Objective. The aim of this study was to evaluate short-term outcomes of performing intracorporeal versus extracorporeal anastomosis in laparoscopic right hemicolectomy for right colon neoplasm. Background. Despite advances in laparoscopic approach in colorectal surgery and the clear benefit of this approach over open surgery, the technical difficulty in performing intracorporeal anastomosis causes certain groups continue performing it extracorporeally in right colon surgery.

Methods. This study was a prospective multicenter randomized trial with two parallel groups being done intracorporeal anastomosis (IA) or extracorporeal anastomosis (EA) in laparoscopic right hemicolectomy for right colon neoplasm, carried out between January 2016 and December 2018.

Right hemicolectomy using a minimally invasive technique allows for an earlier recovery, with less postoperative pain and less hospital stay. After right hemicolectomy, the ileocolic anastomosis is not performed "naturally" as is habitually done in low anterior resections or sigmoidectomies. There is, therefore, no standardization in the reconstruction technique, with two possibilities: intracorporeal and extracorporeal anastomosis.

The intracorporeal anastomosis allows proper visualization of it, ensuring adequate conformation (absence of rotation or traction), in addition allowing the closure of the mesos and avoiding the possible appearance of internal hernia, also allowing to choose the location and length of the incision necessary for the extraction of the piece. On the other hand, it is a difficult technique that requires high training in advanced laparoscopy.

The extracorporeal anastomosis is performed by extracting both ends (terminal ileum and transverse colon) through the incision through which the piece is obtained, and the anastomosis is performed. It does not require, therefore, an important training in intracorporeal sutures. On the contrary, it forces to make the abdominal incision in the area that allows the extraction of said ends. In obese patients it can be difficult since the mesos are short and do not allow their extraction easilywith ,so sometimes, it forces excessive traction. In addition, intestinal rotations during the anastomosis may go unnoticed.

Although there are currently defenders of both techniques, the extracorporeal anastomosis is currently the most performed in our environment and will be used as a reference treatment in the present study.

Numerous studies have been published comparing both techniques. A very recent meta-analysis, including 12 non-randomized comparative studies with 1492 patients, concluded that intracorporeal anastomosis is associated with less morbidity and a reduction in hospital stay, suggesting a faster recovery. To date, no well-designed, prospective, randomized and randomized study exists in the literature. We believe it is necessary, therefore, to carry out a project that compares both surgical techniques in the treatment of right colon cancer and assess which is associated with a lower postoperative morbidity.

Inclusion Criteria:

• All patients had to be 18 years of age or over, to be programmed for laparoscopic surgery for right colon neoplasm and provide a signed written consent form.

Exclusion Criteria:

• All patients who do not meet all the inclusion criteria were excluded. The other exclusion criteria included the need for emergency surgery, renal failure defined by haemodialysis, Crohn's disease, ulcerative colitis, T4 tumor invading adjacent organs, synchronous colorectal neoplasm, metastasis or carcinomatosis at diagnosis, bowel obstruction, psychiatric disorders or contraindication for laparoscopic approach.