Processing of generator-produced 68Ga for medical application.

Unlabelled: The (68)Ge/(68)Ga generator provides an excellent source of positron-emitting (68)Ga. However, newly available "ionic" (68)Ge/(68)Ga radionuclide generators are not necessarily optimized for the synthesis of (68)Ga-labeled radiopharmaceuticals. The eluates have rather large volumes, a high concentration of H(+) (pH of 1), a breakthrough of (68)Ge, increasing with time or frequency of use, and impurities such as stable Zn(II) generated by the decay of (68)Ga, Ti(IV) as a constituent of the column material, and Fe(III) as a general impurity.

[Significance of PET and integrated PET/CT in the diagnostics of occult primary tumors].

Background: In the last years (18)F-FDG-positron-emission-tomography (PET) worked satisfactorily as helpful auxiliary method in order to verify recurrency of head and neck tumors and to detect primary tumors in case of CUP syndrome especially when CT and MR imaging failed to identify the tumor accurately. Fusion of FDG hypermetabolism in PET scan and anatomical structures is achieved by integrating positron emission tomography with CT and provides improvement also in case of CUP syndrome. This retrospective study shows 47 patients with neck metastases where PET or PET/CT helped to detect primary tumor site.

[The integrated PET/CT: technological advance in diagnostics of head and neck recurrencies and CUP?].

Background: In the last years (18)F-Fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) worked satisfactorily as auxiliary method in order to show recurrency of head and neck tumors and to detect primary tumors in case of CUP especially when CT and MR imaging failed to identify the tumor accurately. The correlation of FDG hypermetabolism and anatomical structures is now provided by a new technology which is integrating PET and CT: Integrated PET/CT represents a new technical development, which combines the advantages of CT and PET.

Patients: In a retrospective investigation 84 non selected PET/CT studies of 83 patients with recurrent head and neck disease and CUP were critically analyzed.

Positron emission tomography with [(18)F]FDG in the diagnosis of Creutzfeldt-Jakob disease (CJD).

The aim of this study was to explore the sites of metabolic changes with [(18)F]2-fluoro-2-desoxy-D-glucose (FDG) and positron emission tomography (PET) in patients with Creutzfeldt-Jakob disease and to correlate the findings with clinical symptoms. Static [(18)F]FDG-PET studies of eight patients with the diagnosis of confirmed or probable CJD were retrospectively analysed by two physicians from departments of nuclear medicine independently with a strong interrater agreement (kappa=0,98). The clinical data of the patients, based on a standardized evaluation by physicians from the German Creutzfeldt-Jakob disease surveillance study, was correlated with the PET findings.

131 I-cG250 monoclonal antibody immunoscintigraphy versus [18 F]FDG-PET imaging in patients with metastatic renal cell carcinoma: a comparative study.

The aims of this study were to establish the percentage of metastatic renal cell carcinoma (RCC) lesions detected by radioimmunoscintigraphy (RIS) with the chimeric monoclonal antibody 131I-cG250 versus positron emission tomography (PET) with 18F-labelled deoxyglucose ([18F]FDG), and to evaluate the use of these radionuclide imaging modalities compared with routinely used imaging techniques. Twenty patients with metastatic RCC disease were examined with [18F]FDG-PET and 131I-cG250 RIS within 1 week. Total body gamma camera images were obtained up to 120h after injection of 232MBq 131I-cG250.

[Radiosynovectomy for the treatment of rheumatoid arthritis of the elbow joint].

Unlabelled: The aim of this retrospective study was to evaluate the efficacy of radiosynovectomy (RSO) in patients with rheumatoid elbow arthritis.

Patients And Methods: 40 joints of 31 patients were evaluated. At the time of therapy, patients had been suffering from elbow arthritis for 17.

Absence of somatostatin receptor expression in vivo is correlated to di- or tetraploid 1p36-deleted neuroblastomas.

Background: Poor prognosis in childhood neuroblastoma is associated with deletions of chromosome region 1p36 and di/tetraploid DNA content.

Procedure: Forty-six patients with histopathologically proven neuroblastoma were investigated for in vivo expression of somatostatin receptors (SR) by 111In-pentetreotide scintigraphy. All tumors were analyzed for cytometric DNA content and chromosome 1p36 integrity.

Clinical relevance of positron emission tomography (PET) in treatment control and relapse of Hodgkin's disease.

