Sentinel node biopsy and selective dissection for melanoma nodal metastases

Early detection of nodal metastases still represents an important goal in the management of melanoma patients. A sentinel node is defined as the first colored node in the regional lymphatic basin following injection of blue dye in the site of the primary melanoma. Sentinel node biopsy may represent a feasible technique for early identification of occult disease. A therapeutic dissection is then performed only in patients with proven nodal disease, thus introducing the concept of selective dissection.

At the National Cancer Institute of Milan from February 1994 to October 1996, 74 patients with a melanoma of the trunk or limbs and without clinically detectable node metastases were submitted to sentinel node biopsy and eventual selective dissection.

The sentinel node was identified in 67 patients (90%). Nodal metastases were detected in 11 patients (16%); 5 of these were identified by an intraoperative frozen section examination. In all but one case, only the sentinel node was affected at radical dissection. Incidence of positive sentinel nodes was correlated with depth of infiltration of the primary lesion. Mapped nodal basin failures were observed in 3 patients with negative sentinel node biopsy. All patients but one, presenting distant metastases, are alive at this writing and free of disease with a follow-up ranging from 2 to 34 months.

Our study adds to accumulating evidence supporting the efficacy of sentinel node biopsy in detecting occult localizations and the potential of the technique to better select the group of patients that may benefit from nodal dissection.