Positron emission tomography (PET) and other nuclear medicine modalities in staging gastrointestinal cancer

Abstract Introduction Nuclear medicine parathyroid imaging is important in the identification of hyperfunctioning parathyroid glands in primary hyperparathyroidism (pHPT), but it may be also valuable before surgical treatment in secondary hyperparathyroidism (sHPT). Parathyroid radionuclide imaging with scintigraphy or positron emission tomography (PET) is a highly sensitive procedure for the assessment of the presence and number of hyperfunctioning parathyroid glands, located either at typical sites or ectopically. The treatment of pHPT is mostly directed toward minimally invasive parathyroidectomy, especially in cases with a single adenoma. In experienced hands, successful surgery depends mainly on the exact preoperative localization of one or more hyperfunctioning parathyroid adenomas. Failure to preoperatively identify the hyperfunctioning parathyroid gland challenges minimally invasive parathyroidectomy and might require bilateral open neck exploration. Methods Over a decade has now passed since the European Association of Nuclear Medicine (EANM) issued the first edition of the guideline on parathyroid imaging, and a number of new insights and techniques have been developed since. The aim of the present document is to provide state-of-the-art guidelines for nuclear medicine physicians performing parathyroid scintigraphy, single-photon emission computed tomography/computed tomography (SPECT/CT), positron emission tomography/computed tomography (PET/CT), and positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with pHPT, as well as in those with sHPT. Conclusion These guidelines are written and authorized by the EANM to promote optimal parathyroid imaging. They will assist nuclear medicine physicians in the detection and correct localization of hyperfunctioning parathyroid lesions.

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Automated Light-Induced Synthesis of 89Zr-Radiolabeled Antibodies for Immuno-Positron Emission Tomography

10.21203/rs.3.rs-941904/v1 ◽

2021 ◽

Author(s):

Simon Klingler ◽

Jason Holland

Keyword(s):

Positron Emission Tomography ◽

Nuclear Medicine ◽

Radiochemical Yield ◽

Emission Tomography ◽

Desferrioxamine B ◽

Automated Method ◽

Isolation And Characterization ◽

Positron Emission ◽

The Many ◽

Radiolabeled Antibodies

Abstract Clinical production of 89Zr-radiolabeled antibodies (89Zr-mAbs) for positron emission tomography (PET) imaging relies on the pre-conjugation of desferrioxamine B (DFO) to the purified protein, followed by isolation and characterization of the functionalized intermediate, and then manual radiosynthesis. Although highly successful, this route exposes radiochemists to a potentially large radiation dose and entails several technological and economic hurdles that limit access of 89Zr-mAbs to just a specialist few Nuclear Medicine facilities worldwide. Here, we introduce a fully automated synthesis box that can produce individual doses of 89Zr-mAbs formulated in sterile solution in <25 min starting from [89Zr(C2O4)4]4– (89Zr-oxalate), our Good Laboratory Practice-compliant photoactivatable desferrioxamine-based chelate (DFO-PEG3-ArN3), and clinical-grade antibodies without the need for pre-purification of protein. The automated steps include neutralization of the 89Zr-oxalate stock, chelate radiolabeling, and light-induced protein conjugation, followed by 89Zr-mAb purification, formulation, and sterile filtration. As proof-of-principle, 89ZrDFO-PEG3-azepin-trastuzumab was synthesized directly from Herceptin in <25 min with an overall decay-corrected radiochemical yield of 20.1±2.4% (n=3), a radiochemical purity >99%, and chemical purity >99%. The synthesis unit can also produce 89Zr-mAbs via the conventional radiolabeling routes from pre-functionalized DFO-mAbs that are currently used in the clinic. This automated method will improve access to state-of-the-art 89Zr-mAbs at the many Nuclear Medicine and research institutions that require automated devices for radiotracer production.

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Polymyalgia rheumatica in the 2018–2020 guidelines. Part II: diagnosis of vasculitis

PAIN JOINTS SPINE ◽

10.22141/2224-1507.11.1.2021.226904 ◽

2021 ◽

Vol 11 (1) ◽

pp. 1-16

Author(s):