Background: In Hodgkin's disease accurate restaging is important to assess treatment results and may eventually provide a basis for further therapeutic strategies. A typical dilemma after treatment of Hodgkin's disease with radiographically persistent lymphoma is the differentiation between sterilized residual mass and viable tumor. Positron emission tomography (PET) has been described as a reliable tool to identify active lymphoma.

Whole body positron emission tomography in the treatment of Hodgkin disease.

Background: In Hodgkin disease (HD), accurate assessment of the extent of disease is essential because it provides the basis for different treatment strategies. In addition to conventional imaging methods (CIM), positron emission tomography with fluorine-18-fluorodeoxyglucose (FDG-PET) may permit reliable differentiation between lymphoma and nonmalignant tissue and thus improve determination of the stage of the disease. The aim of the current study was to assess the clinical value of FDG-PET for primary staging, treatment monitoring, and assessment in a suspected case of recurrent HD.

Combined (111)In-pentetreotide scintigraphy and (123)I-mIBG scintigraphy in neuroblastoma provides prognostic information.

Background: High-affinity somatostatin receptors (SRs) have been characterized in neuroblastomas and may be used as target structures for in vivo detection of SR.

Procedure: Eighty-eight children with histologically proven neuroblastoma were investigated at diagnosis or relapse by (123)I-mIBG and (111)In-pentetreotide scintigraphy. All tumors were investigated for MYCN copy number, chromosome 1p36 status, and 68/88 also for DNA content, followed for a median follow-up of 35 months (range 1-88 months).

Somatostatin in neuroblastoma and ganglioneuroma.

Neuroblastoma, a childhood tumour of the sympathetic nervous system, may in some cases differentiate to a benign ganglioneuroma or regress due to apoptosis. Somatostatin may inhibit neuroblastoma growth and induce apoptosis in vitro and was therefore investigated. Using a radioimmunoassay, we found that all ganglioneuromas contained high somatostatin concentrations (> 16 pmol/g), significantly higher than neuroblastomas (n = 117, median 2.

Comparison of MIBG and pentetreotide scintigraphy in children with neuroblastoma. Is the expression of somatostatin receptors a prognostic factor?

Background: Neuroblastoma (NB) is the fourth most common pediatric malignancy and recent reports suggest a prognostic role of somatostatin receptor scintigraphy (SRS) in this disease.

Materials And Methods: Twenty two patients (pts. mean age 43.

Technetium-99m human immunoglobulin (HIG): a new substance for scintigraphic detection of bone and joint infections.

Technetium (99m-Tc)-labelled, polyclonal human immunoglobulin (HIG) has been described as a new agent to detect local infection and inflammation. In this study, we tested 99m-Tc HIG in 55 patients with suspected chronic (n = 42) and acute (n = 13) skeletal infection. Diagnosis was proven operatively (n = 44) and clinically (n = 11), including microbiological culture tests (n = 46).

[Value of 99mTc-MIBI scintigraphy in diagnostic localization of hyperparathyroidism. A prospective study].

We evaluated the sensitivity of praeoperative parathyroid imaging using 99mTc-MIBI scintigraphy in planar as well as SPECT technique to detect and localize abnormal parathyroid glands in 36 patients with hyperparathyroidism. Seven out of these patients had been previously operated in the thyroid area. With a sensitivity of 76% (22/29) solid adenomas could be localized correctly.

Efficient symptomatic control of carcinoid tumors with somatostatin in patients with disease progression under alpha-interferon therapy.

Background/aims: We report--as a retrospective observation--on eight patients with malignant carcinoid tumors.

Materials And Methods: All patients were initially treated with alpha-interferon and received the longacting somatostatin analogue octreotide (SMS 201-995) after disease progression. Tumor growth was monitored by CT-scan or ultrasound.

Somatostatin receptor imaging in persistent medullary thyroid carcinoma.

Objective: Somatostatin is secreted from thyroid C-cells and seems to play an important part in the regulation of calcitonin secretion. We therefore evaluated the usefulness of somatostatin receptor scintigraphy in the localization of tumour tissue in patients with persistent medullary thyroid carcinoma.

Design: A prospective clinical study.

Radioimmunotherapy with monoclonal antibodies. A new horizon in nuclear medicine therapy?

Radioimmunotherapy (RIT) with labeled tumor-associated monoclonal antibodies (MAbs) is a promising concept in oncology, which essentially consists of biological targeting of ionising radiation to tumors. Some encouraging clinical results have been achieved with RIT. However, there are severe problems associated with both understanding the mechanisms and predicting the effectiveness of RIT.