On specificity of 2nd generation TSH receptor autoantibody measurements.

Background: TSH receptor (TSHR) antibodies (TRAb) are the hallmark in the serological diagnosis of Graves' disease (autoimmune hyperthyroidism). Irrespective of receptor origin second generation TRAb assays have been shown to be more sensitive than original first generation assays. The specificity of both assay generations is claimed to be close to 100% for discriminating healthy individuals from Graves' disease patients.

[Influence of time-dose-relationships in therapeutic nuclear medicine applications on biological effectiveness of irradiation: consequences for dosimetry].

Aim: The biological effectiveness of irradiation is influenced not only by the total dose but also the rate at which this dose is administered. Tolerance dose estimates from external radiation therapy with a conventional fractionation protocol require adaptation for application in targeted radionuclide therapy.

Methods: The linear-quadratic model allows for calculation of the biologically effective dose (BED) and takes into consideration tissue specific factors (recovery capacity) as well as dose rate effects (recovery kinetics).

Radiation treatment planning in brain tumours: potential impact of 3-O-methyl-6-[(18)F]fluoro-L-DOPA and PET.

Aim: Amino acid PET has become an important diagnostic tool for brain tumour imaging. In this data analysis, the potential impact of amino acid PET with 3-O-methyl-6-[(18)F]fluoro-L-DOPA ([(18)F]OMFD) on radiation treatment planning is addressed by the following questions: 1. Was tumour tissue identified with OMFD-PET which was not covered by the conventionally derived planning target volume (PTV)? 2.

A semi-automated system for concentration of rhenium-188 for radiopharmaceutical applications.

A semi-automated system has been designed and installed for the routine production of highly concentrated solutions of rhenium-188 perrhenate in saline which incorporates extensive radiation protection for the laboratory staff. This new system represents a simple, rapid, and effective computer controlled method using inexpensive disposable components. The flipper-valve settings and the radioactivity measured by use of collimated gamma dose rate probes are continuously monitored.

Additional PET/CT in week 5-6 of radiotherapy for patients with stage III non-small cell lung cancer as a means of dose escalation planning?

Background And Purpose: Loco-regional failure after radiotherapy with total doses of 60-70 Gy for non-small cell lung cancer (NSCLC) remains a major clinical problem. Escalation of radiation dose is often limited because of exceeding normal tissue constraints. The present study was designed to test the hypothesis that a reduction in disease volume during radiotherapy detected by FDG PET/CT would facilitate radiation dose escalation, whilst remaining within normal tissue constraints.

Are porcine and human TSH receptor antibody measurements comparable?

Background: The human TSH receptor antibody (TRAb) assay is reported to show higher sensitivity in comparison to the "classical" porcine TRAb testing. This claim is based on studies comparing porcine TSH receptor (TSH-R) in one type of assay system (non-immobilized TSH-R and PEG to separate bound and free) with recombinant human TSH-R in another type of assay system (TSH-R immobilized on plastic tubes). In this study isotopic TRAb assays both based on the "coated tube" system (second generation) were compared for the first time.

Current progress and future challenges in the biochemical diagnosis and treatment of pheochromocytomas and paragangliomas.

Findings from five independent studies - with close to 350 patients with pheochromocytoma and more than 2,500 in whom the tumor was excluded - indicate that measurements of plasma free metanephrines provide an overall diagnostic sensitivity of 98% and specificity of 92%. The recommendation that initial testing for the tumor should always include measurements of either plasma or urinary fractionated metanephrines results from recognition of the high diagnostic sensitivity of measurements of plasma metanephrines. The few patients with pheochromocytoma in whom the test may not yield a positive result include those with very small tumors or microscopic disease and others with tumors that do not produce norepinephrine and epinephrine.

[18F]-FDG-PET in clinical stage I/II non-seminomatous germ cell tumours: results of the German multicentre trial.

Purpose: The aim of this study was to determine the predictive values of 2-[fluorine-18]fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) in primary staging in patients with newly diagnosed non-seminomatous germ cell tumour (NSGCT) clinical stage I/II.

Patients And Methods: The hypothesis was that FDG-PET would improve the negative predictive value (NPV) from 70% to 90%, thus requiring a total of 169 patients. All scans underwent visual analysis by a reference team of nuclear medicine physicians.

Feasibility of high activity rhenium-188-microsphere in hepatic radioembolization.

Background: This paper describes the feasibility of intra-arterial high-activity administration of (188)Re-microspheres.

Methods: Patients with unresectable colorectal liver metastases or hepatocellular cancer (HCC) received single treatments with (188)Re-microspheres. The administered activity was calculated to give a liver dose of 100 Gy.

[FDG-PET/CT in oncology. German Guideline].

FDG-PET/CT examinations combine metabolic and morphologic imaging within an integrated procedure. Over the past decade PET/CT imaging has gained wide clinical acceptance in the field of oncology. This FDG-PET/CT guideline focuses on indications, data acquisition and processing as well as documentation of FDG-PET/CT examinations in oncologic patients within a clinical and social context specific to Germany.

