Sentinel node procedure increases survival chances of skin cancer patients

Early detection, and in some cases removal, of metastases in the lymph nodes – the sentinel node procedure – improves the eventual survival chances of patients with an aggressive form of skin cancer (melanoma). This has been revealed by international research (US, Canada, Australia and Europe) conducted on over 2000 melanoma patients. The results were published this week in the New England Journal of Medicine. The UMCG is one of the two participating Dutch centres.

Melanoma is a particularly aggressive form of skin cancer that is diagnosed each year in about 6000 patients in the Netherlands. The sentinel node procedure is a low-burden surgical technique to establish the presence or absence of metastases in the lymph nodes.

Sentinel node procedure

During this procedure, the first draining lymph node (the sentinel node) is detected with a low-activity radioactive substance and a dye. This node is then removed and investigated for cancer cells. If a melanoma has metastasized, this will nearly always be via the lymphatic system. The disease can then spread further from the sentinel node. If no tumour cells are discovered in the sentinel node, the other lymph nodes do not need to be removed. The removal of the sentinel node has no lasting effect on the patient.

Higher survival rate with sentinel node procedure

The research reveals that the 10-year illness-free survival rate of patients with a melanoma that is 1.2 - 3.5 mm thick, whereby no lymph node metastases were present during the sentinel node procedure, was 85%. If lymph node metastases were present this rate was 62%. The 10-year illness-free survival rate of patients who did not undergo the sentinel node procedure and developed lymph node metastases was 41.5%. The sentinel node procedure with thicker melanomas provides information about the prognosis and contributes to better tumour control, but is not linked to a better survival rate.

In the Dutch melanoma guidelines, the advice is currently to reserve the sentinel node procedure for patients who wish to be as well informed as possible about their disease and the prognosis. In the Netherlands, fewer than 50% of the patients who would qualify for the sentinel node procedure actually undergo it.

• NEJM publication
• NEJM editorial