Lymphatic mapping improves staging during laparoscopic colectomy for cancer

Area of Science:

• Surgical Oncology
• Gastroenterology
• Diagnostic Imaging

Background:

• Sentinel lymph node (SN) biopsy with ultrastaging aids in diagnosing colorectal cancer (CRC) micrometastases.
• A novel technique for laparoscopic lymphatic mapping (LM) during laparoscopic colon resection (LCR) has been developed.

Purpose of the Study:

• To evaluate the feasibility and utility of laparoscopic lymphatic mapping (LM) during laparoscopic colon resection (LCR) for early-stage colorectal cancer (CRC).
• To assess the accuracy of LM in identifying sentinel lymph nodes (SNs) and detecting micrometastases.

Main Methods:

• 11 patients with early-stage CRC underwent laparoscopic LM and LCR.
• Tumor sites were marked preoperatively with carbon dye or intraoperatively with isosulfan blue dye.
• Laparoscopic visualization followed blue-stained lymphatic channels to identify and mark SNs.

Main Results:

• Laparoscopic LM successfully identified 1-3 SNs per patient in all 11 cases.
• LM added approximately 15-20 minutes to the operative time.
• SNs accurately reflected overall nodal status; micrometastases were detected in one node-positive case via CK-IHC.
• LM revealed unexpected lymphatic drainage in four cases, leading to adjusted resection margins.

Conclusions:

• Laparoscopic LM during colectomy for CRC can effectively mark the primary tumor and delineate lymphatic drainage, potentially altering resection margins.
• Focused examination of SNs identifies occult micrometastases, improving CRC staging accuracy.