Combined therapies show promise in treating prostate cancer
New methods for treating solid cancers can soon be offered to patients around the world.
The New England Journal of Medicine recently published a study examining how effective a multi-targeted therapy was in treating advanced prostate cancer, said Robert DiPaola, director of the Cancer Institute of New Jersey.
Multiple therapies were used to treat prostate cancer in a study going back 10 years.
“What was found when it was reported last year and published last month is that for prostate cancer (combining multiple therapies) has the largest survival benefit ever seen for chemotherapy,” he said.
Prostate cancer may present itself through changes in how one urinates or with erectile function problems, said Michael Carducci, a professor of Oncology and Urology at the Johns Hopkins Medical Institutions in an email.
Normally this form of cancer has no symptoms, said Carducci, one author of the study. Advanced forms of the cancers, meaning cancer that has spread to other parts of the body, can cause swelling, fatigue and bone pain.
This disease is typically treated by removing the cancerous tissue, he said. Surgical removal or different types of radiation treatment are used to treat the prostate.
“Advanced prostate cancer — recurrent and metastatic — is treated with agents that lower a man’s testosterone levels or surgical removal of the testicles,” Carducci said. “These agents or approaches are good at reducing the burden, but over time cancer cells ... survive without testosterone (and) repopulate.”
The purpose of the study was to determine what effect combined therapies had on the patient, said DiPaola, who is also the senior author of the paper. Recurrent prostate cancer is traditionally treated with a single method, androgen deprivation therapy (ADT).
ADT is a hormonal treatment, he said. It reduces testosterone levels in the body, which normally affects the cancer.
Combining this with chemotherapy was first proposed 10 years ago, DiPaola said. At the time, he chaired the Eastern Oncology Cooperative Group hosted by the National Cancer Institute. The group’s goal was to combine resources between different institutions to perform a national study.
“The trial was launched out of the committee I chaired,” he said. “It was launched nationally and patients enrolled (from the various) institutions (involved).”
Over the last decade, 790 patients were randomly split into two groups, DiPaola said. One group received the traditional hormone therapy, while the other experienced the experimental treatment.
Although the combined therapy was relatively new, the individual components, chemotherapy and hormone therapy, were both existing practices, he said.
The chemotherapy, performed with docetaxel, a drug already used to treat prostate cancer, began a few months after the hormone therapy, Carducci said.
Patients in the experimental trial lived an average of more than 16 months compared to the patients receiving the traditional therapy, he said.
Christopher Sweeney, an associate professor of medicine at the Dana-Farber Cancer Institute, said the results were initially presented more than a year ago to the American Society of Clinical Oncology and would have a significant impact on future therapies.
The reviewed study is published in the New England Journal of Medicine and can be used by doctors immediately when they discuss therapies with their patients, DiPaola said. The results of the study support using multi-targeted therapies earlier in a patient’s treatment.
The results also support using multiple therapies with other forms of cancer, he said. Some studies are already being performed with different types of cancer to verify this.
“Moving chemotherapy earlier in the course of disease has shown benefit in breast, colon and lung (cancers),” Carducci said.
DiPaola said the results of the prostate cancer trial can be applied to patients immediately.
“The publication (of the study) is the final piece required for treatment guidelines to be updated around the globe,” Sweeney said.
A follow-up study called STAMPEDE performed in the United Kingdom showed similar success, Carducci said. In STAMPEDE, patients lived about 10 months longer.
Multi-targeted therapies coincide with the CINJ’s Precision Medicine Initiative, DiPaola said. Each patient is unique, and the same treatment may not have the same effect on different people.
“If we can do a genomic assessment (of the patient’s cancer), we can approach with more multi-targeted therapies,” he said.
“What I hope and what I’m doing next is developing this whole new paradigm in using multi-targeted approaches earlier in treatments,” DiPaola said.