Cancer-fighting cocktail demonstrates promising results as treatment for advanced cervical cancer
Combining a standard chemotherapy drug with a second drug that stops cells from dividing improves both the survival and response rates for those with advanced cervical cancer, a new study by UT Southwestern Medical Center cancer researchers finds.
The cancer-fighting cocktail, which combines the chemotherapy drug cisplatin with pemetrexed - an agent that stops cancer cells from dividing - showed promising results for advanced, persistent, or recurrent cervical cancer.
"We found that pemetrexed combined with cisplatin is less toxic, well tolerated, and should be developed for further treatment of cervical cancer," said gynecologic oncology specialist Dr. David Miller, Professor of Obstetrics and Gynecology and a member of the Harold C. Simmons Cancer Center.
In the Phase II clinical trial, Dr. Miller and colleagues in the National Cancer Institute –supported Gynecologic Oncology Group found that in patients who had not received prior chemotherapy, the combination cocktail had a 31 percent response rate for up to 7 months, and an overall survival of 12 months. This outcome compares to the standard alternative—the combination of cisplatin with the chemotherapy drug paclitaxel, which showed a response rate against the tumor of 29 percent for up to 6 months and an overall survival of 13 months.
While comparable in efficacy, Dr. Miller noted that the pemetrexed combination was less toxic to patients than the paclitaxel combination, and could therefore be a better therapeutic option.
Adding a third drug, called bevacizumab, to the cisplatin-plus-paclitaxel cocktail further increased patient survival and is now the standard of care for patients with metastatic or recurrent carcinoma of the cervix. So the researchers suggested that combining bevacizumab with cisplatin and pemetrexed may offer further survival benefits as well.
"Given that pemetrexed combined with cisplatin may be less toxic than and as active as cisplatin plus paclitaxel and that it can be combined with bevacizumab, investigating the comparison of cisplatin-pemetrexed plus bevacizumab with cisplatin-paclitaxel plus bevacizumab would be the next appropriate step," said Dr. Miller, who holds the Amy and Vernon E. Faulconer Distinguished Chair in Medical Science and the Dallas Foundation Chair in Gynecologic Oncology.
The findings, published online in the Journal of Clinical Oncology, are important because patients with metastatic or recurring tumors face a poor prognosis, and no curative therapy currently exists.
More than 12,000 women in the United States were diagnosed with cervical cancer in 2011, the most recent figures available from the Centers for Disease Control, with nearly 4,100 related deaths. However, a 2014 study in JAMA suggests the rates may be far higher – about 18.6 cases per 100,000 women rather than 12 per 100,000 previously thought. That study also suggested the risk for cervical cancer grew as women age, and was more prevalent among African-American women.
Cervical cancer used to be the leading cause of cancer death for women in the U.S., according to the CDC, but cases and deaths have declined over the years as more women have received regular Pap tests. Pap tests can identify cervical precancer before it turns into cancer. Another factor is use of the human papillomavirus (HPV) vaccine, because HPV is a root cause of most cervical cancers.