strontium-radioisotopes and Bone-Marrow-Diseases

Strontium-89 (Sr-89) chloride is an effective palliative treatment of the bone metastases of prostate cancer. Chemotherapy has also been shown to have a palliative benefit in this disease. We aimed to determine the benefits and complications of Sr-89 therapy in patients with prostate cancer who had become refractory to chemotherapy. We conducted a retrospective review of 14 treatments administered to 13 patients with chemotherapy-resistant and hormone-resistant prostate cancer.. Of the 14 administered treatments, 8 (57%) resulted in improved pain control, with 2 patients able to stop analgesia. The median duration of response was 56 days. No prostate-specific antigen response was seen in the 8 patients tested. There was significant and prolonged bone marrow toxicity, with 6 patients requiring red blood cell transfusion. Prolonged thrombocytopenia was seen, with platelet counts remaining below baseline levels after treatment in all but one patient. Leukopenia was generally mild and not associated with infection.. Sr-89 is an effective treatment of patients with chemotherapy-refractory prostate cancer, but careful and prolonged monitoring of hematologic parameters after therapy is required.

Topics: Adult; Aged; Antineoplastic Agents; Bone Marrow Diseases; Cohort Studies; Drug Resistance, Neoplasm; Hormones; Humans; Male; Middle Aged; Pain; Palliative Care; Prostate-Specific Antigen; Prostatic Neoplasms; Radiopharmaceuticals; Retrospective Studies; Strontium Radioisotopes; Survival Rate; Thrombocytopenia; Treatment Outcome

We present dosimetry for spinal metastases and red bone marrow in two patients who received 89Sr therapy for disseminated prostatic carcinoma. Absorbed dose to metastases was estimated by combining 85Sr gamma camera studies with computed tomographic measurements of bone mass, and doses of 20 cGy/MBq and 24 cGy/MBq were found for vertebral metastases that uniformly involved the bodies of L3 and D12 respectively. Absorbed dose to red bone marrow was estimated from total body strontium retention studies using the ICRP model for bone dosimetry, and a ratio of metastatic to marrow dose of around 10 was found in each patient. Although they received comparable treatment activities of around 200 MBq, the patients showed markedly different haematological response, this difference being confirmed when each received a second 89Sr treatment 6 months after the first. As a result, clinically significant thrombocytopenia occurred in one patient which prevented further radiostrontium therapy being given.

Topics: Adenocarcinoma; Aged; Bone Marrow Diseases; Brachytherapy; Energy Transfer; Follow-Up Studies; Hematologic Diseases; Humans; Male; Prostatic Neoplasms; Radiotherapy Dosage; Spinal Neoplasms; Strontium Radioisotopes; Tomography, X-Ray Computed; Whole-Body Counting

The toxicity of 90Sr administered by the inhalation route was studied in young adult Beagle dogs exposed once to aerosols containing 90SrCl2. Due to its relatively soluble chemical form, 90Sr was rapidly translocated from lung to bone where a substantial portion was retained for a long period of time. This resulted in only a brief radiation exposure of the respiratory tract and a protracted exposure of the skeleton. The long-term retained burdens ranged from 0.037 to 4.4 MBq 90Sr/kg body wt. Dogs were subsequently observed throughout their life span. Six dogs with long-term retained burdens of 1.7 to 4.1 MBq 90Sr/kg died at less than 32 days after exposure from radiation-induced bone marrow hypoplasia. Review of hematological parameters of all dogs showed a similar, consistent, and dose-related pancytopenia in those animals having a long-term retained burden of greater than 0.37 MBq 90Sr/kg. Thrombocytopenia and neutropenia persisted in all exposed dogs through 1000 days after exposure. For reference purposes, a burden of 0.37 MBq 90Sr/kg is calculated to deliver an average radiation dose to the skeleton over 30, 100, and 1000 days after intake of 1.0, 2.8, and 17 Gy, respectively. The hematologic changes were similar to those seen in people exposed to high doses of whole-body external radiation.

Topics: Administration, Inhalation; Aerosols; Animals; Blood Cell Count; Bone and Bones; Bone Marrow Diseases; Dogs; Dose-Response Relationship, Radiation; Lung; Radiation Injuries, Experimental; Strontium; Strontium Radioisotopes; Time Factors

Topics: Animals; Body Burden; Bone Marrow Diseases; Bone Neoplasms; Dogs; Dose-Response Relationship, Radiation; Neoplasms, Experimental; Neoplasms, Radiation-Induced; Radiation Injuries, Experimental; Radium; Soft Tissue Neoplasms; Strontium Radioisotopes; Time Factors; Toxicology

Topics: Bone Diseases; Bone Marrow Diseases; Half-Life; Humans; Radionuclide Imaging; Strontium Radioisotopes