1223 GMT December 15, 2018
Researchers found the heightened risk among patients who'd had many bouts of basal cell carcinoma (BCC) — a highly treatable form of skin cancer diagnosed in over three million Americans each year, HealthDay News wrote.
Patients who'd developed at least six BCCs over 10 years showed higher-than-average risks of breast, colon, prostate and blood cancers.
It's well known that people who develop any form of skin cancer face an increased risk of other skin cancers — including the most serious form, melanoma.
"This study shows that when people have frequent basal cell carcinomas, they also have an increased risk of internal cancers — which hasn't been seen before," said lead researcher Dr. Kavita Sarin.
Basal cell carcinoma, which is caused mainly by ultraviolet (UV) exposure, is highly curable. And the vast majority of people do not develop it at the frequency linked to internal cancers, according to Sarin, an assistant professor of dermatology at Stanford University.
She said her team's findings suggest that when people do have such frequent recurrences, it may signal an underlying susceptibility to cancer more generally.
For the study, the researchers analyzed the DNA of 61 patients with frequent basal cell carcinomas, and found 20 percent had mutations in genes that help repair DNA damage in body cells. Cancer arises when such abnormal cells grow and spread unchecked.
"That 20 percent figure is much higher than you'd see in the general population," Sarin said.
She cautioned, though, that the finding is based on a small group of patients, and further research is necessary.
Dr. Vernon Sondak, who heads the skin cancer department at Moffitt Cancer Center, in Tampa, Fla., called the findings important, though not surprising.
It has long been thought that the skin can serve as a ‘tip off’ that a person is relatively more vulnerable to DNA damage from various exposures.
"This suggests that the same underlying biology that makes some people especially vulnerable to DNA damage from UV radiation may also make them more susceptible to other cancers," said Sondak, who was not involved in the study.
People who have a history of frequent BCCs should be sure to get the recommended screenings for other cancers, like breast and colon cancers, Sondak said.