MONDAY, June 22, 2009 (HealthDay News) -- An experimental drug therapy appears to have helped destroy allegedly inoperable prostate cancer in two patients in a clinical trial.
Use of the immunotherapeutic agent MDX-010, or ipilimumab, in combination with standard hormone and radiation treatments helped eliminate the aggressive tumors, which had already spread into the patients' abdominal areas, according to a report from Mayo Clinic researchers that appears in Discovery's Edge, the Mayo Clinic's online research magazine. Both patients are now considered cancer-free.
"The tumors had shrunk dramatically," co-investigator Dr. Michael Blute, a Mayo urologist and surgeon who operated on both patients, said in a Mayo Clinic news release. "I had never seen anything like this before. I had a hard time finding the cancer. At one point, the pathologist [who was working during surgery] asked if we were sending him samples from the same patient."
Ipilimumab is an antibody that appears to greatly magnify the cancer-killing action of androgen ablation, a hormone therapy that helps shrink prostate cancer by eliminating testosterone from the body. Following the additional treatment, the patients showed steady decreases in their prostate-specific antigen (PSA) counts, a test used to detect prostate cancer, and were deemed eligible for surgery. After surgery, one patient underwent additional radiation therapy.
"This is one of the Holy Grails of prostate cancer research," clinical trial leader Dr. Eugene Kwon, a Mayo Clinic urologist, said of the antibody therapy in the same news release.
The team plans more research into how ipilimumab works and how to optimize its use.
The American Cancer Society has more about prostate cancer.