EANM-EORTC general recommendations for sentinel node diagnostics in melanoma.

The accurate diagnosis of a sentinel node in melanoma includes a sequence of procedures from different medical specialities (nuclear medicine, surgery, oncology, and pathology). The items covered are presented in 11 sections and a reference list: (1) definition of a sentinel node, (2) clinical indications, (3) radiopharmaceuticals and activity injected, (4) dosimetry, (5) injection technique, (6) image acquisition and interpretation, (7) report and display, (8) use of dye, (9) gamma probe detection, (10) surgical techniques in sentinel node biopsy, and (11) pathological evaluation of melanoma-draining sentinel lymph nodes. If specific recommendations given cannot be based on evidence from original, scientific studies, referral is given to "general consensus" and similar expressions. The recommendations are designed to assist in the practice of referral to, performance, interpretation and reporting of all steps of the sentinel node procedure in the hope of setting state-of-the-art standards for good-quality evaluation of possible spread to the lymphatic system in intermediate-to-high risk melanoma without clinical signs of dissemination.

Influence of radiation source geometry on determination of (111)In and (90)Y activity of radiopharmaceuticals.

OBJECTIVE: Yttrium-90 (Y)-labelled peptides such as DOTATOC and antibodies such as Zevalin are widely used in radionuclide therapy. Indium-111 (In) is used as a Y surrogate for imaging and dosimetry purposes. We aimed to investigate accuracy, geometry (vials and syringes) and volume dependencies for both radionuclides in several different radionuclide calibrators. METHODS: YCl3 and InCl3 solutions were gravimetrically dispensed into the most frequently used containers. In each container several dilutions of the parent solutions were performed. Mass, activity and time were recorded for each calibrator and measurement. Aliquots of both parent solutions were calibrated at the National Metrology Laboratory, Vienna, Austria (BEV). From our measurements and results from BEV, correction factors were determined and further partitioned into calibration, geometry and volume correction factors. RESULTS: Using the nominal calibration factors provided by the manufacturer, measured activity in P6 vials was overestimated by up to 25% for In, depending on the calibrator. Y activity was either underestimated (by up to 20%) or overestimated (by up to 25%) using different radionuclide calibrators. This is the result of the difference in containers used to set the manufacturer's calibration factor values and the containers used in nuclear medicine departments and in this study. There was little geometry dependence for glass vials but strong geometry dependence for syringes for both radionuclides in all calibrators. CONCLUSION: The results should constitute a warning for all personnel responsible for preparation of radiopharmaceuticals. Every nuclear medicine department should incorporate a proper quality-control regimen for radionuclide calibrators and a quality-assurance system.

49A/G and CT60 polymorphisms of the cytotoxic T-lymphocyte-associated antigen 4 gene associated with autoimmune thyroid disease.

Single nucleotide polymorphisms in the CTLA-4 gene have been suggested as genetic factors in the susceptibility to autoimmune thyroid disease (AITD). In our case-control study, patients with Graves' disease, Hashimoto's thyroiditis, and postpartum thyroiditis and control subjects have been genotyped for two A/G single nucleotide polymorphisms (49A/G and CT60) of the CTLA-4 gene. The 49A/G polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism method using the enzyme BseXI and the CT60 polymorphism by real-time polymerase chain reaction. Results were analyzed by chi(2) test and linkage disequilibrium analysis. In a comparison of frequencies of GG genotype, a significant association of 49A/G and CT60 polymorphism existed only for Graves' disease. In the 49A/G polymorphism, the frequency of GG genotype was significantly higher (p = 0.0408) compared with controls; the frequency of the CT60 polymorphism was significantly higher as well (p = 0.0213). The frequencies of AA and AG genotypes in control subjects did not significantly differ from frequencies in AITD patients for both polymorphisms. Our results may therefore lend support to the hypothesis that humoral autoimmunity is correlated with 49A/G and CT60 polymorphisms of the CTLA-4 gene.

Adsorption of radiopharmaceuticals to syringes: setting up a reliable protocol for its assessment.

BACKGROUND: It is well known that various drugs, including radiopharmaceuticals, may adsorb to plastic syringes to different extents. Some reports suggest that adsorption can reach levels of almost 50%. The consequence of adsorption of a radiopharmaceutical and subsequent inadequate dosing can include an inappropriate diagnostic response in patients, an increase in the duration of investigation or treatment, and an increase in cost. AIM: To investigate the extent of adsorption of Tc-succimer to plastic syringes and to set up a reliable protocol for assessment of the extent of retention of drugs to single-use plastic syringes before a new syringe brand and/or radiopharmaceutical are introduced in a nuclear medicine department. METHODS: Radiopharmaceutical kits from two different manufacturers were compared for retention using syringes from three different producers. To assess the influence of dilution on retention, Tc-succimer preparations were further diluted with sodium chloride solution for injection. Syringes were filled to one-third of their capacity and incubated at room temperature before being emptied into vacuum vials. The radioactivity of the syringes was measured before and after emptying. The extent of retained radioactivity was calculated as a percentage of radioactivity in the syringe before emptying. RESULTS: Results show that adsorption of Tc-succimer considerably differs between syringe brands. The adsorption of undiluted Tc-succimer in 30 min may exceed 50%. CONCLUSION: The findings show that measurement of retention in syringes and injection sets should be regarded as an essential aspect of quality assurance before radiopharmaceuticals, syringes and injection sets are used routinely.