It is a frightening statistic—one in five of us will develop skin cancer by the time we turn 70, according to the Skin Cancer Foundation. That’s despite the fact that we all know the basics about protecting our skin by always wearing sunscreen and a hat…avoiding the sun when it is at its strongest…checking our skin regularly for anything that looks suspicious…and, of course, never using tanning beds.
Yet, skin cancer is the most common type of cancer in the US and around the globe. Even worse: The rates of the three major types of skin cancer—basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma—have been rapidly rising in recent decades. These alarming increases are attributed to several factors, including depletion of the ozone layer, which translates into greater and more potent UV exposure…increased longevity (skin cancer is more common in older adults)…more frequent travel to tropical destinations… and use of indoor tanning devices.
But there is good news: The likelihood of dying from skin cancer is declining, due to increased awareness about how to prevent the disease (sunscreen, sunscreen, sunscreen!) and early detection. Even better: There have been advances in treatments that are helping to squash this deadly disease.
WHAT IS SKIN CANCER?
Skin cancer occurs when abnormal cells grow rapidly in the outer layer (epidermis) of the skin as a result of damage to DNA and subsequent genetic mutations. This damage typically is caused by UV radiation from the sun.
BCCs and SCCs generally pose little risk for death, but melanoma can be deadly, especially if it’s not caught early. Reason: Melanomas tend to grow more rapidly and are much more likely to invade the bloodstream and lymphatics and spread to regional lymph nodes and ultimately distant organs. But: If caught and treated early, 99% of people with melanoma will still be alive in five years.
LIGHTER VS. DARKER SKIN
Lighter-skinned people with naturally blonde or red hair, light-colored eyes and freckles are most at risk for skin cancer because their skin contains relatively less pigment (melanin), which is protective against UV-induced damage. Lighter-skinned people tend to get skin cancer on body parts that are often exposed to the sun—both those more chronically exposed (face, chest and tops of the hands), as well as those areas subject to acute, intermittent “sunburst” exposure (the back and shoulders in men and the lower legs in women).
But that doesn’t mean that people with olive, brown or black skin can’t get melanoma and other skin cancers. In fact, the death rate from skin cancer is higher among darker-skinned people because awareness of the risk is low and because diagnosis and, ultimately, treatment may be delayed.
Recent finding: Skin cancers among darker-skinned people are less linked to sun exposure and demonstrate different genetic mutations than skin cancers in their fair-skinned counterparts. Melanomas in darker ethnicities are more commonly seen in sun-protected areas of the skin, such as the palms and soles (a specific subtype known as acral lentiginous melanoma), the mucosa (for example, inside the mouth and the genital region) and beneath the nail bed. These lesions often evade detection and are diagnosed at a later stage.
IMMUNOTHERAPY IS THE WORD
The immune system has a natural ability to attack tumors, but when our immune system’s ability to look for and correct DNA damage is impaired (due to UV-induced immunosuppresion, local or systemic infections, or unrelated malignancies), genetic mutations accumulate and skin cancers emerge.
For decades, surgery, chemotherapy and sometimes radiation therapy have been the staples of skin cancer treatment. These still are effective in many cases, but chemotherapy, in particular, can cause many debilitating side effects, including fatigue, rash, bruising, diarrhea and hair loss. Reason: Chemotherapy drugs target rapidly dividing cells—the hallmark of cancer—but they do so nonspecifically and so also damage healthy cells that divide rapidly such as those of the skin, gastrointestinal tract and hair follicles.
Enter immunotherapy with revolutionary drugs known as checkpoint inhibitors that specifically target cancerous cells. Immunotherapy revs up the body’s own immune system to attack tumors and acts on certain proteins and specific pathways (or checkpoints) that block the body’s ability to fight cancers. Research has shown this treatment can lead to long remissions and extend survival for people with advanced melanomas. Recent studies demonstrate that both alone and in combination, checkpoint inhibitors such as ipilimumab (Yervoy) and nivolumab (Opdivo) can suppress melanoma tumors that have spread to other organs, such as the brain, for years. Downside: These drugs don’t work for all melanomas and the drugs themselves may lead to skin, kidney and lung damage in addition to other side effects that may limit their efficacy.
Until the advent of immunotherapy, survival had typically been measured in only months for people with advanced melanomas. Eventually, these types of drugs and combinations may be able to cure melanomas completely even when they have spread to other organs.
Thousands of studies are being conducted worldwide using immunotherapy for advanced skin cancer as well as other cancers—and there are other types of immunotherapies beyond checkpoint inhibitors that are being studied. In the past, immunotherapy would be offered only after chemotherapy had failed, but today many oncologists believe it should be used as an initial treatment for advanced melanomas.
THERAPEUTIC VACCINES
We typically think of a vaccine as a way to prevent disease, but there are some vaccines being developed to treat tumors and prevent them from coming back after they’ve been surgically removed. The vaccines work by helping the immune system remember what to do if it detects melanoma cells in the future. Example: Pharmaceutical company Moderna recently announced that its experimental mRNA melanoma vaccine successfully reduced the risk for relapse or death from melanoma when it was combined with the checkpoint inhibitor pembrolizumab (Keytruda). The vaccine is customized for the patient to target a specific tumor and genetic mutation.
WILL IT SPREAD?
Unfortunately, even if a melanoma is completely removed or eradicated, it still can come back in the same or a different body part. Good news: Tests have been developed that can help doctors assess how likely a recurrence is. Example: Researchers at Newcastle University in the UK have developed the AMBLor test, which uses biopsied tissue of an early-stage melanoma to reliably predict if the melanoma is likely to recur, indicating that more frequent screenings and potentially adjuvant therapy are appropriate.
The ABCs of Melanomas
Keep an eye out for these signs…
Asymmetry: A mole looks different on one side versus the other.
Border irregularity: A mole has an irregular (not round) shape with jagged or indistinct borders.
Color variation: A mole has different colors within a single lesion.
Diameter or Dark: Lesions that are bigger than one-quarter of an inch (the size of a pencil eraser) and/or darker than other lesions on an individual warrant closer attention.
Evolving: A lesion that changes in color, size, shape, texture and/or symptoms (scabbing or bleeding) warrants prompt evaluation.
Darker-skinned people should look for the ABCDEs of melanoma as well as signs of acral lentiginous melanoma, signaled by…
Black or brown spots on the palms of the hands, soles of the feet or nail beds.
A spot that bleeds, doesn’t heal and/or grows bigger over time.