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Unlabelled: T stage was redefined for patients with differentiated thyroid carcinoma (DTC) between the 5th and 7th versions of the UICC tumour classification system., Patients, Methods: 636 patients (486 women, 150 men; mean age 49.1 ± 15.6 years, mean follow-up 4.6 years) who had been treated with ablative radioiodine therapy after thyroidectomy for papillary (PTC) or follicular thyroid carcinomas (FTC) were retrospectively assessed on occurrence of locoregional recurrent disease, or cervical lymph node or distant metastases. Disease-free survival was calculated from initial T stage, classified according to both versions of the UICC staging system and compared with the prognostic value of primary tumour size. Kaplan-Meier method and two measures of explained variation, (1) R2 based on the (partial) likelihood ratio statistic of the Cox proportional hazards model and (2) a model-free variant of a distance measure proposed by Schemper had the aim to detect the most advantageous classification., Results: Of the 508 patients with PTC, 11 (2.2%) developed a local recurrence, 37 (7.3%) cervical lymph node and 23 (4.5%) distant metastases, 3 (2.3%), 8 (6.3%), and 18 (14.1%) were the numbers for the 128 FTC patients respectively. The two classification systems yielded an equal count of statistically significant differences regarding disease-free survival in patients with PTC while UICC 7th classification appeared slightly advantageous in patients with FTC. Regarding explained variation the UICC 7th classification tended to be superior to the UICC 5th classification, both in PTC and FTC, however statistical significance was not reached., Conclusion: The primary tumour size significantly added to the prognosis regarding local cervical and distant metastases.

Aim: The positive predictive value (PPV) of a slightly elevated basal calcitonin (CT) for the diagnosis of medullary thyroid cancer (MTC) is still under debate., Patients, Methods: A total of 11270 patients with thyroid nodules underwent calcitonin screening. Patients with known elevation of CT, renal insufficiency, bacterial infection, alcohol abuse, proton-pump inhibitor therapy or autoimmune thyroid disease were excluded from further analysis. Serum CT was determined by the solid-phase, enzyme-labeled, two-site chemiluminescent immunoassay Immulite 2000. If possible, a pentagastrin test was done to differentiate cases of hypercalcitoninaemia., Results: Hypercalcitoninsemia was found in 32 patients. 20 patients underwent surgery. In 10 patients a MTC was found. The PPV of hypercalcitoninaemia for MTC was 31%. The PPV increased to 50% for those patients who underwent surgery (10/20). A subgroup of 26 patients presented with basal CT between 13 and 50 pg/ml, 14 of them underwent surgery, in 4 cases evidence of MTC was revealed. This resulted in a PPV of 15% (4/26), although the value increased to 28% when only surgically treated patients were considered (4/14)., Conclusion: Taking all clinical data into account, calcitonin screening has an acceptable PPV for medullary thyroid cancer in patients with thyroid nodules. Therefore, we recommend calcitonin screening in centers for thyroid disorders.

The authors present a procedure guideline for scintigraphic detection of sentinel lymph nodes in malignant melanoma and other skin tumours, in breast cancer, in head and neck cancer, and in prostate and penile carcinoma. Important goals of sentinel lymph node scintigraphy comprise reduction of the extent of surgery, lower postoperative morbidity and optimization of histopathological examination focussing on relevant lymph nodes. Sentinel lymph node scintigraphy itself does not diagnose tumorous lymph node involvement and is not indicated when lymph node metastases have been definitely diagnosed before sentinel lymph node scintigraphy. Procedures are compiled with the aim to reliably localise sentinel lymph nodes with a high detection rate typically in early tumour stages. Radiation exposure is low so that pregnancy is not a contraindication for sentinel lymph node scintigraphy. Even with high volumes of scintigraphic sentinel lymph node procedures surgeons, theatre staff and pathologists receive a radiation exposure <1 mSv/year so that they do not require occupational radiation surveillance.

