ACS Panel on Prostate Cancer: Painful Skeletal Mets Require Special Management

PHILADELPHIA--Pain from skeletal metastasis has a major impacton quality of life in patients with prostate cancer, Mary Layman-Goldstein,RN, OCN, said at the American Cancer Society's National Conferenceon Prostate Cancer. Ms. Layman-Goldstein, a clinical nurse specialistat Memorial Sloan-Kettering Cancer Center, served on a panel discussionon how to manage complications of prostate cancer.

In addition to general principles of pain assessment and management,the clinician who treats patients with prostate cancer shouldbe familiar with adjuvant analgesic drugs used to treat bone pain,Ms. Layman-Goldstein said.

Short-term corticosteroid administration can be helpful in controllingsevere pain if there is difficulty establishing an effective opioiddose, she said.

By administering dexamethasone as an initial high-dose intravenousbolus, followed by tapered IV/PO doses every 6 hours, "theclinician can buy some time, break the pain cycle, and give thepatient a chance to become more tolerant to the effect of opioids."She cautioned, however, that long-term use of corticosteroidscan cause problems, which should be weighed against their potentialbenefits in relieving pain.

The bisphosphonates, etidronate (Didonrel) and pamidronate (Aredia),can reduce pain from skeletal metastases by inhibiting the activityof osteoclasts and decreasing bone resorption. These agents havebeen used successfully to reduce bone pain in patients with somekinds of cancer.

Calcitonin works in a similar fashion, by inhibiting osteoclasts,and also has a central antinociceptive effect. Before administeringcalcitonin, it is advisable to give a small trial dose to assessfor anaphylactic response. If there is no untoward reaction, calcitonincan be started at a dose of 25 IU and increased as necessary,she said. Many patients' pain can be relieved at doses of 100units three times a week, but some patients may need higher doses.

Radiopharmaceuticals are promising agents whose optimal role inpain management remains to be fully explored, Ms. Layman-Goldsteinsaid. Strontium-89 (Metastron), a bone-seeking radioisotope, hasbeen demonstrated to reduce opioid requirements in patients withbone metastases.

Radioisotopes should be used only after the patient has had abone scan that is positive for metastatic disease, she said. Bloodcounts should be within a certain range before beginning strontium-89therapy and should be monitored weekly thereafter.

Patients begin to experience relief between 1 and 3 weeks afterthe injection of strontium-89. The response lasts from 3 to 6months, after which the patient may be re-treated.A minority ofpatients given strontium-89 experience a flare in bone pain fora few days before responding to the infusion. These flares canbe managed by oral analgesics, she said.

Ms. Layman-Goldstein stressed that all of these adjuvant medicationsare in clinical use in the absence of comparative trials, andthe selection of an adjuvant therapy remains empirical.