction technique requires advanced surgical skills and may increase operation time, hospitalization costs, and/or the risk of abdominal contamination (7–9).

The recent advent of barbed sutures has made manual suturing more convenient and quicker because of good tissue adhesion and eliminated need for knot tying. At present, the barbed suture is mainly used for gastrointestinal anastomoses (10, 11) and urinary tract surgery (12), but there are very few reports on left colonic anastomosis.

In this study, we describe the details of a novel extracorporeal anastomosis (ECA) with barbed thread—a knotless hand-sewn end-to-end anastomosis (KHEA) technique—with a video and compare the perioperative outcomes of KHEA to those of stapled anastomosis.

In this study, the mean duration for completion of anastomosis and operation costs were statistically significantly decreased in the KHEA group, while no statistically significant difference was found in the rate of postoperative complications, delay to bowel function recovery, or duration of hospital stay.

The minimally invasive approach for colectomy can be performed via either a “minimally invasive assisted” technique with ECA or a “total minimally invasive” technique with intracorporeal anastomosis (ICA), i.e., performing the anastomosis in the abdominal cavity under the direct view of a laparoscope. In recent years, ICA has received increasing focus, but its superiority over extracorporeal anastomosis is still inconclusive (16). Several studies have shown that that ICA has advantages over ECA such as shorter length of incision, less estimated blood loss, and shorter time to bowel function recovery (2, 17, 18). However, two recent high-quality randomized controlled trials (8, 19) and one study on robotic left colectomy (20) failed to show that outcomes after ICA were better than after ECA. The advantages of the KHEA technique could be a further argument in favor of the ICA technique.

For left hemicolectomy, anastomosis can be performed either manually or with staplers. As reported, no statistically significant superiority has been found between these two methods with respect to safety or anastomotic leakage (4, 21). Based on our experience, an end-to-end hand-sewn anastomosis could save approximately 3–5 cm of colon segment compared with stapled anastomosis, enabling surgeons to avoid unnecessary mobilization of the colon and the longitude tension of anastomosis. However, the traditional hand-sewing anastomosis technique requires higher technical skills from surgeons and takes a longer operation time than stapled anastomosis. In our experience, the hand-sewn technique using the new KHEA technique facilitates an easy anastomosis with comparable outcomes.

We extract the bowel specimen from a left lower quadrant incision, approximately 5 cm long. Compared with the midline incision, the left lower incision allows for extraction of the colon segment with less tension, thus avoiding unnecessary bowel dissection and incision extension and may cause less pain for patients. Also, a midline incision could lead to higher morbidity and, particularly, incisional hernia as reported in a systemic review (22).

In recent years, the use of barbed suture has proven to be safe and efficient in urinary tract surgery (23), gynecological surgery (24), and gastrointestinal anastomosis (10, 11). Although multifilament absorbable suture was generally used for gastrointestinal anastomosis, since the application of barbed sutures, more and more surgeons prefer the knotless technique because of the lower operational difficulty, especially in total minimally invasive operations. Applying barbed suture in anastomosis can reduce the number of knots and results in less operation time.

In our series, the postoperative complications were comparable between KHEA and stapled anastomosis. As tension on the anastomosis and poor vascularization of the proximal colon limb are among the risk factors for anastomotic leakage (25), we believe that the KHEA technique might decrease the leakage rate. We found that less mobilization of the bowel is required for the KHEA technique, which might potentially reduce the risk of marginal vascular injury such as injury to Riolan's arch. Moreover, manual suturing may potentially reduce the incidence of anastomotic bleeding (26) because of a better view of the bowel mucosa.

Based on our experience, special attention should be paid to the cut end of the barbed suture material. We recommend cutting the end flush against the intestinal wall to prevent adherence to surrounding tissues, which are a potential source of intestinal obstruction.

We recognize certain limitations in our study. First, this was not a randomized controlled study. We performed propensity score matching to minimize the effects of potential biases due to preoperative patient characteristics. Second, all the health economics calculations were based on the Chinese medical system and might vary in different countries with different insurance policies. Third, we did not evaluate the long-term outcomes. Late-onset postoperative complications such as incisional hernias were not evaluated.

The KHEA technique is a safe, economical, convenient, and feasible anastomosis method for laparoscopic left hemicolectomy. This technique could substantially reduce hospitalization cost and operational time with comparable complication rates. It may also have more potential benefits because of the less range of bowel dissection and shorter abdomen incision.