Liepe, K., & Kotzerke, J. (2007). A comparative study of 188Re-HEDP, 186Re-HEDP, 153Sm-EDTMP and 89Sr in the treatment of painful skeletal metastases. Nuclear Medicine Communications, 28, 623–630.

• N = 79
• KEY DISEASE CHARACTERISTICS: Eighteen patients had breast cancer and 61 had prostate cancer.
• OTHER KEY SAMPLE CHARACTERISTICS:
  • In patients with bone metastasis, patients were already using long-term analgesics and had measurable pain symptoms, a positive bone scan with at least three lesions, and sufficient bone marrow and renal function.
  • Patients were excluded for bone fractures, spinal cord compression, and soft tissue tumors causing nerve compression.
  • Participants entered study at different levels of the World Health Organization (WHO) three-step ladder.
  • Bisphosphonates were stopped four weeks before treatment. Eighty-nine percent of patients had been treated with bisphosphonates for at least six months.
  • Nineteen percent of patients had chemotherapy, 27% had external beam therapy, and all stopped at least five months before treatment.
  • Patients with prostate cancer received hormone treatment for at least six months before treatment and also resumed treatment after postobservation or an orchiectomy.

• LOCATION: Germany

Prospective, nonrandomized study

• Weekly interviews including a Visual Analog Scale (VAS, 0–10) to assess pain relief, use of analgesics
• Karnofsky Performance Status (KPS), blood work, and bone scan before study and after 12 weeks
• Primary endpoint of pain relief was defined as at least two points on the VAS in two consecutive weeks without increase in analgesic use.

• Ten percent of patients had grade 1 thrombocytopenia, and 2% had grade 2.
• There were two patients with grade 1 leucopenia and one with grade 2.
• Most patients had grade 1 anemia.
• No statistical difference existed in the decrease of platelets or leukocytes between the four radiopharmaceuticals.
• For most patients, toxicity resolved 12 weeks after treatment.
• No evidence of local or systemic intolerance existed. However, 19% of patients had a flare reaction with a reversible increase of pain within 14 days after therapy.
• Pain relief (two points in two consecutive weeks without increase in analgesic use) occurred in 73% of patients and 15% were pain-free. The duration of response was greater than 12 weeks for 14 of the 24 patients who had a response. The rest of the patients had a duration of less than nine weeks.
• No significant difference was seen in response rate, pain relief, or duration between the four radiopharmaceuticals.
• KPS increased from baseline. There was no significant difference between the radiopharmaceuticals. However, the increase was significant with 188Re-HEDP (p < 0.001).
• Prostate patients: 23% showed a reduction in PSA of more than 50%.
• Bone scans were not different, although three single cases had a decrease in bone metastasis within 12 months after treatment.

• Non-randomized, unclear how authors chose which agent to receive
• Small number of breast cancer patients; did not stratify results based on disease type  
• Did not report breast cancer tumor marker response
• Did not report hormonal agents taken by breast cancer patients or oophorectomy
• In the group that received 89Sr, there were more patients with an analgesic-level 3 and a lower KPS than other groups.
• Unclear whether there a change in survival or a difference in progression-free interval
• More than one administration not noted
• Not all of these radionuclides are available for use.

These treatments produced mild and reversible side effects, and it is therefore a good option. It is usually used in palliation, but due to low side effects, there is possibility that it might be considered earlier in disease process. Future research could review concomitant treatment with chemotherapy.