The PANVAC vaccine, administered to 26 women through monthly shots, helped the body's immune system recognize proteins produced specifically by cancer cells, said study author Dr. James Gulley, director and deputy chief of the clinical trials group at the Laboratory of Tumor Immunology and Biology at the U.S. National Cancer Institute.
All of the women had breast or ovarian cancer that had spread to other organs and were considered "heavily pre-treated" with other therapies, with 21 having received at least three chemotherapy regimens. In addition to the four breast cancer patients whose disease stopped progressing, one woman with breast cancer experienced a "complete response," meaning her cancer disappeared.
The study is published Nov. 8 in the journal Clinical Cancer Research.
"Anytime we have one type of biologic treatment demonstrate some success, it's exciting," said Dr. Elizabeth Poynor, a gynecologic oncologist and pelvic surgeon at Lenox Hill Hospital in New York City, who was not involved in the study. "No matter how small the study is -- and early studies will be small -- when we have positive results on a particular technique, it's a very hopeful thing. These are our most difficult patients to treat; they have failed multiple therapies."
Indeed, most participants -- whose average age was 57 -- had exhausted other forms of treatment, Gulley said, which likely hampered their immune systems from responding as fully to the vaccine as they otherwise might have. As therapeutic vaccines become more established, Gulley said they might prove even more effective in patients whose disease is less advanced....read more