At the time of diagnosis a large proportion of patients have locally advanced or metastatic disease with skeletal metastases frequently a cause of significant pain. This pain may be deep and unremitting and a cause of significant morbidity.
Prostate malignancy is described as having a biclonal composition with hormone-sensitive and hormone-resistant cell lines. Surgical (orchidectomy) and medical hormone manipulation has a role in management, often achieving rapid subjective and objective therapeutic response. A significant proportion of patients never respond to hormone manipulation and the majority of patients who do respond initially will later escape from hormonal control and later develop progressive, usually symptomatic disease.
With painful skeletal metastases, external beam radiotherapy may serve to control limited disease and analgesic (narcotic) medications have an obvious benefit. However when skeletal metastases are widespread or side effects from narcotics exceed benefit, the option of Strontium therapy should be considered a viable alternative.
Mechanism of action Strontium imitates the in-vivo behaviour of calcium and is preferentially taken up by bone, concentrating at sites of high skeletal metabolic activity. The radioactive half life of Strontium is 50.5 days with a biological half life of about 14 days in normal bone due to renal and to a lesser extent biliary excretion. Due to the high affinity of osteoblastic skeletal metastases for this isotope, Strontium is retained almost indefinitely within metastatic bone. Strontium - 89 is a pure beta particle emitter with negligible gamma radiation emission. Beta particles have a range of 3.5 mm in bone and 6-7 mm in soft tissues. Consequently there is targeted irradiation of metastatic lesions with minimal irradiation of healthy tissues distant to metastases. Mechanism of administration Strontium is given as a single slow intravenous injection followed by saline flush using strict guidelines for handling and administration of unsealed radioactive sources. Prior to administration the patient is informed of potential benefits and the patient and family or caregivers are give appropriate radiation safety advice. In view of the potential myelo-suppression associated with use, repeat doses of Strontium for pain recurrence are withheld for at least 3-4 months and ideally 6 months from initial dose. Potential side effects of Strontium The most notable side effect of Strontium is mild haematological suppression with a fall in circulating platelet and leukocyte counts recognized in most patients. With usual therapeutic doses, platelets typically fall by 30% and leucocytes by 20%. Clinically significant toxicity is rare, however its use is not recommended in patients with severely compromised bone marrow and preliminary platelet count prior to therapy. Progress monitoring at 4-6 weeks following therapy is suggested. Patient selection Patients referred for Strontium therapy should be under the care of a specialist urological surgeon, medical or radiation oncologist. The patient should have painful skeletal metastases from known prostate carcinoma, shown to be osteoblastic on recent bone scan and should have had appropriate hormone manipulation and narcotic analgesia as required as a first pain management. Up to 80% of patients receiving Strontium - 89 will achieve a response with significant reduction in metastatic skeletal pain, with about 20% of these becoming pain free. In addition it is recognized that Strontium not only is effective in treating painful metastases but also has a therapeutic effect on metastases that have not yet become painful. This is evident as a reduction in the appearance of new sites of skeletal pain in the short term following Strontium compared with placebo group patients. The onset of therapeutic response is about 10 days following administration and maximal at 6-12 weeks. Conclusion Strontium - 89 has no significant effect on patient survival. The objective then is to achieve a reduction in the frequency and potency of analgesia required. With significant pain alleviation and the potential for improved physical activity, there is potential for substantial improvements in overall quality of life. Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
Strontium - 89 is a pure beta particle emitter with negligible gamma radiation emission. Beta particles have a range of 3.5 mm in bone and 6-7 mm in soft tissues. Consequently there is targeted irradiation of metastatic lesions with minimal irradiation of healthy tissues distant to metastases.
