The goal of this observational study is to evaluate whether different circular stapling devices influence the success of the surgical connection between the bowel ends after colorectal cancer surgery in patients undergoing colorectal resection using different stapling devices.

The main question this study aims to answer is whether different circular stapling devices affect the risk of a leak developing at the site where the bowel is reconnected after colorectal cancer surgery.

Researchers will compare three types of circular stapling devices commonly used in clinical practice (two-row, three-row, and powered circular staplers) to determine whether they are associated with different risks of leakage at the site where the bowel is reconnected after colorectal cancer surgery.

Participants will receive standard medical care. Taking part in this study will not affect their treatment, and no additional procedures, tests, or visits are required as part of the study.

Inclusion Criteria:

• Adult patients (18 years or older)
• Patients undergoing elective surgery, either open or minimally invasive (laparoscopic or robotic), for anterior rectal resection, sigmoid resection, or left hemicolectomy for colorectal cancer with concomitant colorectal anastomosis (Knight-Griffen technique) using one of the circular stapler types under investigation (two-row CS, three-row CS, PCS).

Exclusion Criteria:

• Patients undergoing emergency surgery
• Patients undergoing additional surgical procedures during the same operation (e.g., cholecystectomy, liver resection, etc.)
• Patients with documented metastases at preoperative staging (cM+)
• Patients under 18 years of age
• Lack of informed consent

The study population consists of patients undergoing elective colorectal resection with primary colorectal anastomosis for colorectal cancer at participating centers. Participants will be recruited from multiple italian and international hospitals involved in this multicenter observational study.