Brother, Can You Spare Some Cells to Fight Kidney Cancer?
Sept. 13, 2000 -- A form of treatment that works against some types of cancer that affect the immune system and the blood system may also be effective against kidney cancer that has spread to other parts of the body, an extremely difficult condition to treat with conventional therapies.
The experimental therapy, which uses donated cells from siblings to boost the patient's disease-fighting immune system, may also prove to be effective for treatment of other forms of cancers, suggest researchers.
Typically, half of all people with kidney cancer that has spread to other organs live less than one year from the time the disease is diagnosed. But in a study of 19 patients who received a transplant of immune cells from a closely matched sister or brother, nine of the patients were still alive more than one year later and two of them had no recurrence of disease more than two years after being treated.
Of the remaining 10 patients, two died from problems from the transplant, and eight from progression of the cancer. The results are published in the Sept. 14 issue of The New England Journal of Medicine.
Although the findings are encouraging, they are still preliminary. "This is a small group of patients and we have to very cautious about this," study co-author W. Marston Linehan, MD, chief of urologic surgery at the National Cancer Institute, tells WebMD. "Our follow-up is short -- it's only two-and-a-half years or so, but we are encouraged to date by the duration of response and by its magnitude. However, we're also cautious about the fact that we had two deaths in this trial ... and we're working hard to do better and prevent that in the future."
Kidney cancer can sometimes be cured by removing the kidney, if it's caught before it spreads. But kidney cancer that has spread removes that option, and it also usually does not respond to conventional treatments such as chemotherapy or radiation. Other researchers have shown that advanced kidney cancer can be effectively treated in only about 10-20% of all patients with drugs that boost the body's own immune defenses against cancer, a type of treatment known as immunotherapy.
In this recent study, the researchers used an offshoot of a complex (and controversial) form of treatment used to fight cancers affecting the immune system or blood system (like leukemia) by exposing patients to extremely high doses of chemotherapy to destroy the cancer. The problem is, though, that the treatment also kills off all the patient's bone marrow, where the cells of the immune system are formed. So the patient then receives new bone marrow, or immune cells -- either his own that have been purged of disease, or from a closely matched, disease-free donor such as a sibling, child, or parent. But because the patient's immune system has been wiped out, he must remain in isolation to avoid infections until the donor bone marrow has a chance to build him a "new" immune system.