Dolezal, J. (2009). Efficacy and toxicity of ¹⁵³samarium-EDTMP in painful breast cancer bone metastases. Oncology Research and Treatment, 32, 35–39. 

To assess the usefulness of ¹⁵³Samarium-ethylene-diamino-tetramethylene phosphonic acid (¹⁵³Sm-EDTMP, a beta and gamma emitter) treatment in the palliation of painful bone metastases from breast cancer.

Study subjects with bone-disseminated breast cancer and bone pain refractory to opioid analgesics received  ¹⁵³Sm-EDTMP.  Karnofsky performance status, pain score, analgesic score and blood count were evaluated before treatment and one and three months after treatment.

• N: 43
• AGE: mean 60 years (41-79)
• FEMALE: 100%
• KEY DISEASE CHARACTERISTICS: Breast cancer with disseminated bone metastasis
• OTHER KEY SAMPLE CHARACTERISTICS: Inclusion criteria: Only patients with blastic or mixed lytic/blastic metastases were eligible for ¹⁵³Sm-EDTMP. Exclusion criteria: anemia (Hgb < 9.0 g/dl), leukocytopenia (WBC < 3.5 x 10⁹/l), thrombocytopenia (PLT < 150 x 10⁹/l), severe renal failure, Karnofsky performance status < 40%, simultaneous external-beam radiotherapy or chemotherapy, and treatment  with biphosphonate within 3-6 weeks prior to ¹⁵³Sm-EDTMP administration.

SITE: Single site

LOCATION: University Hospital Hradec Kralove, Czech Republic

PHASE OF CARE: Active treatment

APPLICATIONS: End of life, palliative care

Prospective, pre-post design

• Karnofsky performance rating
• Numeric rating scale (NRS) 
• World Health Organization analgesic score
• Blood count

Significant pain relief was observed in 51 (42%) of the patients, mild relief in 30 (30%), and no effect in 19 (28%) of the patients 1 and 3 months after administration, respectively. Mild and transient bone marrow suppression was observed as a side effect (majority had grade 1 or 2 hematologic toxicity, 1 patient had grade 3, and none had grade 4).

Alleviation of pain from bone metastasis can present a challenge, often requiring a multi-modality approach (i.e., palliative external-beam radiation, opioids, biphosphonates). Administration of bone-seeking radiopharmaceuticals have been reported in the literature over the past decade (i.e., ⁸⁹strontium chloride). ¹⁵³Sm-EDTMP reportedly has an affinity for skeletal tissue, particularly in osteoblastic bone formations. Patients with bone metastasis from breast cancer often have disseminated, multifocal metastatic sites, which may prove resistant to chemotherapy or endocrine/hormonal therapy. In these situations, external-beam therapy, while beneficial in local treatment, may not be as effective in palliating multiple sites. Therefore, bone radiopharmaceuticals such as ¹⁵³Sm-EDTMP would be a worthwhile consideration. From this study, it appears to be safe, well-tolerated, and effective in providing pain relief to a varying degree (was observed in 72% of participants).

Bone-seeking radiopharmaceuticals such as ¹⁵³Sm-EDTMP would be a worthwhile consideration in women with disseminated bone metastatses that have been refractory to chemotherapy or endocrine therapy for palliation of bone pain. Based on this study, it appears to be safe, well-tolerated, and effective in providing pain relief to a varying degree (was observed in 72% of participants).