Clinical trials using a new, highly targeted radiotherapy are currently being carried out in the United Kingdom. This new treatment will allow patients to be given a higher dose of radiation to destroy cancer cells in the bone marrow without harming healthy cells. The two-year trial at South General Hospital will involve 80 patients, half who will receive the new radiotherapy with chemotherapy and half with just chemotherapy.

There are several types of radiation treatments commonly used with multiple myeloma. Local radiation in high doses (often used in conjunction with chemotherapy) is used to treat solitary tumors in bone and soft tissue. High dose radiation to a large part of the body is used to reduce the number of tumor cells. Local low-dose therapy is used to relieve pain and treat bone fractures and spinal cord compression. Total body irradiation is used with high-dose chemotherapy in preparation for a stem cell transplantation in order to help kill myeloma cells in the bone marrow.

This new radiotherapy is used to kill cancer cells in the system before a stem cell transplant. The same dose of traditional radiotherapy would cause severe damage to the body, especially the liver and kidneys. The new system, however, only delivers the radioisotope to the surface of cancer cells, and the healthy tissue remains unaffected.

Dr. Kim Orchard, who is leading the trial, says that the sensitivity of healthy organs limits the dose of radiation that can be tolerated. "The key to this new treatment," he says, "is that the antibody accumulates only in the bone marrow." This new radiotherapy will also lead to more successful long-treatment, as one of the main reasons stem cell transplants fail is due to the continued presence of cancer cells in bone marrow before the transplant. The new radiotherapy will also be more effective, cheaper, and less toxic than traditional radiotherapies.

Pauline Pain of the Isle of Wight, a multiple myeloma patient, was the first person to receive this new treatment. She was able to return home immediately following her radiotherapy, whereas a conventional total body irradiation would have meant a longer hospital stay. Aside from temporary tiredness and mild sickness, Pain reported no remarkable side effects.

The treatment has started on patients with multiple myeloma, but may be extended to other blood and bone marrow diseases like leukemia.

For more information about these clinical trials, see the Telegraph.