Laparoscopic IIeocecus-Sparing Right Hemicolectomy for Cancer of the Hepatic Flexure and Proximal Transverse Colon

Inclusion Criteria: 1. Patients suitable for curative surgery 18-75years old 2. ASA grade I-III 3. Qualitative diagnosis: a pathological diagnosis of adenocarcinoma; 4. Localization diagnosis: the tumor located at hepatic flexure and proximal transverse colon(proximal to the right branch of middle colic artery); 5. Enhanced CT scan of chest, abdominal and pelvic cavity: assessment of tumor stage is T1-T4N0 or TanyN+; there is no distant metastasis. 6. Intraoperative measurement: the distance between colic branch of ileocolic artery and proximal edge of the tumor should be longer than 5cm. 7. Informed consent Exclusion Criteria: 1. Simultaneous or metachronous multiple primary colorectal cancer; 2. History of familial adenomatous polyposis, ulcerative colitis or Crohn's disease. 3. Preoperative imaging examination results show: fused lymph node at the root of ileocolic artery. 4. Distant metastasis. 5. History of any other malignant tumor in recent 5 years. 6. Patients need emergency operation. 7. Not suitable for laparoscopic surgery (i.e., extensive adhesion caused by abdominal surgery, not suitable for artificial pneumoperitoneum, etc). 8. Informed consent refusal