Unlabelled: The primary aim of this study was to compare pharmacoeconomic effects of hypothyroidism secondary to hormone withdrawal (THW) and recombinant human TSH (rhTSH) for follow-up WBS in patients with differentiated thyroid cancer (DTC). The second aim was to determine patients' preference for one procedure or the other., Patients, Methods: This retrospective survey included 327 patients with DTC who underwent at least one in-hospital WBS with rhTSH between 1999 and 2006. They had also undergone THW for WBS. Patients received a two-page questionnaire via mail addressing five symptoms and ten items regarding managing their daily life which was answered by 61.6%. The responder group did not differ from the entire group. The medical and societal cost of both procedures for diagnostic WBS was calculated including direct and all ascertainable indirect cost for the reference year 2005. A sensitivity analysis included the German DRG system of 2007 and 2010., Results: After THW, 94% of patients reported hypothyroid symptoms. Using rhTSH, symptoms occurred significantly less. As a result, 97% of patients favored rhTSH over THW. Mean absence from salaried work was 12.3 days after THW compared to 4 days with rhTSH. Family members of salaried employees missed 3 and 0.7 workdays after THW and rhTSH, respectively. Almost twice as often, medical attention was sought after THW (36%) compared to rhTSH (19 %). Undergoing THW, 48% of patients still used their car while hypothyroid. Our cost calculation revealed a slight benefit of about 89.00 Euro in favour of rhTSH stimulation., Conclusion: Hypothyroidism after THW causes significant morbidity and safety risks. The clinical and societal benefits associated with rhTSH are roughly gained at equivalent overall cost to that of THW.

Unlabelled: The Multicentre Study Differentiated Thyroid Cancer (MSDS) collective represents a well defined group of patients with locally aggressive thyroid carcinomas (pT4; AJCC/UICC 1997). The aim of the present study was to compare the survival of patients with minimum and extensive extrathyroidal growth according to the new AJCC/UICC TNM staging system 2009., Patients, Methods: The follow-up data of 347 patients were analysed. Patients were reclassified according to the current AJCC/UICC 2009 classification. The event-free and overall survival was evaluated using Kaplan-Meier analysis. In addition, postoperative complications and status of disease were documented., Results: 327 patients were assigned to stage pT3 and 20 patients to stage pT4a, respectively. Median follow-up was 6.1 years (range 0.04-9.8 years). 92.5% of patients reached complete remission. There were 7.8 % recurrences in the thyroid bed, in locoregional lymph nodes and/or in distant sites. The overall survival was >98% both in pT3 and pT4a patients (p = n. s.). In contrast, the event-free survival was significantly less favourable in pT4a patients (p < 0.001). Using multivariate analysis the following parameters were significant predictors of event-free survival: histological tumour type, degree of extrathyroidal extension and nodal metastasis (p < 0.05)., Conclusions: The MSDS patients with locally aggressive differentiated thyroid cancer showed an excellent overall survival during a median follow-up of 6.1 years. According to the current AJCC/UICC 2009 classification, pT3 patients with minimal extrathyroidal extension revealed a significantly better event-free survival than pT4a patients with extensive extrathyroidal growth.

Objectives: Comparison of the binding affinity to a CD30-positive Hodgkin lymphoma (HL) cell line and biodistribution in HL bearing mice of new anti-CD30 radioimmunoconjugates (RICs) of varying structure and labelling nuclides., Methods: The antibodies Ki-4 and 5F11 were radioiodinated by the chloramine T method or labelled with (111)In via p-NCS-Benzyl-DOTA. In addition, the Ki-4-dimer was investigated in the iodinated form. The RICs were analyzed for retained immunoreactivity by immunochromatography. In-vitro binding studies were performed on CD30-positive L540 cell lines. For in-vivo biodistribution studies, SCID mice bearing human HL xenografts were injected with the various radioimmunoconjugates. After 24 h, activities in the organs and tumour were measured for all 5 RICs. Tumour-free animals were studied in the same way with (131)I- Ki-4 24 h p. i. The three RICs with the highest tumour/background ratios 24 h p.i. ((131)I-Ki-4, (131)I-5F11, (111)In-bz-DOTA-Ki-4) were analysed further at 48 h and 72 h., Results: All the RICs were successfully labelled with high specific activities (28-47 TBq/mmol) and sufficient radiochemical yields (>80%). Scatchard plot analysis proved high tumour affinity (KD = 20-220 nmol/l). In-vivo tumour accumulation in % of injected dose per g tissue (%ID/g) lay between 2.6 ((131)I-5F11) and 12.3 % ID/g ((131)I-Ki-4) with permanently high background in blood. Tumour/blood-ratios of all RICs were below one at all time points., Conclusions: In-vitro tumour cell affinities of all RICs were promising. However, in-vivo biokinetics tested in the mouse model did not meet expectations. This highlights the importance of developing and testing further new anti-CD30 conjugates.

