Sentinel node biopsy for melanoma: unnecessary treatment?

In 2006 a hotly anticipated paper on melanoma treatment was published in the New England Journal of Medicine. The paper unveiled the five year results of the Multicenter Selective Lymphadenectomy Trial (MSLT-I), a trial designed to determine whether using sentinel lymph node biopsy to detect early nodal spread provided a window of opportunity for wider lymphadenectomy to improve survival.1

The trial was seen as a ray of hope because, while other much rarer cancers had potential treatments in development, no interventions had been shown to produce a survival advantage in melanoma.

Melanoma is the fifth most common cancer in the UK and the incidence is rising—one in 60 people can expect to develop melanoma during their lifetime2; in the United States it is one in 50.3 Of the seven most common cancers in the US, melanoma is the only cancer whose incidence is increasing.3

These figures are concerning because we still do not have effective adjuvant treatment. Early diagnosis of the primary tumour is still the best opportunity for cure by surgical resection. Five year median survival is 92% for stage I disease, 40-45% for stage III disease (when it has spread to the lymph nodes), and 5-15% with metastasis to distant organs, where median survival without treatment is 6-9 months.3

MSLT-I, led by Donald Morton at the John Wayne Cancer Institute in the US, was expected to show that sentinel node biopsy and early lymphadenectomy for patients with positive nodes conferred a survival advantage over observation and removal of the affected nodes once they became palpable.

A total of 2001 patients were randomised between 1994 and 2002, …