A Critical Assessment of the Linear No-Threshold Hypothesis: Its Validity and Applicability for Use in Risk Assessment and Radiation Protection.

The Society of Nuclear Medicine and Molecular Imaging convened a task group to examine the evidence for the risk of carcinogenesis from low-dose radiation exposure and to assess evidence in the scientific literature related to the overall validity of the linear no-threshold (LNT) hypothesis and its applicability for use in risk assessment and radiation protection. In the low-dose and dose-rate region, the group concluded that the LNT hypothesis is invalid as it is not supported by the available scientific evidence and, instead, is actually refuted by published epidemiology and radiation biology. The task group concluded that the evidence does not support the use of LNT either for risk assessment or radiation protection in the low-dose and dose-rate region.

The AEC/NRC 30 mCi rule: regulatory origins and clinical consequences for 131I remnant ablative doses.

Background: Clinical and historical uncertainty exists surrounding the regulations of the Atomic Energy Commission/Nuclear Regulatory Commission (AEC/NRC) requiring patient hospitalization when (131)I activities exceed 30 mCi. This review investigates the sometimes disturbing regulatory and clinical origins and consequences of the use of this low, 30 mCi dose as a prescription for thyroid remnant ablation.

Summary: As early as in the 1940s, activities of (131)I between 30 and 200 mCi, often fractionated, were employed.

Prevalence of adverse events to radiopharmaceuticals from 2007 to 2011.

Unlabelled: We studied the changing patterns of radiopharmaceutical use and the incidence of adverse events (AEs) to PET radiopharmaceuticals, non-PET radiopharmaceuticals, and adjunctive nonradioactive pharmaceuticals in nuclear medicine from 2007 to 2011.

Methods: Fifteen academic institutions submitted quarterly reports of radiopharmaceutical use and AEs covering 2007-2011.

Results: 1,024,177 radiopharmaceutical administrations were monitored: 207,281 diagnostic PET, 803,696 diagnostic non-PET, and 13,200 therapeutic.

Radioiodine: the classic theranostic agent.

Radioiodine has the distinction of being the first theranostic agent in our armamentarium. Millennia were required to discover that the agent in orally administered seaweed and its extracts, which had been shown to cure neck swelling due to thyromegaly, was iodine, first demonstrated to be a new element in 1813. Treatment of goiter with iodine began at once, but its prophylactic value to prevent a common form of goiter took another century.

The problem of the patient with thyroglobulin elevation but negative iodine scintigraphy: the TENIS syndrome.

The available data upon which to act in caring for patients with functioning thyroid cancer and thyroglobulin elevation/negative iodine scintigraphy (TENIS) are imperfect, almost never coming from randomized, blinded studies. When the serum thyroglobulin exceeds 2-10 ng/mL, one should use the latest imaging equipment available to find metastatic disease, especially in areas in which it is potentially resectable, ie, neck, bone, and occasionally brain, and collaborate with an experienced surgeon in removing such metastases. If one cannot locate operable metastases and/or tumor location remains elusive, empiric high-dose (131)I therapy, preceded by dosimetry, should be considered.

Therapeutic guidelines for the treatment of bone metastasis: a report from the American College of Radiology Appropriateness Criteria Expert Panel on Radiation Oncology.

Bone metastases remain a therapeutic challenge because of the diversity of the problems they cause, the relative paucity of data regarding their treatment, and the necessity for management by a multidisciplinary palliative care team. The American College of Radiology convened an Appropriateness Criteria Expert Panel on Radiation Oncology for the treatment of bone metastasis to create representative clinical case scenarios and then rank the appropriate use of treatment modalities as well as the most reasonable radiotherapy dose schema and treatment planning methods. Here we present both the resulting Appropriateness Criteria and the rationale for making these decisions.

Reducing the incidence of 131I-induced sialadenitis: the role of pilocarpine.

Unlabelled: The goal of this study was to reduce the salivary symptoms of pain and xerostomia caused by 131I therapy for papillary and follicular thyroid carcinoma.

Methods: In a single-blind controlled prospective study of 60 patients, we investigated whether pilocarpine, 5 mg orally every 8 h for 1 wk after 131I therapy, would reduce salivary symptoms. All patients received 8 mg of dexamethasone and 100 mg of dolasetron mesylate orally 2 h before therapy and every 12 h for another 5 doses after 131I ingestion.

Comparison of outcomes after (123)I versus (131)I pre-ablation imaging before radioiodine ablation in differentiated thyroid carcinoma.

Unlabelled: Detection of residual tissue after thyroidectomy for papillary or follicular thyroid carcinoma may be performed using diagnostic imaging with either (123)I or (131)I. The former is often preferred to avoid "stunning"-defined as a reduction in uptake of the therapeutic dose of (131)I caused by some form of cell damage from the diagnostic dosage of the radionuclide. Stunning could potentially reduce the therapeutic efficacy of (131)I given to ablate a post-thyroidectomy remnant.

Bone mineral density (BMD) assessment of central skeletal sites from peripheral BMD and ultrasonographic measurements: an improved solution employing age and weight in type 3 regression.

The objective of this study was to develop a method whereby bone mineral density measurements of the heel and finger, as well as ultrasonographic measurements of calcaneal sound transmission, could identify individuals with a diagnosis of osteoporosis or osteopenia by the World Health Organization criteria for these diagnoses in the central skeleton (i.e., the lumbar spine (LS) and hip [femoral neck] [FN]).

The US national isotope program: current status and strategy for future success.

Since their introduction in the 1940s, peaceful use of stable isotopes and radioisotopes in the United States has expanded continuously. Today, new isotopes for diagnostic and therapeutic uses are not being developed, critical isotopes for national security are in short supply, and demand for isotopes critical to homeland security exceeds supply. While commercial suppliers, both domestic and foreign, can only meet specific needs, the nation needs a consistent, reliable supply of radioactive and stable isotopes for research, medical, security, and space power applications.

Teletherapy and radiopharmaceutical therapy of painful bone metastases.

Bone pain from metastatic disease is most common in cancers of the breast, prostate, and lung. Despite the World Health organization algorithm for treating such pain, the outcomes are not often satisfactory. In 2005, there will be 3 radiopharmaceuticals available in the United States that can reduce or relieve bone pain caused by osteoblastic metastases with apparently equal efficacy.