RESUMEN
On May 15, 2013, Bayer Healthcare Pharmaceuticals announced that it had received marketing approval for the therapeutic radioactive medication radium Ra 223 dichloride injection (Xofigo; Ra 223). The product acquisition and distribution process for hospital-based nuclear pharmacies and nuclear medicine services is unlike any other. The product is distributed as a low-risk compounded sterile preparation through a single compounding nuclear pharmacy located in Denver, Colorado, pursuant to a prescription. This model for drug distribution and delivery to the user institution has implications for product quality, patient privacy, and delineation of professional responsibilities.
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Radiofármacos , Radio (Elemento) , Confidencialidad , Humanos , Inyecciones , Servicio de Farmacia en Hospital , RadioisótoposRESUMEN
BACKGROUND: Poor results for dual-phase parathyroid scintigraphy have recently prompted increased use of dual-tracer imaging. We noticed that seminal studies used higher radiochemical purity than provided by current commercial preparations meeting US Pharmacopea (USP) specifications (90% of technetium bound to sestamibi). We surmised that the presence of unbound Tc (non-MIBI tracer) might hamper dual-phase detection that is dependent on rapid wash-out of technetium from thyroid tissue. PURPOSE: To test the hypothesis that reducing non-MIBI tracer will enhance thyroid wash-out and improve sensitivity of dual-phase imaging. METHODS: Starting in April 2003 we decreased the technetium to sestamibi ratio. This resulted in a significant decrease of non-MIBI tracer from 8.1+/-2.2% (SD) (group 1, n = 42) to 3.5+/-1.1% (group 2, n = 47) (P < 0.05 t-test). We performed a retrospective review of 89 patients with primary hyperparathyroidism who underwent imaging and subsequent surgery. The pathological findings served as the 'gold standard'. RESULTS: Scanning detected 21/39 diseased glands (sensitivity=54%) in group 1 patients. In group 2 imaging detected 38/45 diseased glands (sensitivity = 84%). An improvement in sensitivity (P < 0.01) was achieved by modifying the radiopharmaceutical preparation. CONCLUSIONS: Elevated levels of non-MIBI tracer in Tc-MIBI commercial preparations result in persistent thyroid background activity that may interfere with detection of parathyroid pathology. Achieving a higher degree of radiochemical purity (at least 95% bound, 5% impurities) than required by USP may be needed for optimal results. The large variation in sensitivity reported in the literature may be related in part to non-uniform radiopharmaceutical preparation.
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Enfermedades de las Paratiroides/diagnóstico , Neoplasias de las Paratiroides/diagnóstico por imagen , Neoplasias de las Paratiroides/diagnóstico , Cintigrafía/métodos , Tecnecio Tc 99m Sestamibi/análisis , Adulto , Anciano , Industria Farmacéutica , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Radiofármacos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
As an alternative method of oral administration of (131)I to a patient with quadriplegia and severe swallowing difficulties, we introduced, into the back of the patient's mouth, a 200- micro L laboratory pipette containing 74 MBq (2 mCi) of (131)I-sodium iodide in a 76- micro L aqueous solution and delivered its contents. The procedure was repeated a few days later with a 1,000- micro L laboratory pipette to administer 1.48 GBq (40 mCi) of (131)I-sodium iodide in a 270- micro L aqueous solution. The patient tolerated both procedures well. The pipette permitted accurate measurement of both dosages and complete (greater than 99.9%) delivery of the tracer in a small volume to the back of the patient's mouth, as documented by assay of the empty pipette after use. In patients with swallowing difficulties, use of the pipette constitutes a safe and efficient means to deliver (131)I-sodium iodide by the oral route.