Aim: Several authors have investigated the value of technetium-MIBI scanning to predict the dignity of hypofunctioning, cold thyroid nodules (HTN) in regions with differing levels of iodine supply. They concluded that an MIBI scan can exclude thyroid malignancy, although comparisons between the studies are of limited value owing to differences in methodology and wide variations in patient selection criteria. The present study investigates whether the above claim is also valid in Germany, a country with a long-standing and persistent, mild iodine deficiency and a high incidence of nodules in large goiters with a low prevalence of malignancy., Patients, Methods: The study compares the results of 99mTc-MIBI scintigraphy (incl. SPECT and planar images) in HTN (MIBI) with those of fine-needle aspiration biopsy (FNAB) and histology. Of 154 consecutive patients (121 women, 33 men; mean age 56 +/- 12 years), 73 underwent thyroid surgery from which the results of FNAB and MIBI were assessed. Selection criteria were risk estimation or conditions limiting the feasibility of FNAB. The mean thyroid volume was 42 +/- 25 ml, with 2.1 +/- 1.4 nodules per patient., Results: Histology revealed thyroid malignancies in 8 out of 73 patients (11.0%). The negative predictive value for MIBI was 97%, which is comparable to FNAB (94%). However, in 19.5% of patients FNAB was indeterminate. Lower specificity (54%) and low positive predictive value (19%) showed that MIBI accumulation cannot differentiate between malignant and benign thyroid nodules. However, comparison with cytological and/or histological findings indicated that it could distinguish between lesions with differing rates of mitochondrial metabolism., Conclusion: Even in areas of former or mild iodine deficiency MIBI forms a basis for choosing between wait-and-see and surgical strategies if FNAB is unfeasible or not representative. However, even for pathological MIBI results, the prevalence of malignancy is not very high.

Aim: After therapeutical application of radionuclides the patient has to be regarded as a radioactive source. The radiation exposure differs from diagnostic nuclear medicine due to the amount of radioactivity and due to beta-radiation. Measurements of photon dose rates were carried out and estimates of beta-radiation outside the patient using Monte-Carlo methods. Calculations of maximum beta-ranges in tissue were also performed. Detailed knowledge of the radiation exposure close to the patient is of major importance with respect to radiation protection of the staff., Method: Photon dose rates for 32 patients were determined after treatment with [131I]NaI and [131I]meta-iodobenzylguanidin, [32P]Na2HPO4, [90Y]Zevalin and [153Sm]EDTMP. Readings were taken immediately after application at eight distances., Results: For therapies with 131I photon dose rates amount to 2 mSv.h(-1).GBq(-1) close to the patient. Taking the typical activities of 3.7 GBq for thyroid carcinoma and up to 11 GBq for mIBG therapies into account this leads to a considerable radiation exposure of approximately 7.5 mSv/h and 20 mSv/h, respectively. At a distance of 2 m the dose rates fall to 1/100 compared to the vicinity. For 153Sm the maximum of 100 microSv.h(-1).GBq(-1) is significantly lower compared to therapies using radioiodine. After application of 32P or 90Y all photon dose rates are lower (<10 microSv.h(-1).GBq(-1)) but in both cases high energy beta-particles associated with high maximum ranges exceeding 1 cm in tissue have to be considered., Conclusion: The remarkable difference of the dose rates in the vicinity of the radioactive patient compared to readings at 2 m distance underlines the major importance of the distance for radiation protection. After application of nuclides emitting high energy beta-particles their contribution outside the patient should be considered. For typical procedures in the patient's vicinity the radiation exposure of the personnel remains below the annual limit of 20 mSv.

