Internal medicine has released a new study that found no difference in the risk of breast cancer between women who were vaccinated against the HPV-16-preventable strain of the virus and those who were not.
The study was released Wednesday by the American Cancer Society.
The study’s findings were based on data from more than 6,000 women enrolled in the National Breast Cancer Surveillance Program.
“There was no difference between the vaccinated and unvaccinated women in terms of breast tumor incidence or survival,” said Dr. Daniel Kannam, MD, PhD, associate professor of internal medicine at the University of California, San Francisco.
“Women who received the vaccine showed a decrease in the odds of developing a first-degree relative breast cancer in the follow-up period,” Dr. Kannac said.
“We know that the HPV16 vaccine protects against cancer, but it does not necessarily protect against breast cancer,” he said.
The study is the first to show a statistically significant difference in breast cancer rates among vaccinated and not vaccinated women.
In contrast, other studies have shown a significant association between the HPV vaccine and an increased risk of ovarian cancer.
Dr. Kamp said the study is also the first that looked at the effects of the HPV vaccines on the immune system.
“The results of this study were not consistent across the study population,” he wrote in the report.
“The results may indicate that the immune response to the vaccine may be stronger in vaccinated individuals and less strong in unvaccined individuals, but this study does not have sufficient power to determine the cause-and-effect relationship between immune response and cancer incidence and survival.”
Dr. Srinivasan, a spokesperson for the American Academy of Family Physicians, said the association between vaccine and cancer is an emerging issue.
“While the study’s results are encouraging, we also know that vaccines can be very effective in preventing cancer,” Dr Srinasan said in a statement.
“It is important to remember that the vaccines are not 100 percent effective, and there are many other factors that influence the effectiveness of a vaccine.”
The vaccine is a combination of three strains of the human papillomavirus, the vaccine is approved for use in the U.S. and other countries.
The HPV-6 vaccine has been shown to be safe and effective in reducing the risk for cervical cancer, and the HPV 16 vaccine has shown to have the most significant benefits in preventing ovarian cancer, according to the U,S.
Department of Health and Human Services.
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