Wednesday June 25, 2014 (foodconsumer.org) -- A new study provides new evidence to suggest that infection of human papillomavirus (HPV) may increase the risk of breast cancer.

Previous studies have already hinted that HPV infection may have something to do with breast cancer pathogenesis.  The current study conducted in Iraq shows that various genotypes of HPV may be present in the breast tissue from patients diagnosed with malignant breast cancer.   In comparison, patients who were diagnosed with benign tumors and healthy women are much less likely to have HPV in their breast tissue.

Specifically, among 129 patients diagnosed with breast cancer, mixed HPV genotypes were found in 46.5% of their tissue samples.  Of HPV types,  genotypes 16, 18, 31 and 33 were found in 55.5%, 58.4%, 65% and 26.6% of the patients, respectively.

To be exact, "Mixed HPV genotypes 16 + 18, 16 + 18 + 31, 16 + 18 + 33, 18 + 33, 16 + 31 and 18 + 31 were found in 5.0%, 25.0%, 8.3%, 7.7%, 10.0% and 13.3% of cancer cases respectively," the study found.

Among 24 patients diagnosed with benign breast tumors, only three patients were found to have HPV in their breast tissue and among 20 healthy women, no one was found to have any HPV in their breast tissue.

The study concluded "The detection of high-oncogenic HPV genotypes in patients with breast cancer supports the hypothesis of an etiologic role for the virus in breast cancer development."

Human papillomavirus, a sexually transmitted disease, has been already known to increase risk of cervical cancer.  The HPV infection is so common that nearly half the men and women in the U.S. is expected to contract the virus in their lifetime. But because cervical cancer is relatively rare, this HPV infection is not considered a major risk for women's health. 

Ali SH, Al-Alwan NA, Al-Alwany SH.  Detection and genotyping of human papillomavirus in breast cancer tissues from Iraqi patients.  East Mediterr Health J. 2014 Jun 18;20(6):372-377.