The problem of anastomotic leak is particularly relevant in rectal surgery. Many risk factors have been recognized in the onset of this complication. Preventing the anastomotic leak can bring benefits to the patient and the health system.

Several attempts have been proposed to reduce the risk of anastomotic leakage in rectal cancer surgery including suture protection with omental flap and external suture reinforcement by biological glue or mesh.

Cyanoacrylate (Glubran 2®) is a synthetic glue with sealing, adhesive and hemostatic properties widely used in surgery. The sealing effect creates an antiseptic barrier against bacteria.

The hypothesis is that the application of nebulized cyanoacrylate to the colo-rectal anastomosis in open or laparoscopic/robotic rectal surgery can prevent the leakage

Colorectal cancer (CRC) is the second most common cause of cancer-related death in male and the third in females in Western Countries accounting for more than 500,000 deaths in 2013 worldwide.

One of the most worrying postoperative complication in colorectal surgery is the anastomotic leak which can occur in about 10-15% of the cases.

This complication severely impact clinical outcomes with increased risk of death or permanent stoma, higher risk of local recurrence) and relevant increase in hospital costs (length of hospital stay, admission to intensive care, re-interventions).

The problem of anastomotic leak is particularly relevant in rectal surgery. The more distal the anastomosis, the higher the likelihood of failure, with resection of a distal rectal cancer having almost a five-fold increased risk of anastomotic leak compared with resection for colon cancer.

In fact, anastomotic Leakage (AL) is the most severe complication after Low anterior resection of rectum for cancer, occurring between 3 and 24 % of patients.

Many risk factors have been recognized in the onset of this complication, including gender (male patient have a higher anastomotic leak rate), malnutrition, obesity an diabet, american society anesthesiologists (ASA) score, tobacco use, cardiovascular disease, immunosuppression, use of NSAID, preoperative pelvis radiation.

Other intraoperative risk factors considered are the splenic flexure mobilization with proximal ligation of the inferior mesenteric artery (IMA), positive intraoperative Air-Leak Test and the perfusion of the anastomosis.

Temporary fecal diversion has also been suggested (although a diverting stoma mitigates the clinical consequences of an anastomotic leak but does not prevent it.

Other intraoperative technical factors include the use of single or double stapled anastomotic techniques, with or without transanal reinforcing sutures.

Therefore, preventing the anastomotic leak can bring benefits to the patient and the health system.

All the risk factors described above represent the rationale that justifies the use of intraoperative procedures to prevent the anastomotic leak, such as additional manual stiches to the mechanical suture and / or patches of collagen (proper reinforcement or buttressing) or of sealants.

Several attempts have been proposed to reduce the risk of AL in rectal cancer surgery including suture protection with omental flap and external suture reinforcement by biological glue or mesh.

Some Authors have reported good results of reinforcement of the colon anastomosis with cyanoacrylate glue. in a porcine model.

Cyanoacrylate is a synthetic glue with sealing, adhesive and haemostatic properties widely used in surgery. Furthermore the sealing effect creates an antiseptic barrier against bacteria.

Several clinical studies have described the utility of cyanoacrylate glue mainly in vascular surgery, urology and bariatric surgery.

Considering its mechanical, physical, biological properties and its safety, cyanoacrylate glue could facilitate the healing of the colorectal anastomosis reducing leak rate, without negative effects on perfusion.

The hypothesis is that the application of nebulized cyanoacrylate to the colo-rectal anastomosis in open or laparoscopic/robotic rectal surgery can prevent the leakage

Inclusion Criteria:

• Resectable, histologically proven primary adenocarcinoma of the High-medium rectum without internal and/or external sphincter muscle involvement.
• Distal margin of the tumor at least 8 cm form the anal verge
• Staged as follows prior to neoadjuvant chemoradiation: Stage T2 - T4 at MRI
• Patient classified T3-T4 will undergo neoadjuvant chemoradiation if the cancer is located in the extraperitoneal rectum

Exclusion Criteria:

• Squamous cell carcinoma
• Adenocarcinoma Stage T1,
• T4 with one of the following: with pelvic side wall involvement, requiring sacrectomy, requiring prostatectomy (partial or total)
• Unresectable primary rectal cancer or Inability to complete R0 resection.
• Rectal cancer under 8 cm from the anal verge requiring colo-anal or ultra low rectal anastomosis
• Recurrent rectal cancer
• Previous pelvic malignancy
• Inability to sign the informed consent