Some doctors think the latest cancer treatment could mean a new era in tackling the disease.
It uses 2 different drugs to wake up the body's own immune system, which then starts attacking cancerous cells.
A trial showed more than half of patients with advanced melanoma had their tumours shrink or brought under control as a result.
Doctor Anthony El-Khoueiry, from the American Society of Clinical Oncology, explains the success of the trials:
