And if they have a strong family history of any of those internal cancers, he noted, they might talk to their doctors about whether screening at an earlier age is a good idea.
Sarin agreed, and said that in some cases, genetic testing might be suggested.
The study findings are based on the 61 patients at Stanford who’d been treated for an unusually large number of BCCs — an average of 11 times over 10 years. More than one-third of them had a history of other cancers, too.
Among patients with at least six basal cell carcinoma diagnoses, the risks of blood, breast, colon and prostate cancers were roughly three- to six-times higher, versus the norm for Americans of the same age and race, the study authors reported.
The researchers then confirmed the pattern using a health insurance database with information on over 111,000 BCC patients. Again, people with frequent basal cell carcinomas had increased risks of internal cancers, including blood and colon cancers.
Among the Stanford patients, 20 percent had mutations in any of a dozen genes involved in DNA repair — including the BRCA genes linked to breast and ovarian cancers.
In contrast, that would be seen in about 3 percent of the general population, according to Sarin.