Development of a Visual Analogue Scale for Lymphadenectomy in Right-Sided Colectomy

Overview

A novel visual analogue scale (VAS) based on vascular anatomy was developed to objectively quantify the extent of lymphadenectomy in right-sided colon cancer surgery. This prospective observational study involving 155 patients demonstrated that the VAS correlates with surgeon classification, specimen quality, and lymph node harvest, addressing the variability in defining lymphadenectomy extent.

Background

Right- and left-sided colon cancers differ in embryological origin, molecular profiles, and vascular anatomy, with right-sided cancers presenting more complex vascular structures. Central lymphadenectomy, particularly complete mesocolic excision (CME), has been linked to improved survival but lacks standardized definitions. Current classifications such as Japanese D3 and European CME vary, complicating comparisons and consensus. Norway’s national guidelines recommend a 'complete D2' dissection along the right border of the superior mesenteric vein (SMV), but definitions of D3 dissection remain inconsistent.

Data Highlights

Key Findings

• The VAS integrates preoperative CT imaging, intraoperative findings, and vascular anatomy to quantify lymphadenectomy extent.
• VAS scores correlate with surgeon categorical classifications (D2, cD2, CME, D3), providing objective measurement.
• Higher VAS scores associate with improved visualization of mesenteric vessels and higher quality surgical specimens.
• Extensive lymphadenectomy as measured by VAS corresponds to increased lymph node harvest.
• The scale addresses variability and lack of consensus in defining lymphadenectomy extent in right-sided colon cancer surgery.

Clinical Implications

The VAS offers surgeons an objective tool to standardize reporting and assessment of lymphadenectomy extent, potentially improving surgical quality and oncological outcomes. It may facilitate clearer communication and comparison across institutions and studies, supporting tailored surgical approaches. Adoption of the scale could enhance adherence to guidelines and optimize patient selection for radical lymphadenectomy.

Conclusion

The novel visual analogue scale based on vascular anatomy provides a reproducible and objective method to assess lymphadenectomy extent in right-sided colon cancer surgery, addressing current inconsistencies and supporting improved surgical standardization.

References

1. Japanese Classification and European CME Definitions
2. Bertelsen et al. -- CME and Long-term Survival
3. RESECTAT Trial -- CME and Disease-Free Survival
4. RELARC Study -- CME in Stage III Colon Cancer
5. Norwegian National Guidelines on Lymphadenectomy
6. Systematic Review on Radical Right-Sided Colon Surgery Variability
7. Osirix 3D Reconstruction and VAS Development
8. Randomized Trial Comparing Open D3 and Laparoscopic CME