A new drug “tricks” bones into fighting the cancer’s spread.
In May 2013, the U.S. Food and Drug Administration approved a new drug
for the treatment of prostate cancer that had spread to the bone. It immediately
got the attention of
Alison Grann, M.D., chair of
radiation oncology at Saint Barnabas Medical Center. “I was excited about this medication, because it would improve
quality of life and patients would be more comfortable, so I really pushed
to get this here,” she says.
Her zeal helped persuade the medical center to become one of the first
in New Jersey to administer the radioactive isotope radium 223, which
goes by the brand name Xofigo (pronounced zoh-FEE-go). In a study published
in the New England Journal of Medicine, it significantly decreased pain
and improved survival rates for men whose prostate cancer had spread to
the bone and was resistant to other medical or surgical treatments.
Prostate cancer often spreads to bone first; “it has an affinity
for bone tissue,” Dr. Grann says. The first line of treatment when
this happens is medication that blocks testosterone, which encourages
the growth of prostate cancer cells. “However, at some point the
cancer often becomes resistant to these medicines,”Dr. Grann says.
Bone cancer is typically quite painful, but until Xofigo there was little
that could be done to help patients other than administering narcotics.
This new drug, however, can slow the cancer’s progress in the bone.
It works through trickery, Dr. Grann says. The bone tissue mistakes the
radium for calcium, and takes it in readily where bone is growing rapidly
from cancer. Once it is in the bone, it releases radiation, but in very
small and localized doses that spread less than 100 microns—about
the width of a human hair—to kill the cancer while doing little
or no damage to healthy cells.
The treatment consists of six intravenous injections, one every four weeks.
Dosage is based on weight, so patients are weighed before each injection,
which takes about a minute. “Side effects are nausea and diarrhea,
though both are pretty uncommon, and also lowering of blood counts, so
we do a blood check before every injection,” Dr. Grann says.
Though the overall prognosis for patients with metastatic prostate cancer
is variable, Xofigo “gives them a new option with limited toxicity
that potentially can improve their quality of life,” says the doctor.
“They can remain on their other medications, which may be controlling
their disease well except for the pain. Now they can also go out and walk
or play golf or do their thing.”
For more about radiation oncology services at Saint Barnabas Medical Center,
call 973.322.5630 or visit the
Radiation Oncology Department.