RESEARCH
Researchers question whether lymph node removal may impair immunotherapy response — Colorectal Disease
A hypothesis-generating review examines whether routine lymphadenectomy (removal of ≥12 lymph nodes, a well-recognized quality indicator in colorectal cancer surgery) may theoretically impair systemic immune surveillance and immune checkpoint inhibitor (ICI) response. The authors reviewed surgical, oncological and immunological literature, including comparisons to breast cancer and melanoma where sentinel lymph node biopsy (SLNB) is used. The concern is most applicable to mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) disease. Contemporary immunology reframes tumor-draining lymph nodes (TDLNs) as active coordinators of anti-tumor immunity.
What this means
This is a hypothesis-generating perspective, not a clinical trial or recommendation to change current surgical practice. However, it raises an important question for future research: in the era of immunotherapy, particularly for MSI-H/dMMR colorectal cancer, could removing fewer lymph nodes preserve immune function while maintaining cancer control? This concept is being explored in breast cancer and melanoma but remains theoretical in colorectal cancer.