Very stable 188Re-S4 chelates for labelling biomolecules: preparation with highly concentrated perrhenate eluates.

Aim: The preparation and stability of a new (188)Re-S(4)-complex [S(4) = (1-aza-18-crown-6)(O)C-C(SH)-C(SH)-C(O)NH-(CH(2))(3)-NH-(CH(2))(3)-NHC(O)-C(SH)-C(SH)-C(O)(1-aza-18-crown-6] was studied at therapeutic relevant radioactive concentrations. The results were compared with (188)Re-MAG(3) (MAG(3): mercaptoacetyltriglycine) and (188)Re-DMSA preparations (DMSA: dimercaptosuccinic acid) performed with the same highly concentrated [(188)Re]perrhenate solution (12-15 GBq/ml).

Methods: The (188)Re complexes were prepared by direct reduction of perrhenate ((188)Re-S(4)-complex) as well as via the (188)Re-EDTA precursor complex ((188)Re-MAG(3), (188)Re-DMSA).

The floating Meckel.

A 10-year-old girl was hospitalized because of abdominal pain and significant gastrointestinal bleeding for 3 days with hematocrit of 28% and hemoglobin of 6.1 mmol/L. Gastroscopy and abdominal ultrasound did not reveal any gastrointestinal abnormalities and parameters of coagulation were normal.

A comparative study of 188Re-HEDP, 186Re-HEDP, 153Sm-EDTMP and 89Sr in the treatment of painful skeletal metastases.

Aim: The surface bone-seeking radiopharmaceuticals 188Re-HEDP, 186Re-HEDP and 153Sm-EDTMP, and the volume seeker 89Sr were investigated to determine the efficacy and toxicity in pain palliation of bone metastases.

Method: The effect of treatment with 188Re-HEDP, 186Re-HEDP, 153Sm-EDTMP and 89Sr on pain symptoms, quality of life, and bone marrow function were studied. In total, 79 patients (18 with breast cancer and 61 with prostate cancer) were treated (31 patients with 188Re-HEDP, 15 patients each with 186Re-HEDP and 153Sm-EDTMP, and 18 patients with 89Sr).

Effect of increase of radiation dose on local control relates to pre-treatment FDG uptake in FaDu tumours in nude mice.

Objectives: To investigate whether heterogeneity in [(18)F]2-fluoro-2-deoxy-d-glucose (FDG) uptake in a single tumour line, i.e. in tumours with identical genetic background, relates to radiation response.

Diagnostic impact of PET with 18F-FDG, 18F-DOPA and 3-O-methyl-6-[18F]fluoro-DOPA in recurrent or metastatic medullary thyroid carcinoma.

Purpose: In patients with medullary thyroid carcinoma (MTC), rising levels of the tumour markers calcitonin and CEA after primary surgery indicate tumour recurrence or metastases. The only chance of cure is the resection of localised tumour tissue. For positron emission tomography (PET) with (18)F-fluorodeoxyglucose ((18)F-FDG) and (18)F-dihydroxyphenylalanine ((18)F-DOPA), sensitivities of 78% and 63% have been reported, but in a considerable percentage of MTC patients the source of tumour marker elevation is not detected.

[1-(11)C]acetate uptake is not increased in renal cell carcinoma.

Purpose: The purpose of this study was to investigate the potential of [1-(11)C]acetate (AC) as a metabolic tracer for renal cell cancer in human subjects.

Methods: Twenty-one patients with suspected kidney tumours were investigated with AC and dynamic PET. AC uptake was scored on a five-step scale.

Impact of staging with 18F-FDG-PET on outcome of patients with stage III non-small cell lung cancer: PET identifies potential survivors.

Purpose: The aim of this study was to analyse the impact of FDG-PET staging on treatment results of neo-adjuvant radiochemotherapy in patients with advanced non-small cell lung cancer (NSCLC). We compared prospectively the outcome of two patient groups with stage III NSCLC undergoing the same neo-adjuvant radio-chemotherapy (NARCT). In one group, FDG-PET was part of the pretherapeutic staging, whereas in the other group, no PET scans were performed.

Intracoronary beta-brachytherapy using a rhenium-188 filled balloon catheter in restenotic lesions of native coronary arteries and venous bypass grafts.

Purpose: We have previously demonstrated the efficacy of intracoronary beta-brachytherapy using a liquid (188)Re-filled balloon in a randomised trial including de novo lesions. Percutaneous coronary interventions in restenotic lesions and in stenoses of venous bypass grafts are characterised by a high recurrence rate for restenosis and re-interventions. Against this background, we wanted to assess the impact of intracoronary beta-brachytherapy using a liquid (188)Re-filled balloon in restenotic lesions in native coronary arteries and venous bypass grafts.

[Positron emission tomography (PET) in oncology: a part of medical therapeutic expertise].

Early inclusion of positron emission tomography (PET) in the stepwise oncological diagnosis improves tumor staging and can make further costly diagnostic and inadequate therapeutic measures superfluous. The advantage of this method, in answering the many questions that arise, has been supported by an extensive literature and analysis of interdisciplinary data. Its use is therefore demanded by doctors working in oncology.