Results of an EORTC study show that vaccination with GM2/KLH-QS-21 does not benefit patients with stage II melanoma. Vaccination with GM2/KLH-QS-21 stimulates the production of antibodies to the GM2 ganglioside, an antigen expressed by many melanomas. Serological response to GM2 was shown to be a positive prognostic factor in patients with melanoma and was the rationale for this trial.
The idea of treating cancer with a vaccine has been around since the first vaccines against infectious disease were developed. The GM2 ganglioside, an antigen expressed in most melanomas but with limited expression in normal tissues, was thought to offer a suitable target for such therapeutic vaccination. Previous studies had shown that serological response against GM2 was a favourable prognostic factor. The five and ten year survival rates for patients with melanoma having primary tumours with a Breslow thickness greater than 1.5 mm are just of 74% and 61%, respectively, so EORTC trial 18961 was launched to compare vaccination to observation in these patients.
Prof. Alexander M.M. Eggermont of the Institut Gustave Roussy, Villejuif, Paris-Sud, and Universit