The prevalence of thyroid nodules > or = 1 cm is high in a previously iodine-deficient area. Under the hypothesis, that all patients with such nodules undergo fine-needle aspiration biopsy (FNAB) and that sensitivity and specificity of cytology are calculated with 85%, the positive predictive value of pathologic cytologic finding will reach 1.5% only according to Bayes-theorem. This is clinically unacceptable, as resection will be the consequence in all cases with suspect cytology. Even implementation of a second, independent test (e. g. moleculargenetic testing of thyreocytes, sensitivity to detect mutation 50%, specificity 95%) and application of sequential Bayes-theorem the positive predictive value of combined pathologic findings will increase to 13% only. Nevertheless, 58% out of all thyroid cancer remain undetected by such a sequential algorithm. As a consequence , pre-selection of thyroid nodules for FNAB is required to increase the pretest-probability to at least 5-10%. A combination of sonographic criteria and scintigraphy, even in patients with normal TSH-levels, is suited to selected thyroid nodules for FNAB.

Several population-based studies have shown a significant association between TSH-level and BMI (body mass index). About 30% of the rest energy expenditure are regulated by thyroid hormones, which generated the hypothesis that thyroid hormone substitution with TSH-titration into the lower reference levels may prevent body weight gain. The opposite effect of thyroid hormones is appetite stimulation, which may be responsible for body weight gain in case of substitutive medication. The association between TSH and BMI has become a complex topic in the light of the endocrine activity of adipocytes. Adipocytes are not a silent fat mass, but increase the hormone level of leptin, which influences neurones in the hypothalamus, the thyreotropic axis and TSH secretion. BMI is positively correlated with serum leptin. Elevated leptin levels, endogenous in individuals with high BMI or exogenous after leptin injection for treatment of hypothalamic amenorrhoea, shift TSH in the upper reference level. Borderline elevated TSH levels are reversible in case of body weight reduction in obese persons. It remains unclear whether high TSH levels or high leptin level are responsible for obesity or represent secondary phenomenon. Recommendation for daily practice: Borderline elevated TSH-levels in obese patients will decrease in case of body weight reduction without hormone medication. After definitive treatment of hyperthyroidism patient's history for use of carbohydrates (increased during hyperthyroidism) should be noticed and substitution with thyroid hormones aims at TSH in the lower reference level. As body weight gain is observed in all TSH groups, a special concept for prevention and therapy of obesity (diet, daily exercise, behaviour training) should be initiated early and additionally to medication.

The high negative predictive value of FDG-PET in therapy control of Hodgkin lymphoma is proven by the data acquired up to now. Thus, the analysis of the HD15 trial has shown that consolidation radiotherapy might be omitted in PET negative patients after effective chemotherapy. Further response adapted therapy guided by PET seems to be a promising approach in reducing the toxicity for patients undergoing chemotherapy. The criteria used for the PET interpretation have been standardized by the German study groups for Hodgkin lymphoma patients and will be reevaluated in the current studies.

Aim: After application of radiopharmaceuticals the patient becomes a radioactive source which leads to radiation exposure in the proximity. The photon dose rates after administration of different radiopharmaceuticals used in diagnostic nuclear medicine were measured at several distances and different time intervals. These data are of importance for estimating the exposure of technologists and members of the public., Patients, Method: In this study dose rates were measured for 67 patients after application of the following radiopharmaceuticals: 99mTc-HDP as well as 99mTc-pertechnetate, 18F-fluorodeoxyglucose, 111In-Octreotid and Zevalin and 123I-mIBG in addition to 123I-NaI. The dose rates were measured immediately following application at six different distances to the patient. After two hours the measurements were repeated and--whenever possible--after 24 hours and seven days., Results: Immediately following application the highest dose rates were below 1 mSv/h: with a maximum at 780 microSv/h for 18F (370 MBq), 250 microSv/h for 99mTc (700 MBq), 150 microSv/h for 111In (185 MBq) and 132 microSv/h for 123I (370 MBq). At a distance of 0.5 m the values decrease significantly by an order of magnitude. Two hours after application the values are diminished to 1/3 (99mTc, 18F), to nearly (1/2) (123I) but remain in the same order of magnitude for the longer-lived 111In radiopharmaceuticals., Conclusion: For greater distances the doses remain below the limits outlined in the national legislation.

