What’s New in Basal and Squamous Cell Skin Cancer Research?

Research into the causes, prevention, detection, and treatment of basal and squamous cell skin cancer is going on in many medical centers throughout the world.

Research into the causes, prevention, detection, and treatment of basal and squamous cell skin cancer is going on in many medical centers throughout the world.

Basic skin cancer research

Scientists have made a great deal of progress in recent years in learning how ultraviolet (UV) light damages the DNA (genes) inside normal skin cells, and how this might cause them to become cancer cells. Researchers are working to apply this new information to strategies for preventing and treating skin cancers.

Public education

Most skin cancers can be prevented. The best way to lower the number of skin cancers and the serious problems they can cause is to educate people about skin cancer risk factors and prevention. It’s important for health care professionals and skin cancer survivors to remind others about the dangers of too much UV exposure (both from the sun and from man-made sources such as tanning beds) and about the ways you can protect your skin from UV rays.

Skin cancer can often be found early, when it is most likely to be cured. Monthly skin self-exams and awareness of the warning signs of skin cancer may be helpful in finding most skin cancer when they are at an early, curable stage.

The American Academy of Dermatology (AAD) sponsors annual free skin cancer screenings throughout the country. Many local American Cancer Society offices work closely with AAD to provide volunteers for registration, coordination, and education efforts related to these free screenings. Look for information in your area about these screenings or contact the American Academy of Dermatology for more information.

Preventing genital skin cancers

Squamous cell cancers that start in the genital region account for a large proportion of the deaths from this type of skin cancer. Many of these cancers are related to infection with certain types of human papillomavirus (HPV), which can be spread through sexual contact. Limiting sexual partners and using safer sex practices such as wearing condoms may therefore help lower the risk of some of these cancers.

Vaccines are available to help protect against infection from some types of HPV that can cause certain cancers. These vaccines are recommended in certain age groups to help lower the risk of getting some types of cancer, and they may also lower the risk of some squamous cell skin cancers. To lean more, see HPV Vaccines.

Chemoprevention

Chemoprevention is the use of drugs to reduce cancer risk. This is likely to be more useful for people at high risk of skin cancers, such as those with certain congenital conditions (basal cell nevus syndrome (Gorlin syndrome), xeroderma pigmentosum, etc.), a history of skin cancer, or those with weakened immune systems (such as people who've had organ transplants), rather than for people at average risk of skin cancer.

Some of the most widely studied drugs so far are the retinoids, which are drugs related to vitamin A. They have shown some promise in reducing the risk of squamous cell cancers, but they can have side effects, including possibly causing birth defects. For this reason, they are not widely used at this time, except in some people at very high risk. Further studies of retinoids are under way.

Nicotinamide, a form of vitamin B3, has been shown to lower the risk of basal and squamous cell cancers in people at high risk, and with very few side effects, although it hasn’t been studied extensively in people with weakened immune systems.

Targeted drugs called hedgehog pathway inhibitors may help some people with basal cell nevus syndrome. For example, the drug vismodegib (Erivedge) has been shown to lower the number of new basal cell cancers and shrink existing tumors in people with this syndrome. The drug can have side effects, including taste loss and muscle cramps, which can make it hard for some people to take it every day. Further research on this and similar drugs is under way.

Other drugs are also being studied to reduce the risk of basal and squamous cell skin cancers in people at high risk.

Early detection, diagnosis, and testing

Smartphone apps

In recent years, many smartphone apps have been developed that claim to help identify skin cancers. Recent advances in artificial intelligence (AI) may help make these apps better at identifying concerning areas on the skin that need to be looked at by a doctor.

While these tools may eventually prove to be helpful, it’s not yet clear how accurate they are, and more research is needed before expert groups would recommend them. For now, it’s best to have any area you’re concerned about looked at by a trained health professional.

Spectroscopic devices to help diagnose skin tumors

Some newer handheld devices might help health care providers get a better idea if an abnormal area on the skin is likely to be cancer, without needing to remove it. These types of devices might be especially helpful for primary care providers and other health professionals who don’t usually see as many skin cancers as dermatologists do.

Once the device is placed over the skin, the tip of the device sends out light particles or electrical signals, which then bounce off the skin cells and are detected by the device. The patterns of signals from cancer cells tend to be different from those of normal cells. The device can analyze the pattern coming from the area and let the provider know if it’s likely to be cancer (and therefore needs further testing).

Optical biopsies

Some newer approaches to diagnosing skin cancer don’t require the removal of a skin sample. For example, in reflectance confocal microscopy (RCM), a low-powered laser is aimed at the suspicious area. The light from the laser enters the upper layers of the skin and reflects off the structures there. A special microscope detects the light as it bounces back, which is used to create a detailed, three-dimensional image of the area. This can help the doctor determine if the area needs to be removed. RCM is now available in some centers and will likely become more common in the coming years.

Testing for biomarkers

While it’s not common for basal or squamous cell cancers to spread to other parts of the body, these cancers can be hard to treat once they do. Doctors are now looking for better ways to determine which skin cancers (especially squamous cell cancers) are likely to grow and spread more quickly, and therefore might require more intense treatment.

One way to do this is to test the cancer cells for certain biomarkers, which are gene or protein changes inside the cells that can help tell if a cancer is more likely to grow and spread. Some research is looking at the activity of many genes at once (known as gene expression profiling) to see if these patterns can help predict risk. Other studies are looking at single biomarkers. For example, some research has shown that squamous cell skin cancers seem to be more likely to spread if the cells have higher levels of the PD-L1 protein, or lower levels of the INPP5A protein.

More research is needed before testing tumors for biomarkers becomes commonly used.

Treatment

Local treatments

Current local treatments such as surgery and radiation therapy work well for most basal and squamous cell skin cancers. Still, even some small cancers can be hard to treat if they’re in certain areas. Newer forms of non-surgical treatment such as new topical drugs (drugs applied to the skin), photodynamic therapy, and laser surgery may help reduce scarring and other possible side effects of treatment.

Treating advanced disease

Most basal and squamous cell skin cancers are found and treated at an early stage, when they are likely to be cured, but some can grow into other areas or spread to other parts of the body. These cancers can often be hard to treat with therapies such as radiation and chemotherapy.

Squamous cell cancers: Several studies are testing newer targeted drugs for advanced squamous cell cancers. For example, cells from these cancers often have too much of the EGFR protein on their surfaces, which can help them grow. Drugs that target this protein, such cetuximab (Erbitux), are now being tested in clinical trials, both alone and combined with other treatments.

Immunotherapy is another newer approach to treating some advanced squamous cell cancers. Drugs called immune checkpoint inhibitors are now coming into use as an option to treat some of these cancers.

Basal cell cancers: It’s very rare for basal cell cancers to reach an advanced stage, but when they do, these cancers can be hard to treat. Vismodegib and sonidegib, drugs that target the hedgehog signaling pathway in cells, may help some people (see Targeted Therapy for Basal and Squamous Cell Skin Cancers). Other drugs that target this pathway are now being studied as well.

Immunotherapy drugs called immune checkpoint inhibitors are now an option to treat some of these cancers as well.