Several studies presented at the 2010 International AIDS Conference in Vienna, Austria, examined factors that increase risk for development of pre-cervical cancer and cervical cancer in HIV-positive women, as well as factors involved in recurrence of pre-cervical cancer.

Pre-cervical cancer (cervical intraepithelial neoplasia) is characterized by the appearance of abnormal cells on the surface of the cervix. Typically, most cases are relatively stable and can be eliminated by the body’s immune system.

However, a small percentage of cases develop into cervical cancer.

Previous research has shown that HIV-positive women are around four times more likely to develop genital lesions and cervical cancer, with 20 percent to 60 percent of HIV-positive women showing signs of pre-cervical cancer.

One of the major causes of pre-cervical cancer is the sexually transmitted human papillomavirus (HPV). Around 75 percent to 80 percent of women with HIV also have HPV. Women with HIV have a weakened immune system, which allows HPV to survive in the cervix and cause pre-cancerous lesions.

In the studies presented at AIDS 2010, researchers sought to further understand pre-cervical cancer and cervical cancer in HIV-positive women. In general, the studies found that having lower CD4 (white blood cell) counts and a weakened immune system are risk factors for pre-cervical cancer and cervical cancer.

Additionally, women with HIV are more likely to have a recurrence of pre-cervical cancer and tend to have more abnormal cells in both the cervix and the anus. Antiretroviral therapy was not found to protect HIV-positive women from development of pre-cervical cancer.

Anal And Cervical Cellular Abnormalities In HIV-Infected Women

An ongoing study presented at the conference examined rates of anal and cervical abnormalities in HIV-infected women.

Results from 88 women were examined. Most of the women (82 percent) were on antiretroviral therapy and 56 percent of the women had an undetectable HIV viral load (amount of virus in the blood).

Results showed that 81 percent of the women tested positive for HPV in the anus and 68 percent in the cervix.

Additionally, 44 percent of the women had abnormal cells in the anus and/or the cervix (anus: 26 percent, cervix: 28 percent), with 10 percent showing abnormal cells in both regions.

The researchers concluded that there is a high rate of HPV infection and abnormalities in the anus and/or cervix for HIV-infected women.

Risk Factors For Pre-Cervical Cancer In HIV-Positive Women

Another study examined the risk factors for pre-cervical cancer in women with HIV. The researchers found that the primary risk factor is a history of immunosuppression, signs of which include decreased CD4 cell counts and the presence of HPV DNA on the cervix.

The study was conducted from 1998 to 2008 and enrolled 523 HIV-positive women from five cities in Brazil. All women underwent gynecologic exams, and samples from their cervix were collected, including HPV DNA and a Pap smear.

Researchers found that 22 percent of the women had pre-cervical cancer, with 6 percent characterized as severe and 16 percent as mild. Women with low CD4 cell counts (below 200 cells per microliter) had an increased risk of developing pre-cervical cancer.

Additionally, researchers found that women with DNA from certain high-risk strains of HPV were more likely to have pre-cervical cancer. These strains are known to be associated with cervical cancer.

The scientists found that antiretroviral therapy had no protective effect against pre-cervical cancer.

Pre-Cervical Cancer In Untreated HIV-Infected Women

This study sought to determine risk factors for pre-cervical cancer development in HIV-infected women who were not on antiretroviral therapy. Researchers found that multiple sexual partners and the presence of certain other sexually transmitted infections were associated with higher risk for pre-cervical cancer.

The two-year study enrolled 246 HIV-infected women who were not receiving antiretroviral therapy.

Both pelvic examinations and Pap smear evaluations were conducted every six months in order to observe development of pre-cervical cancer. Additionally, tests were conducted to diagnose sexually transmitted infections and HPV.

Results showed that common factors associated with the development of pre-cervical cancer included having multiple sexual partners (more than three within the past year), HPV, trichomoniasis (a sexually transmitted infection), genital herpes, and syphilis.

Women who developed pre-cervical cancer also had lower CD4 counts and higher viral loads than women who did not.

Pre-Cervical Cancer Recurrence In HIV-Infected And Non-Infected Women

Another study sought to identify risk factors associated with the recurrence of pre-cervical cancer in women with or without HIV. Researchers found that glandular involvement, where abnormal cells are found inside the cervix and not just on the outer surface, and being HIV positive both increased the risk of pre-cervical cancer recurrence.

This study examined pre-cervical cancer recurrence after a procedure called loop electrosurgical excision, a minor surgery that removes lesions while still preserving cervix anatomy and function.

Women with pre-cervical cancers are at risk for recurrence, so follow-up after a surgical procedure is essential.

This study enrolled 33 patients with and 105 patients without recurrent pre-cervical cancer. Cervical samples were collected at the beginning and at the end of the study period.

Results showed that in 58 percent of patients with pre-cervical cancer recurrence, there was a positive test for HPV DNA. Additionally, glandular involvement and being HIV positive were both risk factors associated with the recurrence of pre-cervical cancer.

Cervical Cancer In HIV-Infected Women On Antiretroviral Therapy

This study examined risk factors for progression to cervical cancer in women with HIV. Results showed that women who went on to develop cervical cancer after beginning antiretroviral therapy had lower average CD4 counts, both before and after initiation of antiretroviral therapy, than women who did not develop cancer.

The researchers looked at HIV-infected women who were diagnosed with cervical cancer and found that before their cancer and before starting antiretroviral therapy, the women had lower CD4 cell counts than HIV-positive women who did not develop cervical cancer.

Results also showed that women who eventually developed cervical cancer did not respond as well to antiretroviral therapy. The scientists tracked women who started with the same CD4 cell counts when they began antiretroviral therapy. They found that women who later developed cervical cancer had lower CD4 counts a year after starting therapy than women who did not develop cancer.

The researchers suggested a poor immune status and a poor response to antiretroviral therapy may be associated with a higher risk of developing cervical cancer in HIV-positive women.

For more information, please see the AIDS 2010 conference website.