[Sentinel lymph node procedure in melanoma patients: a staging procedure, not a therapy]

The definitive results of the MSLT-1 study in melanoma patients were published recently. The sentinel lymph node (SLN) procedure shows no survival benefit compared with observation. The authors reported, however, that there was a survival benefit with "biopsy management" of patients. This statement is based on subgroup analyses that we find to be incorrect for three reasons: (a) patients with a false negative SLN were incorrectly left out of consideration; (b) accelerated failure time latent subgroup analysis is an unproven statistical hypothesis, which was developed on interim data from the MSLT-1 study, and therefore cannot be used as validation; (c) there is a significant difference in terms of the percentage of patients with affected lymph nodes between the SLN group and the observation group. This excess of "prognostic false positive" patients would have incorrectly falsely improved the survival of the SLN group. We concluded that the SLN procedure does not give a survival benefit and that its role in melanoma patients should be for staging purposes and not for therapeutic purposes.