Twin ports doctors warn of an “unprehistoric increase” in skin cancer cases in the United States.
The World Health Organization reported last month that skin cancers in the U.S. increased nearly 10 percent last year and the number of new cases rose by nearly 40 percent from 2015 to 2016.
The report, published Tuesday in the journal JAMA Dermatology, said twin ports are among the highest-risk areas for skin cancers.
The study analyzed more than 30,000 new skin cancers and found that about 10 percent of the newly diagnosed skin cancers had no known causes.
The twin port dermatologist said twin port patients who were hospitalized for complications during the study had a “high risk” of developing a skin cancer in the future.
The doctors said twin-port patients who had received a bone marrow transplant had a lower risk of skin cancer, but had more of a risk for bone marrow cancer, a type of skin tumor that develops after the bone marrow separates from the bone and divides into multiple cells.
“The increased incidence of skin cancers among twin port people may reflect an increase in the number and types of skin lesions they had as a result of their transplanted bone marrow, which may have resulted in an increased risk of subsequent skin cancer,” the doctors wrote.
Dr. Peter D. Lappe, a twin port doctor who co-authored the report, said the increase in cases could be due to twin port transplants.
Doctors have said that twin-ports can cause more skin cancers than other types of transplant.
Lappe said that if the increased skin cancer rates in twin port centers were due to the transplants themselves, it would be similar to the increased rates of cancer among people with melanoma, which is a skin tumor.
There are more than 3,500 twin ports in the US, and the twin ports have been in use since the 1950s.
More than 40 percent of all twin port-related skin cancers occur in the upper and lower limbs, according to the study.
About 3,000 twin port clinics operate in the country, and about 60 percent of those clinics have been approved to treat patients with bone marrow transplants, according the researchers.
Some experts have suggested that the increased rate of twin port cases could reflect the increased number of twin-ported patients, and could also be a result from the higher number of twins in the population, because twin port families tend to be older and healthier.
A study released in May by the CDC found that twin port babies and their mothers are at a higher risk for skin cancer than other children.
CDC data showed that twin ports were found to be at the highest risk for developing melanoma and leukemia.