Serum Phosphate testing and bone density screenings

[Guest guest]

Hi everyone!

Has anyone had serum phosphate testings or bone density screenings,

(even if you aren't 50+) since the information regarding Gleevec has

come to light? I'm referring to the article below. Just curious

what your results have been. (If you've had the tests performed)

Thanks! Lynn

Are Hem/Onc's recomending these tests now? Has it been discussed as

a new protocol for CML?

Cancer Drug Gleevec Can Interfere With Bone Growth

By Ed Edelson

HealthDay Reporter

WEDNESDAY, May 10 (HealthDay News) -- Gleevec, the drug that has

brought life and hope to patients with some otherwise untreatable

cancers , can interfere with bone formation, researchers have found.

It's a side effect, they say, that deserves careful watching but

should not stop use of the medication.

" This is a new type of side effect that we discovered in part because

some of our patents on Gleevec developed low levels of serum

phosphate, a mineral important in bone synthesis and modeling, " said

Dr. Ellin Berman, a member of the leukemia service at Memorial Sloan-

Kettering Cancer Center in New York City. She's also lead author of a

paper on the finding that appears in the May 11 issue of the New

England Journal of Medicine.

" In some patients it developed very quickly, " Berman said. " In some

patients, phosphate levels were very, very low. Then we brought in

kidney specialists and then bone specialists. What we found was

surprising. It had not been described before. "

The patients were being treated for chronic myelogenous leukemia

(CML), a blood cancer whose outlook has been transformed by Gleevec.

The drug has changed the potential life expectancy of CML patients

from a few years to perhaps decades.

The detection of the drug's effect on bone means patients being

treated with Gleevec for either CML or intestinal cancers called

gastrointestinal stromal tumors " have to be screened for

abnormalities of bone, " Berman said. " What Gleevec appears to do is

inhibit bone synthesis and bone remodeling. "

The new finding focused on just 16 patients who were found to have

low serum phosphate levels, and its ultimate importance has yet to be

determined, Berman said. " This suggests that Gleevec may have long-

term effects on bone, not bone marrow but bone structure itself, " she

said. " We are trying to put the entire picture together. Is everyone

on Gleevec at risk, or just some people? Do we need to look at the

entire bone structure? "

But doctors at Memorial Sloan-Kettering are continuing to use

Gleevec -- with careful monitoring of bone structure and

function. " Bone is a dynamic organ, which is constantly being made

and remodeled, " Berman said.

Dr. Marshall Lichtman, executive vice president of research and

medical programs at the Leukemia and Lymphoma Society, called the

Sloan-Kettering report " an important observation. It certainly will

be helpful for physicians caring for patients with CML. But what we

don't know yet are the implications of this over the long run. "

Side effects such as the one reported now " are probably predictable,

because we are inhibiting enzymes in normal tissue as well as

diseased tissue, " Lichtman said. " The remarkable thing is how well-

tolerated this drug is, considering that it inhibits the action of

critical enzymes. "

Only mild side effects of Gleevec have been reported before, such as

gastrointestinal upset and slight protrusion of the eyes. While the

ultimate impact of the newly reported effect is unknown, " we have to

take steps to prevent any long-term significant bone disease, "

Lichtman said.

Berman said there may even be a positive side to the

discovery. " Gleevec may have a role in disease where bone synthesis

and turnover need to be turned off, " she said. For example, it could

be helpful when cells from a cancer elsewhere in the body move into a

bone. Stopping bone synthesis could help control that problem, she

said.

SOURCES: Ellin Berman, M.D., member, leukemia service, Memorial Sloan-

Kettering Cancer Center, New York City; Marshall Lictman, M.D.,

executive vice president, research and medical programs, Leukemia and

Lymphoma Society, White Plains, N.Y.; May 11, 2006, New England

Journal of Medicine