Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A Phase I and II study has been conducted of the safety and efficacy of 89Sr (injected i.v. as the chloride) to alleviate bone pain due to osseous metastatic disease. Potential attendant hematologic toxicity was also examined. Strontium-90 impurities were always less than 1.5%, employing a new quality control technique which detects the 90Y "daughter". Thirty-eight patients with pain due to osseous metastases requiring regular narcotic more than twice a day, documented by an abnormal bone scan and radiography, received 45 doses (1-4.5 mCi, 16-70 microCi/kg) of 89Sr after informed consent. The performance status (Karnofsky scale) ranged from 20-80%. One patient had complete pain relief while 22 other doses yielded at least a 25% reduction in narcotic requirement lasting at least 1 mo and/or 20% improvement in Karnofsky scale rating. Two patients had marked to complete relief in tumor sites which were not fractured, with no change in fracture pain. Twenty-two did not respond. Response was independent of narcotic requirements, tumor type, or Karnofsky status. No hematologic toxicity occurred. Strontium-89 may be useful as adjuvant therapy for diffuse bone pain, but a double-blind study comparing it to other nonnarcotic modalities is required.
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PMID:Strontium-89 therapy for the pain of osseous metastases. 392 Mar 61

Experience with x-rays, strontium-87m scintigraphy, and technetium-99m polyphosphate scintigraphy in the identification of bone metastases in 201 patients with prostatic cancer is reviewed. About 40% of the patients had demonstrable metastases in bone at the time of first presentation.Comparative studies of 247 x-ray and (87m)Sr surveys indicated that x-rays failed to detect metastases in 10% of cases where they were identified by (87m)Sr but that the isotopic survey similarly failed to detect radiologically evident deposits in 7% of cases.Similar studies comparing (99m)Tc polyphosphate surveys with x-ray scans showed that x-rays missed isotopically detected metastases in 12% of cases, but in only one survey out of 67 did the isotope miss radiologically evident deposits. In a series of 32 patients investigated by both isotopic techniques (99m)Tc polyphosphate did not fail to detect any metastases and identified deposits in one patient in whom they were missed by (87m)Sr scintigraphy. About 15% of both x-ray and (87m)Sr surveys gave equivocal results, but only 3% (2 out of 67) of (99m)Tc polyphosphate surveys were equivocal.We concluded that (99m)Tc polyphosphate bone scintigraphy with the gamma camera was the most reliable of the techniques used for the identification of bone metastases in patients with carcinoma of the prostate. The results of scintigraphy with (87m)Sr suggested that serial surveys may provide early evidence of hormone resistance in prostatic cancer.
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PMID:Radioisotopic bone scintigraphy with the gamma camera in the investigation of prostatic cancer. 483 42

The biologic effects of stable strontium, a naturally occurring trace element in the diet and the body, have been little investigated. This paper discusses the effects of oral supplementation with stable strontium in laboratory studies and clinical investigations. The extent of intestinal absorption of various doses of orally administered strontium was estimated by determining serum and tissue levels with atomic absorption spectrophotometry. The central observation is that increased oral intake produces a direct increase in serum levels and intracellular uptake of strontium. The results of these studies, as well as those of other investigators, demonstrate that a moderate dosage of stable strontium does not adversely affect the level of calcium either in the serum or in soft tissues. In studies of patients receiving 1 to 1.5 g/d of strontium gluconate, a sustained increase in the serum level of strontium produced a 100-fold increase in the strontium:calcium ratio. In rats, studies indicate that an increase in intracellular strontium content following supplementation may exert a protective effect on mitochondrial structure, probably by means of a stabilizing effect of strontium on membranes. The strontium:calcium ratio in animals receiving a standard diet is higher in the cell than in the extracellular fluid; this may be of physiologic significance.An increase in density that corresponded to the deposition of stable strontium was observed in areas of bone lesions due to metastatic cancer in patients receiving stable strontium supplementation. This suggests the possibility of using strontium to mineralize osteophenic areas and to relieve bone pain. Also, because of reports of an inverse relation between the incidence of dental caries and a high strontium content in drinking water, the use of natural water containing relatively high levels of stable strontium should be considered. In each of these instances it is important to maintain a normal dietary intake of calcium.
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PMID:Effects of oral supplementation with stable strontium. 612 36

Bone metastases that develop in patients with advanced prostate cancer often cause deep, unremitting pain. Palliative options for the control of this pain include analgesic support, cytotoxic chemotherapy and external-beam radiotherapy. In addition to external irradiation, interest in intravenously injected radioisotopes that are preferentially localized to bone has been mounting. Metastron (an isotope of strontium) imitates the biodistribution of calcium in vivo and is avidly taken up into bony metastases where it has a biological half-life of just over 50 days. The biological half-life in undiseased bone is far shorter, approximately 14 days. Various studies have been conducted to evaluate the role of Metastron in metastatic prostate cancer. An optimum dose has yet to be finalized, but it is clear that the change of haematological toxicity becomes more significant at much larger doses. In the large, randomized Trans Canada study in which Metastron or placebo was given to patients as an adjunct to local field irradiation, those patients treated with Metastron had a significantly reduced intake of analgesics. Furthermore, progression of pain, as measured either by sites of new pain or by the requirement for further palliative radiotherapy, demonstrated statistically significant differences in favour of Metastron. There is thus increasing evidence of a useful role for Metastron in the treatment of prostate cancer metastatic to bone.
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PMID:Strontium-89 (Metastron) in the treatment of prostate cancer metastatic to bone. 753 65