О.H. Puzanova ◽

А.А. Lyzikov

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Nuclear Medicine ◽

Giant Cell Arteritis ◽

Giant Cell ◽

Computed Tomography Angiography ◽

Polymyalgia Rheumatica ◽

Aortic Aneurysms ◽

Emission Tomography ◽

Positron Emission

The issue of improved diagnosis of both rheumatic diseases of the elderly and aortic diseases does not lose its relevance. In terms of aortic aneurysms, dissection and ruptures and their attended pathogenesis, both inflammation and structural wall damages may be detected with imaging methods whose role is vital. A number of international guidelines deal with the management of polymyalgia rheumatica, giant cell arteritis, or aortic aneurysms. Aortitis is associated with up to 40 % of polymyalgia rheumatica’s cases. The clinical suspicion of aortitis is based on the detection of blood pressure and pulse asymmetry, aortic regurgitation murmur, vascular bruits, as well as persistent polymyalgia rheumatica or inflammatory dorsalgia, pelvis or leg pain. In 2020, the positron emission tomography/computed tomography’s use is approved by the Italian Society for Rheumatology for the diagnosis of vasculitis attended by polymyalgia rheumatica at the secondary healthcare level and by the European Headache Federation for the diagnosis of large vessel giant cell arteritis in the neurological practice. A review of the guideline by the European Association of Nuclear Medicine, the Society of Nuclear Medicine and Molecular Imaging, and the American Society of Nuclear Cardiology (2018) was performed in terms of positron emission tomography with fluorodesoxyglucose combined with computed tomography (angiography) imaging in large vessel vasculitis and polymyalgia rheumatica. It is further compared with the clinical guidelines, other guidelines by the societies of nuclear medicine and new scientific data. Both procedure and patient’s preparation for examination are decribed. The criteria for assessing vasculitis proposed for either clinical practice or clinical studies are considered, as well as the factors influencing the test results and their interpretation (such as atherosclerosis, diabetes, age, body mass index, glucemia’s and acute phase markers’ levels). The guideline substantiates the benefit of both positron emission tomography’s use and its combination with computed tomography to detect extracranial vasculitis, as well as the value of performing computed tomography-angiography at different stages of the disease. There is a need to strengthen evidence on both standard time of fluorodesoxyglucose exposure and the benefit of combining positron emission tomography with computed tomography-angiography, in particular for detection of vasculitis relapses. Finding a consensus for early test’s performing is needed, as well as its score standardization, ensuring reimbursement and implementation of new imaging techniques for the cranial vessels. In the future, the evidence-based approach to managing vasculitis will be supplemented by teranostics.

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Polymyalgia rheumatica in the 2018–2020 clinical guidelines. Part I. At-risk groups, adjuvant therapy

PAIN JOINTS SPINE ◽

10.22141/2224-1507.10.4.2020.220456 ◽

2020 ◽

Vol 10 (4) ◽

pp. 161-173

Author(s):

О.G. Puzanovа

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Nuclear Medicine ◽

Adjuvant Therapy ◽

Giant Cell Arteritis ◽

Giant Cell ◽

Polymyalgia Rheumatica ◽

Emission Tomography ◽

Evidence Based ◽

Positron Emission

At the beginning of the Healthy Ageing Decade, a number of guidelines were published describing management of the rheumatic diseases of the elderly. The aim of the paper is to characterize and discuss the Italian Society of Rheumatology’s guideline for polymyalgia rheumatica (2020) and the European Association of Nuclear Medicine, the Society of Nuclear Medicine and Molecular Imaging, and the American Society of Nuclear Cardiology’s (2018) recommendation for positron-emission tomography/computed tomography imaging to diagnose the large vessel vasculitis and polymyalgia rheumatica. The following methods were used: original texts of recommedations, their content and methodology behind the development of both guidelines were studied by means of information analysis and compared with the recommendations for the management of polymyalgia rheumatica and giant cell arteritis elaborated in 2018–2020 by the European League Against Rheumatism, American College of Rheumatology; the German, Austrian, Swiss and British rheumatological societies; the European Headache Federation and their references. We’ve established the priority of consensus approach for the development of modern guidelines for polymyalgia rheumatica. The specific feature of the Italian guideline’s development is the search for prototypes restricted to the two evidence-based medicine databases and the grey literature as well as selection of three international guidelines for adaptation, one of them elaborated by the societies for nuclear medicine. The following issues were updated: the patient management in primary care (whose algorithm is proposed), including the conserted clinical decision-making and alertness to the giant cell arteritis. Out of the first-line therapy tools, only the initial doses of glucocorticoids are evidence-based, and their reduction is allowed as an alternating regimen. The ineffectiveness of hydroxichloroquine use is justified, while both azathioprine and alternative medical drugs are not subject to discussion. It is necessary to identify the risk factors for vasculitis and its relapses, longterm glucocorticoid use and their side effects. For the first time, the use of positron-emission tomography/computed tomography is recommended for detecting of vasculitis. The recommendation for adjuvant therapy with methotrexate and abstaining from the biologic agents is found the most evidence-based, strongest and consistent; referral to a rheumatologist being the least agreed-on position. Conclusion. Solving such an urgent healthcare problem as improving the quality of polymyalgia rheumatic management suggests the medical standards being raised on the most clinically important issues, the importance of at-risk patient identification and referral to rheumatologists and ophthalmologists, and consideration of the methotrexate’s benefits.

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