Unlabelled: AIM of the study was to analyse the influence of a concomitant vitamin D deficiency on the results of (99m)Tc-MIBI studies in patients (pts) with primary hyperparathyroidism (pHPT)., Patients, Methods: Between January 1998 and May 2004, 71 pts with pHPT had undergone operation after a (99m)Tc-MIBI study of whom 54 pts (76%) had normal values of 25-OH-vitamin D3 and 17 pts (24%) had vitamin D deficiency. Results of a dual-phase (99m)Tc-MIBI protocol with SPECT were compared with histopathology., Results: In 54 pts with normal vitamin D values late SPECT images identified more lesions (n=51, sensitivity 91%) than early planar (n=45, sensitivity 82%) or late planar images (n=50, sensitivity 88%). In 17 pts with vitamin D deficiency late SPECT images identified more lesions (n=13, sensitivity 72%) than early planar (n=10, sensitivity 56%) or late planar images (n=10, sensitivity 56%) too. In pts with vitamin D deficiency the sensitivity of a (99m)Tc-MIBI SPECT study was lower than in those with normal vitamin D status (72% vs. 91%) and dependent on the value for PTH. However, the results did not reach statistical significance: early planar: p=0.1625; late planar: p=0.0039; (99m)Tc-MIBI SPECT: p=0.1180., Conclusion: The likelihood of a pathological (99m)Tc-MIBI study being obtained in pts with pHPT is dependent on the parathyroid hormone level. However, a negative influence of a low vitamin D level on the scintigraphic detection rate of a parathyroid adenoma could not be proven which may be due to the low number of pts with vitamin D deficiency.

Aim: To compare the opinions of practitioners in primary care with those of thyroid specialists in Germany on the management of solitary thyroid nodules (Papillon 2005)., Methods: Questionnaires were filled in by 2,191 practitioners and 297 thyroid specialists between June 1 and September 30, 2005. The test cases and their modifications described a solitary thyroid nodule of 2-3 cm with different levels of thyroid function and a hypoechogenic nodule of 1 cm in diameter., Results: TSH determination and sonography were found to be standard procedures, followed by scintigraphy (selected by 84.7% of practitioners and 95.1% of specialists, p < 0.001) and fine needle aspiration cytology (54.5% of practitioners, 57.4% of specialists). For a hypoechogenic nodule calcitonin determination was advocated by 54.0% of endocrinologists and by 32.2% of nuclear medicine physicians (p < 0.001). A euthyroid solitary thyroid nodule would be treated medically by 77.8% of practitioners and by 85.7% of specialists, the combination of levothyroxine and iodine being clearly preferred (60.9% of practitioners and 67.1% of specialists). For a hyperfunctioning nodule the preference of radioiodine therapy was significantly higher in the specialist group (88.8%) than among the practitioners (52.2%)., Conclusions: The main differences of opinion between practitioners and specialists focused on calcitonin screening and referral to radioiodine therapy.

Interactions between brain, psyche and thyroid are known from historical descriptions of thyroidectomy (Kocher) and hyperthyroidism. However, their importance is often underscored in clinical routine. Thyroid hormone deficiency during pregnancy may result in irreversible mental retardation and requires levothyroxine substitution. TSH screening after delivery must identify newborns with congenital hypothyroidism: An early levothyroxine substitution and long term therapy control are required. Hypothyroidism and depression have many symptoms in common. Cognitive deficits and depressive states are often found in overt hypothyroidism, psychotic derangements are rare. Levothyroxine improves hypothyroid symptoms and mental performance, mood and motivation. Psychic symptoms of hyperthyroidism include agitation, irritability, mood disturbances, hyperactivity, anxiousness and even panic attacks. Manic and delusional states are rare. In geriatric patients hyperthyroidism may be oligosymptomatic. In psychiatric patients more frequent but unspecific disturbances of thyroid laboratory values being reversible without specific therapy have to be distinguished from rather rare but causative organic thyroid diseases with therapeutic consequences. Some psychiatric drugs influence thyroid laboratory results. Hypothyroidism in depressive patients is a negative prognostic parameter and requires therapy. Psychiatric symptoms associated with hypothyroidism are usually reversible under levothyroxine within 4-8 weeks. The standard for hypothyroidism is mono-levothyroxine therapy.