Mechanism of administration Strontium is given as a single slow intravenous injection followed by saline flush using strict guidelines for handling and administration of unsealed radioactive sources. Prior to administration the patient is informed of potential benefits and the patient and family or caregivers are give appropriate radiation safety advice. In view of the potential myelo-suppression associated with use, repeat doses of Strontium for pain recurrence are withheld for at least 3-4 months and ideally 6 months from initial dose. Potential side effects of Strontium The most notable side effect of Strontium is mild haematological suppression with a fall in circulating platelet and leukocyte counts recognized in most patients. With usual therapeutic doses, platelets typically fall by 30% and leucocytes by 20%. Clinically significant toxicity is rare, however its use is not recommended in patients with severely compromised bone marrow and preliminary platelet count prior to therapy. Progress monitoring at 4-6 weeks following therapy is suggested. Patient selection Patients referred for Strontium therapy should be under the care of a specialist urological surgeon, medical or radiation oncologist. The patient should have painful skeletal metastases from known prostate carcinoma, shown to be osteoblastic on recent bone scan and should have had appropriate hormone manipulation and narcotic analgesia as required as a first pain management. Up to 80% of patients receiving Strontium - 89 will achieve a response with significant reduction in metastatic skeletal pain, with about 20% of these becoming pain free. In addition it is recognized that Strontium not only is effective in treating painful metastases but also has a therapeutic effect on metastases that have not yet become painful. This is evident as a reduction in the appearance of new sites of skeletal pain in the short term following Strontium compared with placebo group patients. The onset of therapeutic response is about 10 days following administration and maximal at 6-12 weeks. Conclusion Strontium - 89 has no significant effect on patient survival. The objective then is to achieve a reduction in the frequency and potency of analgesia required. With significant pain alleviation and the potential for improved physical activity, there is potential for substantial improvements in overall quality of life. Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
In view of the potential myelo-suppression associated with use, repeat doses of Strontium for pain recurrence are withheld for at least 3-4 months and ideally 6 months from initial dose.
Potential side effects of Strontium The most notable side effect of Strontium is mild haematological suppression with a fall in circulating platelet and leukocyte counts recognized in most patients. With usual therapeutic doses, platelets typically fall by 30% and leucocytes by 20%. Clinically significant toxicity is rare, however its use is not recommended in patients with severely compromised bone marrow and preliminary platelet count prior to therapy. Progress monitoring at 4-6 weeks following therapy is suggested. Patient selection Patients referred for Strontium therapy should be under the care of a specialist urological surgeon, medical or radiation oncologist. The patient should have painful skeletal metastases from known prostate carcinoma, shown to be osteoblastic on recent bone scan and should have had appropriate hormone manipulation and narcotic analgesia as required as a first pain management. Up to 80% of patients receiving Strontium - 89 will achieve a response with significant reduction in metastatic skeletal pain, with about 20% of these becoming pain free. In addition it is recognized that Strontium not only is effective in treating painful metastases but also has a therapeutic effect on metastases that have not yet become painful. This is evident as a reduction in the appearance of new sites of skeletal pain in the short term following Strontium compared with placebo group patients. The onset of therapeutic response is about 10 days following administration and maximal at 6-12 weeks. Conclusion Strontium - 89 has no significant effect on patient survival. The objective then is to achieve a reduction in the frequency and potency of analgesia required. With significant pain alleviation and the potential for improved physical activity, there is potential for substantial improvements in overall quality of life. Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
Patient selection Patients referred for Strontium therapy should be under the care of a specialist urological surgeon, medical or radiation oncologist. The patient should have painful skeletal metastases from known prostate carcinoma, shown to be osteoblastic on recent bone scan and should have had appropriate hormone manipulation and narcotic analgesia as required as a first pain management. Up to 80% of patients receiving Strontium - 89 will achieve a response with significant reduction in metastatic skeletal pain, with about 20% of these becoming pain free. In addition it is recognized that Strontium not only is effective in treating painful metastases but also has a therapeutic effect on metastases that have not yet become painful. This is evident as a reduction in the appearance of new sites of skeletal pain in the short term following Strontium compared with placebo group patients. The onset of therapeutic response is about 10 days following administration and maximal at 6-12 weeks. Conclusion Strontium - 89 has no significant effect on patient survival. The objective then is to achieve a reduction in the frequency and potency of analgesia required. With significant pain alleviation and the potential for improved physical activity, there is potential for substantial improvements in overall quality of life. Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
Up to 80% of patients receiving Strontium - 89 will achieve a response with significant reduction in metastatic skeletal pain, with about 20% of these becoming pain free. In addition it is recognized that Strontium not only is effective in treating painful metastases but also has a therapeutic effect on metastases that have not yet become painful. This is evident as a reduction in the appearance of new sites of skeletal pain in the short term following Strontium compared with placebo group patients. The onset of therapeutic response is about 10 days following administration and maximal at 6-12 weeks. Conclusion Strontium - 89 has no significant effect on patient survival. The objective then is to achieve a reduction in the frequency and potency of analgesia required. With significant pain alleviation and the potential for improved physical activity, there is potential for substantial improvements in overall quality of life. Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
Conclusion Strontium - 89 has no significant effect on patient survival. The objective then is to achieve a reduction in the frequency and potency of analgesia required. With significant pain alleviation and the potential for improved physical activity, there is potential for substantial improvements in overall quality of life. Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
Dr John Mulholland is a radiologist and specialist in nuclear medicine at North Coast Radiology. Top of Page Previous Index 1Terminal restlessness Palliative CareIndex NextSecondary malignancy from an unknown primary site
