Use of strontium-89 in endocrine-refractory prostate cancer metastatic to bone. Provincial Genitourinary Cancer Disease Site Group.

GUIDELINE QUESTION: What is the role of strontium-89 in effective palliative care of patients with stage D endocrine-refractory prostate cancer and multiple sites of painful bone metastases?

OBJECTIVE: To make recommendations about the routine use of 89Sr in this clinical setting.

OUTCOMES: Effective palliation is the primary outcome of interest. Patient survival and toxic effects of treatment are also considered.

PERSPECTIVE (VALUES): Evidence was selected and reviewed by 3 members of the Genitourinary Cancer Disease Site Group (Genitourinary Cancer DSG) of the Cancer Care Ontario Practice Guidelines Initiative. Earlier drafts of the guideline were circulated and reviewed by members of the DSG. The Genitourinary Cancer DSG comprises medical oncologists, radiation oncologists, urologists, a pathologist and a community representative. Guideline approval requires input from community representatives.

QUALITY OF EVIDENCE: Three randomized controlled trials (RCTs) were available for evaluation. Two compared 89Sr with placebo, and one RCT compared 89Sr with conventional radiation (either hemibody or involved-field radiotherapy, as determined before randomization).

BENEFITS: One of the 2 studies comparing 89Sr with placebo demonstrated the palliative efficacy of the intervention (p < 0.01); the other showed no benefit. The third study, comparing 89Sr with conventional radiation, concluded that all treatments provided equally effective pain relief and that improvement was sustained for at least 3 months in similar proportions of patients. The difference in the median duration of patient survival between groups in this study was neither clinically nor statistically significant.

HARMS: The use of 89Sr may cause bone marrow suppression, but clinically significant sequelae are uncommon. The use of 89Sr may preclude further systemic chemotherapy or eligibility for clinical trials of systemic therapy. Symptoms other than those due to bone marrow suppression are rare.

PRACTICE GUIDELINE: 89Sr is recommended for use in patients with endocrine-refractory prostate cancer who have multiple uncontrolled painful sites of bone metastases on both sides of the diaphragm not adequately controlled with conventional analgesic therapy, and in whom the use of multiple single fields of external beam radiation is not possible. 89Sr has proven to be efficacious in the palliation of hormone-refractory painful bone metastases from prostate cancer. It has not been shown to lengthen the average duration of patient survival. There is limited evidence on the relative efficacy of 89Sr compared with wide-field radiotherapy. 89Sr is the treatment of choice given all the following specific indications: Established diagnosis of prostate cancer metastatic to bone. Metastatic disease refractory to hormone therapy. Progressive sites of pain poorly controlled with conventional narcotics. Painful sites of disease on both sides of the diaphragm (otherwise, hemibody radiotherapy is equally efficacious). Patient or tumour factors (number of involved sites, location of involved sites or level of pain control) that are relative contraindications to the use of multiple single fields of radiation as an alternative. No evidence of impending spinal cord compression. Adequate bone marrow reserve. Evidence from a diagnostic bone scan of radionuclide concentration in painful bone lesions. PRACTICE GUIDELINE DATE: Nov. 23, 1997. Part 2.

GUIDELINE QUESTION: What is the role of 89Sr in effective palliative care of patients with stage D hormone-refractory prostate cancer receiving involved-field radiotherapy for isolated painful bone metastases?

OBJECTIVE: To make recommendations about the routine use of 89Sr in this clinical setting.

OUTCOMES: Effective palliation is the primary outcome of interest. Patient survival and toxic effects of treatment are also considered.

PERSPECTIVE (VALUES): As described in preceding abstract (Part 1).

QUALITY OF EVIDENCE: One RCT was available for evaluati