Melanoma is a type of skin cancer that occurs in melanocytes, the cells that carry pigment.
But are there different types? How is it usually treated? And are there any new therapies available?
We checked in with melanoma specialist Isabella Glitza Oliva, M.D., Ph.D., for answers to these questions and more. Here’s what she had to say.
What are the different types of melanoma?
The vast majority of cases occur in the skin and are called cutaneous melanomas. These can be further subdivided into four major types. The most common one is superficial spreading, followed by nodular melanoma. Other cutaneous melanomas include lentigo maligna and acral lentiginous.
But melanomas can also develop in melanocytes located in other areas, including the eye (uveal and conjunctival melanomas) and mucosal surfaces throughout the body (mucosal melanoma), such as the gastrointestinal tract.
Desmoplastic melanoma is another distinct subtype that occurs in skin regions with chronic sun exposure. Other very rare subtypes include primary central nervous system melanoma, which occurs in the leptomeninges (the lining of the brain and spinal cord) and melanoma of soft parts (also known as clear cell sarcoma), which arises in the dermal layer of the skin and other soft tissues.
How is melanoma usually diagnosed?
Some melanomas are diagnosed during regular skin screenings. Others are found after patients notice a swollen lymph node in their neck, armpit, or groin. And in a few patients, melanoma is discovered entirely by chance, during a scan that was ordered for another medical reason.
But in a good number of cases, either the patient or somebody close to them notices a change in a pre-existing mole. That spurs them to see a dermatologist, who then orders a biopsy.
How is melanoma staged?
Staging for melanoma is usually based on the three-tiered “T-N-M” model.
All of these taken together are what doctors use to determine how advanced a particular melanoma is.
How is melanoma typically treated?
That all depends on the stage. Surgery is the initial treatment in most cases, especially if the cancer has not spread. Some patients may require radiation therapy, too. But melanoma can also be treated with a variety of other systemic therapies, such as targeted therapy and immunotherapy.
At MD Anderson, treatment is tailored to the specific needs of each patient. So, we take into consideration the type of melanoma, its stage and any other medical issues a patient might have.
What are the latest advances in melanoma diagnosis and treatment?
Over the past decade, the Food and Drug Administration (FDA) has approved a number new drugs for the treatment of melanoma.
In the immunotherapy category alone, there are ipilumumab, pembrolizumab, and nivolumab, plus the combination of ipilumumab and nivolumab taken together. These are given through an IV.
There are also three FDA-approved oral targeted therapy drug combinations for melanoma patients with a BRAF mutation: vemurafenib and cobimetinib, dabrafenib and trametinib, and encorafenib and binimetinib.
Other approaches for treating advanced melanoma include injecting an oncolytic virus called talimogene laherparepvec (T-VEC) directly into the tumor.
Not all of these therapies will work for everybody, of course, but it’s still really exciting to have them. Because now, patients have many great FDA-approved medications available, and numerous clinical trials they can join, should they exhaust all current treatment options.
We’re seeing some really amazing results, too. Patients who would’ve lived maybe 4 to 6 months after being diagnosed with a melanoma brain metastasis before, for example, have a chance of living for years. And some are seeing complete responses. So, while we still have a lot more work to do to help our patients, having melanoma today is very different from having melanoma a decade ago.