Vaccine that is nearly 100 percent effective against all forms of cancer in rats and mice has been developed at the National Cancer Institute in Bethesda, Md., it was announced here yesterday.
Dr. Robert J. Huebner, who headed the research project, said the vaccine is "species-specific," meaning the mouse vaccine works only in mice and the rat vaccine only in rats.
However, the scientific principles that led to the development of these vaccines may make it possible to develop a similar vaccine for humans, he said at the American Cancer society's annual science writer's seminar.
Huebner said cancer-causing agents, including some chemicals and viruses, produce genetic changes that transform normal cells into cancer cells.
The damaged portion of this gene, which causes cancer cells to multiply out of control, can be removed from cancer cells by certain kinds of viruses which enter cells and pick-up genes as if they were hitchhikers.
This genetic material, once removed, can be used to make vaccine, huebner said. As an alternative, the cancerous cells themselves, with the damaged genes in them, can be used to make a vaccine, he added.
Meanwhile, a Canadian scientist reported limited success in using a lung tumor vaccine to treat early lung cancer and said he hopes in a few years to try to immunize high-risk people against the usually fatal disease.
Dr. Thomas H.M. Stewart of the University of Ottawa said 26 people treated with the experimental vaccine following surgery seemed to be getting recurrent lung cancer less frequently with fewer deaths than patients treated with surgery alone.
He said it may take two to four years for a larger study just beginning to confirm the early treatment results. And it may take seven to 10 addidtional years to see if the vaccine prevents the development of the most common form of lung cancer.