Selective lymphadenectomy in sentinel node-positive patients may increase the risk of local/in-transit recurrence in malignant melanoma.

Aim: To determine whether sentinel lymph node biopsy (SLNB) for cutaneous malignant melanoma, particularly when followed by selective lymphadenectomy (SL) if involved nodes are found, alters the incidence of local/in-transit recurrence.
Methods: A literature overview of SLNB with or without SL has been performed, concentrating on the reported site(s) of first recurrence, and with specific reference to the incidence of local/in-transit recurrence. This is compared to the incidence after wide local excision (WLE) alone.
Results: The incidence of local/in-transit recurrence after WLE alone is 2.5-6.3% over a given range of tumour thickness, and is 9.0% after SLNB (with or without SL). In the latter group, the local/in-transit recurrence rate is 5.7% following SLNB alone in SN-negative patients, and is 20.9% after SLNB plus SL in SN-positive patients.
Conclusions: The incidence of local/in-transit recurrence following selective lymphadenectomy in sentinel node-positive patients may be greater than four times the incidence expected. This possible iatrogenic risk should be confirmed or refuted by randomised controlled trial. Until then the SLNB procedure should be regarded as experimental and not performed outside validation trials.