Betacyanin for Early Diagnosis and Recovery of Anastomotic Leakage After Rectal Cancer Surgery: A Single-Center, Prospective, Controlled Trial

Inclusion criteria

• Pathologically confirmed rectal adenocarcinoma prior to surgery.
• Undergoing laparoscopic anterior resection for rectal cancer.
• No prophylactic diverting ileostomy.
• American Society of Anesthesiologists (ASA) Physical Status Classification ≤ 3.
• No prior history of malignant tumors, and no evidence of other malignancies on preoperative examination.
• Written informed consent obtained from the patient or a legally authorized representative.

Exclusion criteria

• Prior abdominal surgery with severe intra-abdominal adhesions.
• Currently participating in, or having participated within the past 6 months in, another clinical study related to rectal cancer surgery.
• Preoperative complications requiring emergency surgery, including bleeding, perforation, or obstruction.
• History of prior malignancy.
• Undergoing Parks procedure with anastomosis at the anal verge, or Miles procedure, or Hartmann's procedure.
• Preoperative neoadjuvant chemoradiotherapy, or presence of other high-risk factors for anastomotic leakage requiring a prophylactic diverting ileostomy.
• ASA Physical Status Classification > 3.
• Patient withdrawal of consent.