The purpose of this study is to evaluate the effectiveness of transanual tube placement in low anterior resection (LAR) for rectal cancer in preventing anastomotic leakage.

Transanual tube placement after anastomosis in low anterior resection for rectal cancer.

Inclusion Criteria:

1. Age ≥ 18 and ≤ 75 years;
2. Primary tumor has undergone histologically confirmed rectal adenocarcinoma; Low rectal cancer was defined by the presence of the inferior pole of the tumor below the peritoneal reflection (in 11 cm from the anal margin).
3. Together with clinical or radiological evidence of Stage II (T3-4, N0, M0) or Stage III (T1-4, N1-2, M0) disease (according to the 2010 revision of the International Union Against Cancer primary tumor, regional nodes, metastasis (TNM) staging system).
4. Performance status (ECOG) 0~1
5. Adequate hematological function: Neutrophils≥1.5 x109/l and platelet count≥100 x109/l; hemoglobin (Hb) ≥9g/dl (within 1 week prior to randomization)
6. Adequate hepatic and renal function: Serum bilirubin≤1.5 x upper limit of normal (ULN), alkaline phosphatase ≤5x ULN, and serum transaminase (either primary tumor, regional nodes, metastasis (AST) or ALT) ≤ 5 x ULN(within 1 week prior to randomization);
7. Written informed consent for participation in the trial.

Exclusion Criteria:

1. Body mass index (BMI) more than 30 kg/m2.
2. Serious pre-operative comorbidity, including cardiovascular disease (coronary arteriosclerosis, arrhythmia, heart failure), pulmonary dysfunction (lung emphysema, obstructive lung disease), liver insufficiency (Child-Pugh B or C), renal insufficiency (serum creatinine >2.0 mg/dl), and arterial circulation disturbance (occlusion of arterial vessels of limb in patient's history.
3. History of accepting abdominal surgery.