What is melanoma?
Malignant melanoma is a rare type of skin cancer that may spread and affect other organs of the body. Malignant melanoma may start in a pre-existing mole but may also appear in healthy looking skin.
Malignant melanoma causes most skin-cancer related deaths and yet remains relatively rare, over exposure to the sun, sun beds, and sun lamps are believed to be a direct cause of the development of skin cancers.
Melanoma diagnosed and treated in its earliest stages has an excellent prognosis and a high cure rate, in advanced melanoma the prognosis is poor and a total cure unlikely.
The treatment of patients with
often results in the formation of new cancers due the use of the drugs known as BRAF inhibitors. Studies have previously shown that up to 30% of skin cancer patients treated with BRAF inhibitors have gone on to develop cutaneous squamous cell carcinoma – a skin cancer requiring surgical removal.
Treatment of melanoma is generally carried out by a multi-disciplinary team of health care professionals working together to decide on the best course of treatment and to ensure it is carried out efficiently and effectively. The type of treatment available will very much depend on the stage the melanoma has reached, the type of cancer it is and your overall general health. The final decision regarding any treatment is entirely left up to the patient involved.
Squamous cell carcinoma
In a small study of twenty-one patients with malignant melanoma, all of whom had been treated with vemurafenib in a previous clinical trial, it was discovered that 60% of their tissue samples contained cancer-causing mutations. Further testing did show that BRAF inhibitors were not responsible for triggering development of squamos cell carcinomas but that they did increase the rate and development of existing cancerous changes in skin not yet showing symptoms. Studies carried out on mice showed that an alternate inhibitor was able to reduce and slow down the development of secondary tumours even in the presence of BRAF inhibitors.
The aim of this study was to ensure that more patients could benefit from the use of BRAF inhibitors in the treatment of their cancer. Determining how secondary tumours develop in the 30% if melanoma patients adversely affected by BRAF inhibitors means that the development of secondary tumours can be reduced without reducing the benefits of drugs containing BRAF inhibitors.
This understanding of how a cancer treatment side effect works and develops is particularly important since it is the first time it has been molecularly understood how the drug works in an alternate cellular setting. In one type of cancer, the drug limits the growth of the malignancy; in the other, it encourages growth.
It is believed that this research will lead to improved methods of avoiding the secondary skin cancers affecting some patients prescribed with BRAF inhibitors – ongoing research and further clinical trials will discover whether the new combination of drugs will be useful in treating the original melanoma whilst preventing the development or formation of new cancers.