Viral Differences in Cervical Cancer

Cervical cancer HPV viruses differed between white and black women

(RxWiki News) Most, if not all, cervical cancers are caused by the human papillomavirus (HPV). There are 40 different types of this virus. HPV types linked to cervical cancer may be different in women of different races.

A new study discovered that the HPV types that caused cervical cancer in black women were different than the HPV types that caused the disease in white women.

HPV vaccines currently available do not protect against the virus types most commonly seen in black women.

"Discuss HPV vaccination with your physician."

This study was conducted by Cathrine Hoyo, PhD, MPH, associate professor in the Obstetrics and Gynecology Department at Duke University School of Medicine in Durham, NC, and colleagues.

HPV is a sexually transmitted virus that is known to cause cervical cancer. The virus is also linked to oral, anal and other gynecologic cancers.

Cervical cancer starts with cell changes called cervical intraepithelial neoplasia (CIN) that can progress to full-blown cancer.

Persistent infection with HPV — most commonly HPV 16 and 18 — leads to cervical cancer.

Current HPV vaccines — Cervarix and Gardasil — are designed to protect against the HPV 16 and 18 subtypes.

According to Dr. Hoyo, black women are 20 percent more likely to develop cervical cancer and twice as likely to die from the disease than white women.

Dr. Hoyo and colleagues are enrolling women who are having an examination called a colposcopy following an abnormal Pap test into the Cervical Intraepithelial Neoplasia Cohort Study (CINCS) to better understand these disparities.

The study's aim is to identify markers that distinguish early CIN (CIN1) from more advanced lesions (CIN2 and 3).

The HPV subtypes present in CIN have already been analyzed in 572 women, including 280 black and 292 white women.

The most common HPV subtypes found in CIN1 in white women were HPV 16, 18, 31, 56, 39 and 66, while HPV 33, 35, 58 and 68 were seen most frequently in black women with CIN1.

When looking at more advanced lesions (CIN2 and CIN3), the researchers found that white women most often had HPV subtypes 16, 18, 33, 39 and 59, while the black women most frequently had HPV 31, 35, 45, 56, 58, 66 and 68.

A vaccine that targets some but not all of the HPV subtypes seen frequently in black women is currently being tested in phase lll trials.

The vaccine under development is designed to protect against HPV subtypes 6, 11, 16, 18, 31, 33, 45, 52 and 58.

If and when it’s approved, this vaccine may be more beneficial for black women, Dr. Hoyo suggested.

“However, the vaccine does not include HPV 35, 66, and 68,” she added. “We need more African-American women to enroll in trials like this to see how beneficial this new vaccine will be for them,” Dr. Hoyo concluded.

The authors stated that these findings need to be replicated in larger studies.

Results from this study were presented at the 12th Annual American Association for Cancer Research (AACR) International Conference on Frontiers in Cancer Prevention Research.

All research is considered preliminary before publication in a peer-reviewed journal.

This study was funded by the National Institutes of Health and National Cancer Institute. Dr. Hoyo declared no conflicts of interest.

Review Date: 
October 25, 2013