Facts on File Encyclopedia of Health and Medicine

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presses the maturation of lymphocytes to plasma
cells. Thalidomide analogs (such as Revimid and
Actimid) are drugs closely related in chemical
structure to thalidomide. Oncologists may admin-
ister thalidomide in combination with prednisone
or dexamethasone, corticosteroid medications that
help suppress bone marrow activity to slow the
production of cancerous plasma cells.
Proteasome inhibitors In 2003 the US Food
and Drug Administration (FDA) approved the pro-
teasome inhibitor bortezomib (Velcade) for people
who have experienced two relapses following con-
ventional treatment approaches. Proteasome
inhibitors block the actions of enzymes within
cells that are crucial to the cell’s ability to divide
(reproduce). Clinical studies continue to investi-
gate the effectiveness of these drugs, which appear
to cause fewer side effects than conventional
chemotherapy, as first-choice treatment.
Bone marrow and stem cell transplantation
Autologous BONE MARROW TRANSPLANTATIONor STEM
CELL transplantation (self-transplantation with
harvested cells), achieves remission in many peo-
ple. For autologous transplantation, the oncologist
harvests peripheral BLOOD STEM CELLS (PBSC) or
stem cells from healthy areas of bone marrow;
administers high-DOSE chemotherapy after cell
harvesting to kill the cancerous bone marrow; and
administers the harvested bone marrow or stem
cells, which then grow to replace the cancerous
bone marrow. Allogeneic stem cell transplanta-
tion, which uses stem cells from a tissue-matched
donor, carries relatively high risks of complications
including transplant rejection, infection, and other
reactions, but is so far the only hope for a cure
of multiple myeloma. Nonmyeloablative (the
patient’s bone marrow is not destroyed) allogeneic
stem cell transplantation reduces the high risks of
high-dose chemotherapy. Though not curative it
may offer increased survival time.
Adjunctive therapies Oncologists use various
medications to mediate the side effects of treat-
ment as well as the complications that arise as the
course of the cancer progresses. Among them are:



  • Statins (such as Lipitor and Mevacor) counters
    the osteoclastic (bone destruction) stimulation
    M-proteins generate. Researchers discovered in
    the early 2000s that the statin medications used


to treat HYPERLIPIDEMIA(elevated blood choles-
terol and blood lipid levels) additionally stimu-
late osteoblastic (bone construction) activity,
resulting in increased production of new bone
tissue.


  • Therapeutic EPO supplementation (Procrit)
    stimulates bone marrow production of erythro-
    cytes, relieving anemia.

  • Bisphosphonates bind to damaged bone cells
    and so prevent further osteoclastic action
    (destruction). This allows the body’s natural
    bone remodeling mechanisms to repair the
    damage and rebuild the bone. However, bis-
    phosphonates present the potential for serious
    kidney damage.


•ANTIBIOTIC MEDICATIONS aggressively treat the
infections that become increasingly common as
dysfunction of the IMMUNE SYSTEMprogresses.

Lifestyle factors Because multiple myeloma
affects bone remodeling, daily weight-bearing
exercise such as walking is important to stimulate
the body’s normal osteoblastic (bone-constructing)
mechanisms. These mechanisms further help bone
tissue retain calcium, reducing the amounts of cal-
cium that leaches into the circulation. Drinking
lots of water to maintain high HYDRATIONis also
especially important. Staying well hydrated helps
offset the tendency of the blood to become hyper-
viscous (thickened) as a consequence of the
changes in its constitution that take place with the
multiple myeloma. It also helps protect the kid-
neys by lowering the concentration of calcium and
M-proteins that they must filter from the blood
and pass in the URINE. Nutritious EATING HABITSpro-
vide the body with the NUTRIENTSit needs to main-
tain the best health status possible.

Risk Factors and Preventive Measures
Though environmental exposure, notably to pesti-
cides and radiation, appears to play a role in the
development of multiple myeloma, researchers do
not know the mechanisms of such exposure.
Many people who develop multiple myeloma do
not have a known history of exposure to sub-
stances so far linked with an increased risk for this
form of cancer, making it difficult for health

multiple myeloma 159
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