In the sentinel lymph node biopsy (SLNB) procedure for malignant melanoma, which combination of mapping agents provides the highest detection rate of the sentinel node?
- A Patent blue dye alone
- B Technetium-99m nanocolloid radioisotope alone with gamma probe
- C Combined technique: blue dye + radioisotope (Tc-99m) with gamma probe ✓
- D ICG (indocyanine green) fluorescence imaging alone
Explanation
The combined technique using both patent blue dye (visual identification of stained lymphatics) and technetium-99m labelled nanocolloid (with intraoperative gamma probe) achieves the highest sentinel node detection rate (~98–99%) compared to either modality alone (patent blue ~85%, radioisotope ~93%). The MSLT-I trial validated SLNB accuracy and its prognostic significance in melanoma. ICG fluorescence is an emerging technique with comparable results in experienced centres but is not yet universally the standard dual-agent replacement. Failure to identify the SLN by either technique alone prompts use of the combined technique.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.