Sentinel lymph node biopsy is used in clinically lymph node negative, primary cutaneous melanoma. A combination of planer lymposcintigraphy using a radiolabelled colloid detected intra-op by gamma probe, and cutaneous injection of blue dye is used. However, with lymphoscintigraphy spillage of the carbon dated colloid or failure to detect the colloid with the gamma probe isn’t uncommon, and blue dye has a high false negative rate. The authors recorded the time taken by consultants/senior SPR at a single site to locate and excise sentinel nodes cohort of 47 patients.
The mean time was six minutes compared to 65 minutes recorded elsewhere in the literature. Mean number of nodes excised per nodal basin was similar to the literature, and all sentinal nodes were located and excised.
Only 55% of nodes were dyed blue (similar to published literature) raising the question of whether blue dye is a useful adjunct in this procedure. The authors’ experience was that SPECT-CT reducing the time to excise all sentinel nodes and detecting nodal basin involvement in two patients not identified by scintigraphy. It was found to be particularly helpful in the head and neck region and the authors proposed that the anatomical intricacies in this area make focused dissection even more essential to avoid inadvertent tissue damage or resection. The additional cost and time and resource implications of additional imaging must be weighed up against potential conferred benefit. The authors did not comment on how they verified that ‘all’ sentinel nodes had been excised by this method, and how important operator experience was in gaining the time-saving benefit of this technique.
