Research "You’ve got melanoma skin cancer," are words no one wants to hear. Unfortunately more and more of us are receiving this diagnosis. The incidence of malignant melanoma – the most dangerous form of skin cancer - has quadrupled over the last 30 years. If this rate of increase carries on, within 15 years we may have 15,500 people a year diagnosed with malignant melanoma.
An important new development in the treatment of the condition may mean that those diagnosed with malignant melanoma have a better chance of beating the disease. Or, at least, living for longer with it, and feeling better for longer.
Clinical trials with an experimental new drug currently named PLX4032 - have had exciting results. It has shrunk tumours in 28 out of the 32 patients in the second stage of the trial. Most of the patients had metastatic melanoma, where the cancer has spread to other parts of the body
The drug works by targeting a faulty gene that is present in the tumours of 40 to 60 percent of melanoma patients. The gene contains a protein called BRAF, which is overactive in more than 50 percent of melanomas and promotes cell growth in the tumour. PLX4032 inhibits the gene and tumour growth.
It was a relatively small trial, but the results could make a big difference to the treatment of melanoma. Forty nine melanoma patients took part in the first phase, and 32 with metastatic melanoma (melanoma which has spread), took part in an extension phase. In total, tumours shrank in 37 patients and in three they disappeared.
"One of the things that makes these results truly remarkable is that this drug works so reliably," explains Keith Flaherty, MD, director of Developmental Therapeutics at the Massachussets General Hospital (MGH) Cancer Center. "And patients who have been experiencing symptoms like pain and fatigue begin to feel better within a week of starting treatment, giving them a much better quality of life."
As has happened with previous trials of this kind, using targeted cancer treatment, some of the patients taking part developed a resistance to PLX4032, and their tumours started to grow again. Nonetheless, this is still a big step forward in skin cancer treatment. One of the next steps in the continuing battle will undoubtedly be to tackle this problem.
"Until now, we’ve never had a credible first treatment option for metastatic melanoma, so this has completely transformed how we approach treatment for patients with the BRAF mustation," says Flaherty, who is a member of the Harvard Medical School faculty. "Although we don’t know how long response may last, the ability to beat this disease down in the short term will buy us time to strategise second-line therapies and design the next generation of trials."
"These results are extremely exciting," said Professor Richard Marais, Cancer Research UK’s melanoma expert at The Institute of Cancer Research. "This is the first time in over 30 years that this level of response has been seen in melanoma patients in any clinical trial.
"While these results are very promising, there is still work to be done. Although patients initially respond they can often relapse during treatment, so now we need to learn how to get longer-lasting responses in these patients."
Useful websites
Cancer Research UK - www.cancerresearchuk.org
Sun Smart - www.sunsmart.org.uk