Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There is a long history recording the association of x radiation and the subsequent development of malignant tumors. For systematically administered isotopes this came into prominence when Martland discovered the association between cancer, particularly of the bone, and ingestion of radioactive isotopes by radium dial painters. This association was amplified by the development of cancer in patients given thorotrast as a contrast medium for diagnostic radiologic examination. Acute leukemia was reported 30 years ago in patients with polycythemia vera treated with 32P. Acute leukemia also occurs in patients with polycythemia vera treated only with phlebotomy or drugs. A controlled study is now underway to provide a more definite answer to question what is the incidence of acute leukemia in patients with polycythemia vera treated by phlebotomy alone, chlorambucil, or 32P. 131I for the treatment of hyperthyroidism probably does not induce cancer, but in the doses used for thyroid cancer there was an increased incidence of neoplasms (12/200 in one study). This was higher than the expected incidence of neoplasms. The doses of radioactive isotopes used currently for diagnostic purposes have not induced cancer, but it is difficult and probably impossible to verify this with absolute certainty.
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PMID:The association between systemically administered radioisotopes and subsequent malignant disease. 125 26

The diagnostic and therapeutic application of radionuclides in oncology has led to an increased efficiency in the treatment of malignant tumors. Regarding diagnosis, measuring metabolic reactions in tumor tissue, especially by positron emission tomography, opened the potential for assaying tumor response to different treatment modalities and thus eventually for tailoring effective treatment of a given tumor in the individual patient. Regarding treatment, attention is given to the choice of the radionuclide for optimal deposition of the desired radiation in tumor cells avoiding exposure of normal cells; in this context microdosimetric considerations are essential with respect to beta-emitters, alpha-emitters, the Auger-effect and neutron capture therapy. Examples of therapeutic uses of radionuclides in the inorganic form are 131-I for thyroid cancer and 32-P for polycythemia vera; organically bound radionuclides are employed with precursors for tumor cell metabolism or with receptor seeking agents, such as MIBG and monoclonal antibodies which presently enjoy a particular interest and bear great promise. Stable nuclides, if properly accumulated within tumors, may be activated for therapy in situ, for example by thermal neutrons, as in neutron capture therapy using the 10-B (n, alpha)7-Li reaction. Treatment planning and execution with radionuclides have gained momentum over the past decade, yet much more needs to be done.
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PMID:Contributions of nuclear medicine to the therapy of malignant tumors. 196 75

The therapeutic approach of internally administered radiopharmaceuticals offers the potential to outmode the present approaches of conventional radiation therapy and chemotherapy because of three characteristics: 1. The therapeutic use of radiopharmaceuticals may deliver as much as orders of magnitude larger rad doses than conventional radiation therapy to target tissues, selectively irradiating these tissues internally in one radiation dose. 2. The therapeutic use of radiopharmaceuticals is followed by a lower incidence of leukemia and other cancers. 3. The treatment is comparatively noninvasive and nontraumatic. We can now make this rather strong statement with fairly firm conviction because Na131I has been used since 1946 (33 years) to treat almost a million patients for hyperthyroidism (a) and in approximately 5000 patients for well-differentiated thyroid cancer (b); NaH2PO4(P-32) has been used for 35 years to treat approximately 25,000 patients with polycythemia vera (3-5).
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PMID:New horizons for therapeutic nuclear medicine in 1981. 722 26

Systemic unsealed radiation therapy is achieved when a radioactive substance is administered orally or parenterally and that material is concentrated in an organ or site for sufficient time to deliver a therapeutic dose of radiation. The radioactive material usually emits beta particles. In general, there is intense local radiation of the abnormal tissues, and normal organs, which do not trap the radioactive material, are exposed to a small radiation dose. The most frequent treatments involve radioiodine (131)I for hyperthyroidism and differentiated thyroid cancer. Other applications include treatment of painful skeletal metastases, polycythemia vera, malignant cysts, and neuroendocrine tumors. The treatments are usually well tolerated and not associated with long-term effects, such as cancer or infertility.
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PMID:Systemic radiation therapy with unsealed radionuclides. 1072 98

The therapeutic use of radioisotopes in medicine as unsealed sources has a long history dating back to the 1930s. The established and continuing objectives are to provide radiation dose to the target tissue at the desired cytotoxic level while avoiding or minimizing toxic effects. Selected radionuclide therapy protocols including 32P for polycythemia vera, 131I for Graves' disease, and 131I for postsurgical ablation of thyroid remnants in the management of differentiated thyroid cancer are presented for historical review with the focus on protocols for administering the radiopharmaceuticals and the role played by dosimetry. The discussion also includes consideration of complications and the assessment of outcome for these diseases. The vista for radionuclide therapy today is reviewed along with the options for determining the administered activity. Patient specific dosimetry encompasses a number of levels ranging from basic measurement of relevant biokinetic parameters and use of standard models to calculate (and extrapolate) radiation dose to sophisticated three-dimensional techniques employing fusion of physiologic and high-resolution anatomic images coupled with advanced 3-D voxel patient representation and Monte Carlo techniques for use in radiation dose calculation. The role of patient specific dosimetry in clinical trials (Phase I, II, III trials) along with its utility in treatment planning, follow-up evaluation, and elucidation of dose-response relationships is discussed. The challenge ahead for those who advocate patient specific dosimetry is to assemble the outcome data and perform the analysis to support this contention.
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PMID:Options for radionuclide therapy: from fixed activity to patient-specific treatment planning. 1191 75