A new approach to bone pain has arrived with the development of a compound called radioactive strontium-89—a radioactive isotope that is injected into the body as an outpatient procedure.

Strontium-89 is specially tailored for bone pain. Like calcium, it is taken up immediately by bone, as water is absorbed by a sponge—except this compound tends to zoom right past healthy bone and zero in on metastatic cancer. (Strontium-89 is soaked up by tumor in bone, instead of by bone marrow, at a ratio of ten to one.) Relief from pain has been reported in from half to 80 percent of patients.

Strontium-89 has a long half-life—fifty-one days—in the body; a single shot of the compound has proved effective at relieving pain for an average of six months. One advantage of this, as compared to spot radiation, is that it acts on new sites of metastasisthat crop up while it stays in the body, as well as the older sites of cancer it originally was intended to treat.

And, strontium-89 can be used in combination with spot radiation In one study, doctors found that this combined approach—strontium-89 plus spot radiation—delayed progression of pain seven months longer than radiation alone.

Side Effects. The few side effects associated with strontium-89 include the potential for bone marrow damage; this is characterized by a drop in platelets. Also, some men report a mild increase in pain for the first couple of days after receiving the injection; this can be controlled with other pain medication. And a safety note: Because this radioactive substance is excreted in the urine, for the first forty-eight hours after receiving the injection urine must be taken care of in a certain way; this means you must urinate into a special container—not into the toilet—and dispose of this as directed by your doctor.

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