National Skin Cancer Awareness Month
Last updated 4/20/2016 at 10:04am
Borrego Springs resident Dr. Hubert Greenway, who is chair of dermatologic surgery at Scripps Clinic, has an insight on the treatment of melanoma.
Advances in Melanoma Treatment More than Skin Deep
May is National Skin Cancer Awareness Month, and as summer approaches, it’s a smart time to learn about the significant advances being made against the deadliest form of the disease – melanoma.
The American Cancer Society estimates that in the United States this year, approximately 76,380 new melanomas will be diagnosed and about 10,130 people will die from the disease.
Incidence of new melanoma cases has risen steadily in the U.S. in recent decades, yet the 10-year survival rate has remained relatively stable. This is due in part to better participation in screenings, which helps doctors catch and treat melanoma early, when cure rates are strongest. However, when melanoma “metastasizes,” or spreads to other parts of the body, survival rates have historically dropped off significantly.
But the landscape of melanoma treatment has begun a fundamental shift. A variety of novel drugs and technologies have led to tremendous gains in the quality of care available for melanoma patients, particularly those with advanced stages of the disease. Here’s a look at some of the key advances that are driving progress in melanoma therapy today.
Immunotherapy is a relatively young field that has shown tremendous promise in treating patients with metastatic melanoma. It involves the use of specialized medicines to stimulate a patient’s own immune system to work harder or smarter to attack cancer cells. They are typically well tolerated with fewer side effects than conventional chemotherapies – but more importantly, many tumor responses have been long-lasting, extending patient survival by years, instead of months.
Since 2011, four new immunotherapies have been approved to treat melanoma, sometimes used in combination with one another, or with advanced radiation. Former President Jimmy Carter made headlines earlier this year when he announced he was cancer-free after his metastatic melanoma was treated with an immunotherapy drug called “pembrolizumab,” along with stereotactic radiosurgery, a noninvasive and highly precise radiation delivery method that uses fewer, high-dose treatments. Several other immunotherapies are currently in clinical development.
Melanoma tumors are typically classified as thin, medium or thick. Surgical removal is usually sufficient for thin tumors, but patients with medium tumors may have surgery and a sentinel lymph node biopsy, which is a test to see if the cancer has begun to spread. But recently, an added layer of sophistication – genetic profiling – has been added to the equation.
Doctors have identified some of the genetic mutations that drive cancer growth, and they can now conduct genetic profiling tests of a patient’s tumor to see if it contains any of the mutations linked to a higher risk of disease spread. This offers another important tool to help in the decision-making process about whether to pursue further treatment.
Genetic profiling of a patient’s tumor can also help guide which specific therapy should be used. Doctors have begun to develop drugs that are tailored to precisely target the mutations that drive cancer growth. When they work, such matches can have a dramatic effect on tumors. This approach to treatment – known as targeted therapy, or precision medicine – doesn’t usually lead to an outright cure, but rather helps doctors manage cancer like a chronic disease.
Targeted therapies differ from standard chemotherapies in several ways. As the name implies, targeted therapies act on specific molecular targets that are associated with cancer, whereas most standard chemotherapies act on all rapidly dividing normal and cancerous cells.
Surgical melanoma excision with the additional utilization of sentinel node evaluation for medium and thick tumors is standard. Mohs micrographic surgery, a specialized surgical technique, is used as an alternative to standard excision in certain melanoma cases, such as facial lesions. Mohs surgery involves the surgical removal of one thin layer of tissue at a time, and as each layer is removed, its margins are studied under a microscope for the presence of cancer cells.
This microscope-based technique is especially well suited for tumors located in highly sensitive areas. In one case at Scripps Clinic, a patient presented with a non-melanoma skin cancer tumor on his chest, located directly over his pacemaker. Only a few millimeters of fat separated the tumor from the pacemaker. The Mohs surgical technique allowed for the tumor to be removed, while preserving as much of the surrounding area as possible and not interfering with the function of pacemaker or causing any related complications.