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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Radiation is an effective modality for palliation of osseous metastases. In patients with a limited number of lesions, local external beam irradiation is the most expedient method of delivering radiation therapy. Complete or partial relief of pain will occur in 80-90% of patients. When metastases are widespread or when new sites continue to appear, localized external irradiation becomes logistically difficult. In such cases, hemibody irradiation has been effective with an overall response rate of 85%. However, nausea, vomiting, diarrhea, and bone marrow and pulmonary toxicity may complicate therapy. In these cases, an effective alternative is systemic phosphorus-32 (32P) or strontium-89 (89Sr). Relief of pain in the range of 60-90% has been reported. Toxicity of 32P is largely that of bone marrow suppression, while 89Sr appears to be relatively marrow-sparing. In this review, we consider systemic 32P or 89Sr as viable options to external beam or hemibody irradiation in the presence of numerous bone metastases.
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PMID:The palliation of osseous metastasis with 32P or 89Sr compared with external beam and hemibody irradiation: a historical perspective. 247 19

The total strontium plasma clearance rate due to excretion through the kidneys and gut has an important influence on the absorbed does delivered to skeletal metastases and red bone marrow in patients receiving 89Sr radionuclide therapy for disseminated prostatic carcinoma. Although a measurement of the renal strontium plasma clearance rate may readily be obtained through a 24-h urine collection, little information is available on the correlation between renal and total clearances. We describe a method of determining total strontium plasma clearance rate from whole body counter measurements of total body strontium retention and measurements of plasma strontium concentration following administration of a 85Sr tracer dose at the time of 89Sr therapy. Amongst the 26 patients whom we studied, the total clearance rate varied from 1.2-15.0 l/day, renal clearance rate from 0.1-11.5 l/day, and the mean gut clearance rate was 2.0 l/day. A close correlation was found between total and renal clearance, with the renal component accounting for 96% of the variance in total strontium plasma clearance. A weak collection may exist between gut and renal clearance.
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PMID:Measurements of the strontium plasma clearance rate in patients receiving 89Sr radionuclide therapy. 251 86

Strontium plasma clearance is an important factor determining the absorbed dose to metastases and bone marrow in patients receiving 89Sr radionuclide therapy for metastatic bone disease. Amongst male patients with disseminated prostatic carcinoma, the renal component of strontium clearance is frequently greatly reduced compared with values reported for healthy middle aged men. We report a study of renal and gut strontium plasma clearance, renal function, calcium urinary excretion, parathyroid function and extent of skeletal osteoblastic metastatic disease in patients referred for radiostrontium therapy for metastasised prostatic malignancy. The wide variation in net strontium clearance was principally due to variation in the renal component. Low values of strontium renal clearance were found to correlate with the elevation of serum PTH and nephrogenous cyclic AMP, which in turn correlated with extent of skeletal metastatic disease. This suggests that the osteosclerotic metastases characteristic of prostatic carcinoma induce secondary hyperparathyroidism due to the high avidity of the skeleton for calcium. The resulting reduction in strontium excretion may be beneficial to the objectives of radiostrontium therapy.
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PMID:89Sr therapy: strontium plasma clearance in disseminated prostatic carcinoma. 253 16

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.
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PMID:89Sr radionuclide therapy: dosimetry and haematological toxicity in two patients with metastasising prostatic carcinoma. 310 17

We report measurements of absorbed dose to vertebral metastases in ten patients referred for 89Sr therapy for disseminated prostatic carcinoma. Patients received a tracer dose of 85Sr at the time of 89Sr treatment and metastatic strontium retention was monitored scintigraphically for 6 mo. Metastatic 85Sr activity corrected for tissue attenuation was measured using the conjugate view principle, with special care taken to eliminate errors due to the selection of the metastatic region of interest. Metastatic volume was determined from high resolution CT images, and density inferred from Hounsfield number using the QCT bone mineral calibration of Genant and Cann. The mean absorbed dose was 850 rad/mCi (23 cGy/MBq) with a range from 220-2260 rad/mCi (6 to 61 cGy/MBq). The wide range found was consistent with the variation expected to arise due to differences in strontium renal plasma clearance (range 0.1-11.81/day) and extent of skeletal metastatic disease (varying from two small metastases to a superscan on [99mTc]MDP images) among the patients studied.
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PMID:Strontium-89 therapy: measurement of absorbed dose to skeletal metastases. 335 9