Aim: This study was performed to determine the results of ablative radioiodine therapy (RIT) when the achieved dose in the thyroid was above 200 Gy and to characterize predictive factors for treatment outcome., Patients, Methods: A total of 571 consecutive patients were observed for 12 months between July 2001 and June 2004. Inclusion criteria were a confirmed diagnosis Graves' disease, compensation of hyperthyroidism and withdrawal of antithyroid drugs two days before preliminary radioiodine-testing and RIT. The intended dose was 250 Gy and the therapeutically achieved dose was calculated from serial uptake measurements. The end-point measure was thyroid function 12 months after RIT; success was defined as elimination of hyperthyroidism. The relation between success rate and the achieved dose, thyroid volume, age and sex of patients, TSH- and TRAb-values and presence of ophthalmopathy was analysed., Results: Relief from hyperthyroidism was achieved in 96% of patients who received more than 200 Gy, even for thyroid volumes >40 ml. The success of ablative RIT was not influenced by age or sex of patients, or by TSH- or TRAb values or concomitant ophthalmopathy. The mean achieved dose in the thyroid was 298 Gy with a standard deviation of 74.6 Gy., Conclusion: To achieve a dose of over 200 Gy with the above standard deviation, we recommend calculating an intended dose of 250 Gy and using a dosimetric approach with early and late uptake values in the radioiodine test, to allow early therapeutic intervention should the posttherapeutic thyroid dose fall unexpectedly below 200 Gy.

In spite of the fact that the German Society of Endocrinology has recommended calcitonin as screening-parameter the majority of physicians in Germany do not routinely use calcitonin in patients with thyroid nodules to exclude medullary thyroid cancer (MTC). The future revision of the recommendation should describe reference values for each commercially available assay, separately for men and women (basal and after pentagastrin-stimulation), and should define sonomorphological inclusion criteria. The epidemiological database of the prevalence of MTC is controversial and the specificity of basal elevated calcitonin levels is limited up to the 5-fold of the upper reference level. If renal insufficiency, bacterial infection, and an alcohol- or drug-induced stimulation of calcitonin is excluded, hypercalcitoninaemia should be confirmed by a second measurement (if necessary using another assay). Stimulation of calcitonin by use of pentagastrin is mandatory prior to the decision on thyroidectomy. A stimulated calcitonin level < 100 pg/ml justifies "wait and see". If stimulated calcitonin levels range between 100 and 200 pg/ml or higher, the differentiation between C-cell hyperplasia and MTC remains uncertain, especially in men. The implementation of calcitonin-screening requires the definition of sonographic inclusion criteria and validation of each assay. Additional pre-requisites are excellent logistic (short period between blood sampling and start of the laboratory test), knowledge of differential diagnoses, knowledge of the consumption of drugs and alcohol, availability of pentagastrin-testing and of moleculargenetic testing with full information to the patients and sufficient time before the decision on surgery is made. All this and the choice of a skilled surgeon, experienced in thyroidectomy and lymphadenectomy with a low rate of local complications are the rationale to recommend calcitonin-screening primarily in centers for thyroid disorders.

Aim: This study was performed to analyse the impact of the choice of antithyroid drugs (ATD) on the outcome of ablative radioiodine therapy (RIT) in patients with Graves' disease., Patients, Material, Methods: A total of 571 consecutive patients were observed for 12 months after RIT between July 2001 and June 2004. Inclusion criteria were the confirmed diagnosis of Graves' disease, compensation of hyperthyroidism and withdrawal of ATD two days before preliminary radioiodine-testing and RIT. The intended dose of 250 Gy was calculated from the results of the radioiodine test and the therapeutically achieved dose was measured by serial uptake measurements. The end-point measure was thyroid function 12 months after RIT; success was defined as elimination of hyperthyroidism. The pretreatment ATD was retrospectively correlated with the results achieved., Results: Relief from hyperthyroidism was achieved in 96% of patients. 472 patients were treated with carbimazole or methimazole (CMI) and 61 with propylthiouracil (PTU). 38 patients had no thyrostatic drugs (ND) prior to RIT. The success rate was equal in all groups (CMI 451/472; PTU 61/61; ND 37/38; p = 0.22)., Conclusion: Thyrostatic treatment with PTU achieves excellent results in ablative RIT, using an accurate dosimetric approach with an achieved post-therapeutic dose of more than 200 Gy.

