BUENOS AIRES--The surgical care of the melanoma patient is in
flux because of new data showing that complete nodal staging can
be obtained with the technique of lymphatic mapping and sentinel
lymph node biopsy, said speakers at a plenary session at the Sixth
World Congress on Cancers of the Skin.
Douglas Reintgen, MD, of the Moffitt Cancer Center, Tampa, Fla,
explained that the concept is based on the belief that lymphatic
drainage is not a random event, but that the precise node that
drains an area of skin can be identified.
The sentinel lymph node is defined as the first node in the lymphatic
basin into which the primary melanoma drains, and reports from
four centers (John Wayne Cancer Institute, Moffitt Cancer Center,
M.D. Anderson Cancer Center, and the Sydney Melanoma Unit) have
shown that the histology of the sentinel lymph node reflects the
histology of the remainder of the nodal basin.
With the lymphatic mapping technique, only patients with solid
evidence of nodal metastatic disease, those with a positive sentinel
lymph node, are subjected to the expense and morbidity of a complete
This strategy of selective lymphadenec-tomy would seem to satisfy
both the proponents and critics of the previous nodal staging
procedure--elective lymph node dissection. All patients would
undergo complete pathologic staging of their lymphatic basins,
and most would be spared a complete lymph node dissection.
The first step with this technique involves lymphatic mapping
via preop-erative lymphoscintigraphy--the injection of a radiocolloid
around the primary melanoma site--with imaging of the afferent
lymphatics and the regional nodal basin (see figure).
Intraoperative lymphatic mapping to harvest the sentinel lymph
node for biopsy is then performed using either a vital blue dye
or a radiocolloid.