Common skin cancer can signal increased risk of other cancers, researchers say

August 9, 2018, Stanford University Medical Center
skin
Human skin structure. Credit: Wikipedia

People who develop abnormally frequent cases of a skin cancer known as basal cell carcinoma appear to be at significantly increased risk for the development of other cancers, including blood, breast, colon and prostate cancers, according to a preliminary study by researchers at the Stanford University School of Medicine.

The increased susceptibility is likely caused by mutations in a panel of proteins responsible for repairing DNA damage, the researchers found.

"We discovered that people who develop six or more basal cell carcinomas during a 10-year period are about three times more likely than the general population to develop other, unrelated cancers," said Kavita Sarin, MD, Ph.D., assistant professor of dermatology. "We're hopeful that this finding could be a way to identify people at an increased risk for a life-threatening malignancy before those cancers develop."

Sarin is the senior author of the study, which will be published online Aug. 9 in JCI Insight. Medical student Hyunje Cho is the lead author.

Largest organ

The skin is the largest organ of the body and the most vulnerable to DNA damage caused by the sun's ultraviolet rays. Try as one might, it's just not possible to completely avoid sun exposure, which is why proteins that repair DNA damage are important to prevent skin cancers like basal cell carcinoma.

Most of the time this system works well. But sometimes the repair team can't keep up. Basal cell carcinomas are common—more than 3 million cases a year are diagnosed in the United States alone—and usually highly treatable.

Sarin and Cho wondered whether the skin could serve as a kind of canary in the coal mine to reveal an individual's overall cancer susceptibility. "The skin is basically a walking mutagenesis experiment," Sarin said. "It's the best organ to detect genetic problems that could lead to cancers."

Sarin and Cho studied 61 people treated at Stanford Health Care for unusually frequent basal cell carcinomas—an average of 11 per patient over a 10-year period. They investigated whether these people may have mutations in 29 genes that code for DNA-damage-repair proteins.

"We found that about 20 percent of the people with frequent basal cell carcinomas have a mutation in one of the genes responsible for repairing DNA damage, versus about 3 percent of the general population. That's shockingly high," Sarin said.

Furthermore, 21 of the 61 people reported a history of additional cancers, including blood cancer, melanoma, prostate cancer, breast cancer and colon cancer—a prevalence that suggests the frequent basal cell patients are three times more likely than the general population to develop cancers.

'A strong correlation'

To confirm the findings, the researchers applied a similar analysis to a large medical insurance claims database. Over 13,000 people in the database had six or more basal cell carcinomas; these people also were over three times more likely to have developed other cancers, including colon, melanoma and blood cancers. Finally, the researchers identified an upward trend: the more basal cell carcinomas an individual reported, the more likely that person was to have had other cancers as well.

"I was surprised to see such a strong correlation," Sarin said. "But it's also very gratifying. Now we can ask patients with repeated basal cell carcinomas whether they have family members with other types of cancers, and perhaps suggest that they consider genetic testing and increased screening."

The researchers are continuing to enroll Stanford patients in the study, which is ongoing, to learn whether particular mutations in genes responsible for repairing DNA damage are linked to the development of specific malignancies. They'd also like to conduct a similar study in patients with frequent melanomas. But they emphasized that there's no reason for people with occasional basal cell carcinomas to worry.

"About 1 in 3 Caucasians will develop at some point in their lifetime," Sarin said. "That doesn't mean that you have an increased risk of other cancers. If, however, you've been diagnosed with several basal cell carcinomas within a few years, you may want to speak with your doctor about whether you should undergo increased or more intensive screening."

Explore further: Skin cancers linked with reduced risk of Alzheimer's disease

Related Stories

Skin cancers linked with reduced risk of Alzheimer's disease

April 19, 2018
Previous studies have demonstrated a decreased risk of Alzheimer's disease (AD) in individuals with various cancers, including non-melanoma skin cancers (including squamous cell cancers and basal cell cancers). A new Journal ...

Study reveals two-fold higher incidence of non-melanoma skin cancers for HIV patients

January 29, 2013
HIV-positive patients have a higher incidence of non-melanoma skin cancers, according to a Kaiser Permanente study that appears in the current online issue of the Journal of the National Cancer Institute. Specifically, basal ...

Skin cancer on the rise

May 15, 2017
New diagnoses for two types of skin cancer increased in recent years, according to a Mayo Clinic-led team of researchers.

Researchers study how patterns, timing of sunlight exposure contribute to skin cancers

October 23, 2012
(Medical Xpress)—Researchers at Moffitt Cancer Center, the University of South Florida and the International Agency for Research on Cancer in France have studied the patterns and timing of sunlight exposure and how each ...

Recommended for you

Scientists discover new method of diagnosing cancer with malaria protein

August 17, 2018
In a spectacular new study, researchers from the University of Copenhagen have discovered a method of diagnosing a broad range of cancers at their early stages by utilising a particular malaria protein that sticks to cancer ...

Researchers find pathways that uncover insight into development of lung cancer

August 17, 2018
Lung cancer is the leading cause of preventable cancer death. A disease of complex origin, lung cancer is usually considered to result from effects of smoking and from multiple genetic variants. One of these genetic components, ...

Developing an on-off switch for breast cancer treatment

August 17, 2018
T-cells play an important role in the body's immune system, and one of their tasks is to find and destroy infection. However, T-cells struggle to identify solid, cancerous tumors in the body. A current cancer therapy is using ...

Pregnant? Eating broccoli sprouts may reduce child's chances of breast cancer later in life

August 16, 2018
Researchers at the University of Alabama at Birmingham have found that a plant-based diet is more effective in preventing breast cancer later in life for the child if the mother consumed broccoli while pregnant. The 2018 ...

Scientists discover chemical which can kill glioblastoma cells

August 15, 2018
Aggressive brain tumour cells taken from patients self-destructed after being exposed to a chemical in laboratory tests, researchers have shown.

Three scientists share $500,000 prize for work on cancer therapy

August 15, 2018
Tumors once considered untreatable have disappeared and people previously given months to live are surviving for decades thanks to new therapies emerging from the work of three scientists chosen to receive a $500,000 medical ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.