New Radiation Therapy Directly Attacks Cancer Cells

(EPA)

Researchers at Tel Aviv University in Israel have developed a new method of tumor removal that improves the likelihood of permanently destroying the tumor, and reduce the odds of it returning. The ablation process devised by Tel Aviv medical researcher Yona Keisari and physicist Itzhak Kelson is described in the journal Translational Research (paid subscription required), and being commercialized by a company they founded.

Keisari and Kelson’s process uses a radioactive wire, less than an inch long and about the width of a pin. When inserted into a solid tumor, the wire releases radioactive atoms that irradiate the tumor from the inside out.

Their method also helps build protection in the patient against the tumor returning. As the tumor breaks down, it releases antigens which trigger an immune response against the cancerous cells. Not only are cancerous cells more reliably destroyed, says Keisari, but in most cases the body develops immunity against the return of the tumor, which rarely occurs when the tumor is removed surgically.

Current radiation therapy uses gamma rays, which are less effective and targeted than the alpha particles employed by the Tel Aviv team. Alpha particles, however, have a much shorter range and are unable to penetrate the skin, which up to now has made them inapplicable for cancer therapy. The radioactive wire method developed in Kelson’s lab puts the radioactive ions directly into the tumor, thus overcoming that obstacle.

As Kelson explains, the wire is coated with a substance that emits alpha particles and related atoms that “diffuse inside the tumor, spreading further and further before disintegrating.” The process takes about ten days, leaving non-radioactive and non-toxic amounts of lead. The wire itself, which is initially inserted into the tumor by hypodermic needle, decays harmlessly in the body.

In the lab, Keisari and Kelson tested the procedure on mice, with one group using surgical removal and the other group treated with radioactive wire/ablation treatment. When cancer cells were re-injected into the subjects, 100 percent of those that had surgical removal redeveloped their tumors, compared to about half of those treated with the radioactive wire.

The researchers say they recorded favorable results with many types of cancer models, including lung, pancreatic, colon, breast, and brain tumors. To take the treatment method to the next stages, Keisari and Kelson founded the company Althera Medical, based in New York and Bnei-Brak, Israel near Tel Aviv. The treatment, called Diffusing Alpha-emitters Radiation Therapy, expects to undergo clinical trials at Beilinson Hospital in Israel.

Read more: Early Success Recorded with Lasers on Kidney, Liver Tumors

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