NCI-supported research at ASCO highlights advances in cervical cancer screening and treatment
Three NCI-supported trials were highlighted at the ASCO Annual Meeting in Chicago on June 2, 2013. The first trial, examining screening for cervical cancer, demonstrated that visual inspection with acetic acid reduced cervical cancer mortality. The technique used, VIA, relies on direct visualization of the cervix after it is swabbed with vinegar. The trial was conducted in India by local health workers and community residents who were trained to provide VIA to women who needed screening. More than 75,000 women from 10 communities had multiple rounds of VIA. The screened women were compared to over 76,000 women from 10 similar communities where women were informed about cancer risks and the available screening facilities, were given vouchers for free cervical cancer screening at a nearby hospital, but were not offered the outreach system with VIA performed by community health workers. The findings from this study showed that the community screening group had a 31 percent reduction in death due to cervical cancer, which is significant. The success of this trial in reducing death can be attributed to the combination of the VIA test and the outreach system that was developed.
The second trial, looking at treatment for cervical cancer, enrolled people with advanced, recurrent, or persistent cervical cancer that was not curable with standard therapy. The patients who had the drug bevacizumab (Avastin) added to their therapy lived 3.7 months longer than patients who did not receive the drug. Bevacizumab blocks the blood supply that feeds a tumor by binding to and inhibiting a growth factor that plays a critical role in tumor blood vessel growth. The clinical trial, GOG240, was sponsored by NCI and conducted by a network of researchers led by the Gynecologic Oncology Group (GOG). In another measure of trial success, progression free survival—meaning that after treatment the disease did not worsen—was 8.2 months for the women who received bevacizumab versus 5.9 months for those who received chemotherapy alone.
The third trial incorporated bevacizumab, but this time for the treatment of an aggressive brain tumor known as glioblastoma, in newly diagnosed patients. The clinical trial, RTOG 0825, was sponsored by NCI and conducted by a network of researchers led by the Radiation Therapy Oncology Group (RTOG), and enrolled 637 patients. The primary objective of the trial was to determine whether the addition of bevacizumab to temozolomide and radiation improved progression-free and/or overall survival. Temozolmide is toxic to cancer cells and acts by inhibiting DNA replication. The drug is given orally and penetrates well into the central nervous system. The results of the trial showed no overall survival benefit for patients who received bevacizumab compared to patients who did not receive the drug (15.7 months vs. 16.1 months, respectively). Patients who received bevacizumab also experienced more side effects compared to those treated with chemoradiation alone.