Amongst patients referred for 89Sr palliation of disseminated prostatic carcinoma, we have found wide variations in extent of skeletal metastatic disease and in strontium renal plasma clearance. A numerical technique using impulse response function analysis is reviewed which enables the effect of such variations on the total body, plasma and metastatic strontium retention functions to be calculated. The prediction of the model are compared with kinetic data from patients presenting for radiostrontium therapy, and correlations that have important implications for 89Sr dosimetric studies are confirmed. The simplest kinetic data required to allow for these effects in studies of dose-response and haematological toxicity following radio-strontium treatment are discussed and attention is drawn to a small group of patients who may form a significant exception to the general model.
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PMID:Strontium kinetics in metastasized prostatic carcinoma: a comparison with the predictions of impulse response function analysis. 344 27

We report a study of strontium kinetics in two patients who received 89Sr therapy for disseminated osteogenic sarcoma, together with estimates of absorbed dose to the principal metastases and to bone marrow. In neither patient did tumour uptake of strontium have a significant effect on whole-body retention. In one patient, whole-body strontium kinetics agreed closely with the ICRP standard model, while in the second, retention was extremely prolonged, probably due to hypertrophic osteoarthropathy. Strontium-85 scintigraphy, surface counting and high-resolution whole-body profiles agreed in showing that in both patients tumour turnover of strontium was very rapid, with a biological half-life of only a few days. Absorbed dose to tumour was found to be comparable in magnitude to the mean bone-marrow dose. We have no reason to believe that 89Sr therapy was of clinical benefit to either patient.
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PMID:Strontium-89 therapy: strontium kinetics and dosimetry in two patients treated for metastasising osteosarcoma. 347 Dec 88

Ten patients with disseminated bone metastases, nine from prostatic and one from renal cell carcinoma, were treated with intravenous strontium-89. Half the patients experienced significant improvement in pain control and increased general well-being for an average of 14 weeks. Sequential radiophosphate bone scanning showed decreased activity in lesions present at the time of therapy, with subsequent remineralization of the metastases on radiographs. Some patients showed simultaneous reduction in alkaline and acid phosphatase levels. These objective findings prove a physiologic basis for the clinical improvement. Treatments, however, did not prevent progression at initially uninvolved sites, particularly in the extremities.
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PMID:Sr-89 therapy for metastatic bone disease: scintigraphic and radiographic follow-up. 357 21

In a series of patients receiving 89Sr palliation for metastasised prostatic carcinoma, strontium renal plasma clearance was found to vary from 0.14 to 11.81 day-1, and the extent of skeletal metastatic disease seen on 99Tcm-MDP images varied from a few small metastases to a superscan. Using a numerical technique based on impulse response function (IRF) analysis, we have investigated the effect of such variation between patients on 89Sr dosimetry. The whole-body IRF, HWB(t), is defined by the deconvolution of the whole-body strontium retention function, RWB(t), with the plasma retention function, P(t). For patients with minimal metastatic bone disease we assumed HWB(t) = HO(t), where HO is the IRF derived from the International Commission on Radiological Protection model for normal strontium metabolism. The strontium plasma clearance, k, was allowed to vary, and the resulting variation of RWB(t), P(t) and absorbed dose to bone marrow calculated. By convoluting P(t,k) with the IRF measured for a discrete metastasis, the effect of varying k on tumour dose was investigated. Tumour and bone marrow dose were shown to change by a factor of three as k varied over the range observed in patients. For patients with extensive metastatic bone disease we assumed HWB(t) = (1-beta)HO(t) + beta HS(t), where HS was the IRF measured for a superscan patient and beta was a parameter reflecting the extent of skeletal metastatic disease. The effect of varying beta on tumour and bone marrow dose was investigated, and dose shown to decrease by a factor of five as beta increased from zero to unity. Impulse response function analysis was found to be a powerful and useful aid in clarifying the relationship between strontium kinetics and 89Sr dosimetry.
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PMID:Strontium-89 radionuclide therapy: a dosimetric study using impulse response function analysis. 362 Aug 27

We have utilized 89Sr as palliative treatment for bone pain secondary to metastatic cancer in the skeleton of over 200 patients. The best results have been in patients with carcinoma of the prostate (80% response rate) and breast (89%). Results in a small number of patients with a variety of other cell types were not nearly as encouraging. Strontium-89 provides excellent palliation in the management of bone pain secondary to prostate and breast carcinoma.
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PMID:Treatment of metastatic bone pain with strontium-89. 366 5


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