ABSTRACT
The controversy surrounding the surgical management of the regional lymph nodes in earlystage melanoma began over a century ago. In 1892, Herbert L Snow,1 in his lecture “Melanotic Cancerous Disease,” advocated wide excision and elective lymph-node dissection as a method to control lymphatic permeation of metastases. His recommendation that treatment of melanoma routinely include excision of the draining lymph nodes was based upon his studies suggesting a direct connection of the primary tumor with the regional lymph nodes. Elective lymph-node dissection for patients with early-stage melanoma has remained controversial since Dr Snow first proposed this management approach. While many retrospective studies suggest a survival benefit for patients undergoing this procedure compared with those for whom initial treatment is limited to removal of the primary tumor alone, the
therapeutic benefit of removing clinically normal lymph nodes has never been proved by randomized prospective studies.2-12 Although elective lymph-node dissection is considered a valuable staging procedure, the cost, morbidity, inaccuracy of predicting patterns of metastases, and overall low yield of tumor-containing nodes with this procedure have led most surgeons to abandon it as a routine part of patient care. Yet, the tumor status of the regional lymph nodes has become exceedingly important for determining prognosis and directing the use of adjuvant therapy.13,14
As a result of their dissatisfaction with the elective procedure, Morton and associates developed the technique of intraoperative lymphatic mapping and sentinel lymph-node biopsy. This minimally invasive procedure allows the surgeon to map the route of lymphatic permeation from the primary to the
The John Wayne Cancer Institute technique for SLN biopsy in melanoma
Technique Combination Isotope Type: Various Filtered: Yes (0.2-m filter)
Dye Type: Isosulfan blue dye Dose: 0.5-0.8 mCi (18.5-30 MBq)
Volume: 0.5-1.0 ml (cc) Volume: 0.5-1.0 ml (cc)
Injection site Isotope: Intradermal Dye: Intradermal
regional lymph nodes and then selectively excise the first or “sentinel” nodes. Because the sentinel lymph node (SLN) has been shown to be the most likely site for metastases, focused pathologic examination of the SLN leads to accurate staging of the lymph-node basin. Patients with metastases undergo complete lymph-node dissection, while those without metastases are spared the expense and morbidity of complete lymph-node dissection.
