Left Hemicolectomy with D3 Lymphadenectomy: Evidence‑Based Guidelines

Preoperative Assessment

Colonoscopy is required to locate the tumor and exclude synchronous lesions (American Society of Colon and Rectal Surgeons) 1
Contrast‑enhanced CT of the chest, abdomen, and pelvis should be performed to detect distant metastases and delineate tumor extent (American Society of Colon and Rectal Surgeons) 1
Baseline laboratory work‑up—including carcinoembryonic antigen, complete blood count, and routine biochemistry—is recommended (American Society of Colon and Rectal Surgeons) 1
MRI is advised when the disease is locally advanced to better characterize involvement of adjacent structures (American Society of Colon and Rectal Surgeons) 1

A laparoscopic approach is recommended when surgical expertise is available, as it reduces morbidity while providing oncologic outcomes comparable to open surgery (American Society of Colon and Rectal Surgeons) 1
The operative goal is to harvest at least 12 lymph nodes to ensure accurate pathological staging (American Society of Colon and Rectal Surgeons) 1

TNM staging must follow the UICC classification system (American Society of Colon and Rectal Surgeons) 1
Pathology should assess high‑risk features such as lymphovascular invasion, perineural invasion, poor differentiation, and insufficient nodal harvest (American Society of Colon and Rectal Surgeons) 1
Microsatellite instability (MSI) or mismatch repair (MMR) status should be determined in stage II disease to guide adjuvant therapy decisions (American Society of Colon and Rectal Surgeons) 1

Harvesting fewer than 12 lymph nodes is associated with understaging and is considered a high‑risk factor that may necessitate adjuvant therapy (American Society of Colon and Rectal Surgeons) 1
Omitting D3 lymphadenectomy in T3/T4 tumors compromises oncologic outcomes; Asian guidelines recommend routine extended lymphadenectomy for such advanced tumors (American Society of Colon and Rectal Surgeons) 1
Inadequate resection margins jeopardize oncologic adequacy (Praxis Medical Insights) 3