Radiation therapy is a proven technique to relieve the pain of bone metastases. Focal painful metastases can be palliated in up to 80 percent of patients. The technique to use for the treatment varies depending on the extent of disease, the prognosis of the patient and physician preference. Most studies indicate that the local treatment of bone metastases with single large treatments is as efficacious as extended courses of treatment. For patients with wide-spread disease, two forms of systemic radiotherapy are available: hemibody irradiation and intravenous injection of radionuclides. Studies have shown the combination of either focal irradiation and hemibody irradiation or focal irradiation and the injection of strontium (89) prolongs the pain-free duration of the patients. All palliative patients with symptomatic bone metastases should be evaluated for radiotherapy.
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PMID:Prospective trials for the radiotherapeutic treatment of bone metastases. 754 72

Bony metastasis is the most common cause of cancer pain. Strontium-89 (Sr-89), or Metastron, therapy has been shown to be effective for the palliation of pain due to skeletal metastases. By reducing opioid analgesics intake and restoring mobility, Sr-89 improves the patient's quality of life. Sr-89 is given conveniently as an outpatient procedure, and when necessary it can be repeated at 3-month intervals. Sr-89 is useful as an adjunct to local external beam radiation (EBR) because Sr-89 will target all skeletal metastases, including those not included in the EBR field. Because Sr-89 is a beta-emitting radionuclide with a long physical half-life (50.5 days), precautions should be taken by the caretaker(s) against Sr-89 contamination from the patient's blood or excretions, particularly if the patient is incontinent.
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PMID:Palliation of bone pain in patients with metastatic cancer using strontium-89 (Metastron). 754 83

The systemic administration of 89Sr has proven effective in the palliation of painful osseous metastases. Biodistribution studies with the gamma-emitter 85Sr suggest that both its uptake and retention are increased in bone metastases, where increased mineral turnover takes place. To study the pattern and nature of this process further, bones containing metastatic deposits were obtained from three patients who had previously been treated with 148 MBq of 89Sr. The bones were cut into 0.5-1.0 cm sections. The cut surfaces which faced together were marked with India ink, and adjacent sections were submitted for histology and autoradiography. Strontium deposition and retention were observed in regions which exhibited significant osteoblastic activity, mostly in areas adjacent to metastatic deposits, but also in subchondral and endosteal locations, as well as in an area corresponding to a pathological fracture with callus formation. With these exceptions, strontium deposition was not observed in histologically normal bone or within the marrow. Our findings demonstrate directly the selective nature of accumulation and retention of 89Sr and confirm previous clinical impressions.
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PMID:Selective accumulation of strontium-89 in metastatic deposits in bone: radio-histological correlation. 754 2

Strontium-89 is preferentially taken up at sites of increased bone mineral turnover, its uptake adjacent to malignant metastases being up to five times greater than for normal bone. Strontium-89 is also selectively retained in bone adjacent to metastatic sites. The initial therapeutic ratio is therefore good and increases with time. The pharmacokinetics of strontium-89 thus favor the objective of achieving a clinically effective beta radiation dose to tumor deposits while minimizing radiation exposure to healthy tissue. Clinical studies show that 150 MBq [corrected] strontium-89 can relieve bone pain in up to 80% of patients with prostatic metastases. Greater activities do not appear to increase this level of response. Once a response has been achieved, strontium-89 therapy can be repeated when pain recurs. Although hematologic toxicity at this dosage is low, strontium-89 should not be given to patients with evidence of significant bone marrow depression. With this precaution, no serious toxicity has been encountered when the agent is administered at the recommended doses.
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PMID:Radionuclide-targeted therapy for the management of metastatic bone pain. 768 62

Reports published in the English literature of clinical trials utilizing intravenous strontium 89 (89Sr) in the treatment of patients with prostatic adenocarcinoma metastatic to bone were reviewed. Correlation coefficients were calculated for increasing dose of 89Sr and complete pain relief and complete and partial pain relief. Statistically significant positive correlations were obtained for complete relief of pain. Positive correlations were also found between those patients who had at least partial pain relief (defined as at least a 50% reduction in analgesia requirement), but these did not reach significance. This analysis suggests that a dose response relationship may exist between the dosage of 89Sr administered, and complete relief of pain due to skeletal metastases. The optimal dosage of 89Sr in this clinical situation has not been established, and prospective, carefully executed and analyzed randomized trials will be required to test whether and to what extent dose intensity of 89Sr determines outcome independently of other factors.
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PMID:Strontium 89 therapy and relief of pain in patients with prostatic carcinoma metastatic to bone: a dose response relationship? 768 18

New advances in systemic radionuclide therapy have increased the number of treatment options available for patients with painful osseous metastases. This form of therapy has three major appeals: 1) it addresses all sites of involvement; 2) selective absorption into bone limits irradiation of normal tissues; and 3) as a result, toxicity may be reduced and the therapeutic ratio improved. The clinical experience with radioactive phosphorus, strontium, samarium, and rhenium are reviewed. To date, the best studied and the only Food and Drug Administration approved agent is strontium-89. About 60% to 90% of patients treated with strontium-89 respond with complete or partial relief of pain for a median duration of 6 months. Large, prospectively randomized clinical trials have established the efficacy of strontium-89 as a first-line therapy and as an adjuvant to external-beam radiotherapy. Particularly advantageous is its usefulness in situations in which external-beam radiotherapy options have been exhausted and normal tissue tolerance has been reached. Newer radiopharmaceuticals are still under investigation.
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PMID:Systemic administration of new therapeutic radioisotopes, including phosphorus, strontium, samarium, and rhenium. 782 73


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