The version 3 of the procedure guideline for thyroid scintigraphy is an update of the procedure guideline previously published in 2003. The interpretation of the scintigraphy requires the knowledge of the patients' history, the palpation of the neck, the laboratory parameters and of the sonography. The interpretation of the technetium-99m uptake requires the knowledge of the TSH-level. As a consequence of the improved alimentary iodine supply the (99m)Tc-uptake has decreased; 100,000 counts per scintigraphy should be acquired. For this, an imaging time of 10 minutes is generally needed using a high resolution collimator for thyroid imaging.

The version 3 of the procedure guideline for radioiodine test is an update of the guideline previously published in 2003. The procedure guideline discusses the pros and cons of a single measurement or of repeated measurements of the iodine-131 uptake and their optimal timing. Different formulas are described when one, two or three values of the radioiodine kinetic are available. The probe with a sodium-iodine crystal, alternatively or additionally the gamma-camera using the ROI-technique are instrumentations for the measurement of iodine-131 uptake. A possible source of error is an inappropriate measurement (sonography) of the target volume. The patients' preparation includes the withdrawal of antithyroid drugs 2-3 days before radioiodine administration. The patient has to avoid iodine-containing medication and the possibility of additives of iodine in vitamin- and electrolyte-supplementation has to be considered.

Version 3 of the procedure guideline for (131)I whole-body scintigraphy (WBS) is the counterpart to the procedure guideline for radioiodine therapy (version 3) and specify the interdisciplinary guideline for thyroid cancer of the Deutsche Krebsgesellschaft concerning the nuclear medicine part. (131)I WBS 3-6 months after (131)I ablation remains a standard procedure in an endemic area for thyroid nodules and the high frequency of subtotal surgical procedures. Follow-up without (131)I WBS is only justified if the following preconditions are fulfilled: low-risk group pT1-2, pN0 M0 with histopathologically confirmed pN0, (131)I uptake <2%, (131)I WBS during ablation without any suspicious lesion, stimulated thyroglobulin (Tg)-level 3-6 months after ablation <2 ng/mL, and absence of anti-thyroglobulin-antibodies with normal recovery-testing. If patients from the low-risk group show normal (131)I WBS 3-6 months after ablation and stimulated Tg is of <2 ng/mL, there will be no need for additional routine (131)I WBS. If patients from the high-risk group show normal (131)I WBS and stimulated Tg-level of <2 ng/mL 3-6 months after ablation, the follow-up care should include repeated stimulated Tg-measurements. If the Tg-level remains below 2 ng/mL, an additional (131)I WBS will be not necessary. The recommended intervals for stimulated Tg-testing are adapted to the prior intervals for (131)I WBS-testing in the high-risk group. Increased anti-thyroglobulin-antibodies or incomplete recovery-testing make an individual strategy of follow-up care necessary, which include (131)I WBS.

Aim: Large-scale survey to focus on management of multinodular goiter and to compare the approaches of practitioners in primary care and thyroid specialists in Germany., Methods: Replies to a questionnaire were received from 2,191 practitioners and 297 thyroid specialists between June 1 and September 30, 2005. The hypothetical cases and their modifications described multinodular goiters of different sizes with and without toxic nodules., Results: In the workup, TSH determination and thyroid sonography were found to be standard procedures. Scintigraphy was selected by 80.2% of practitioners and 92.9% of specialists (p < 0.001), in preference to fine needle aspiration cytology (17.9% of practitioners and 34.5% of the specialists, p < 0.001). Only 6.1% of practitioners and 24.4% of specialists (p < 0.001) advocated calcitonin screening. Euthyroid multinodular goiter (50-80 ml) was treated medically by 67.1% of practitioners and 65.6% of specialists, the combination of levothyroxine with iodine being clearly preferred (54.5% of practitioners, 52.3% of specialists). For toxic nodular goiter the preference for radioiodine therapy was significantly higher (p < 0.001) among specialists (67.7%) than among practitioners (47.5%). Referral to surgery was recommended for cold nodules with negative cytology by 64.9% of practitioners and 73.5% of specialists (p = 0.004)., Conclusions: Treatment and diagnostic procedures are used to nearly the same extent in primary care and specialist institutions, but the opinions diverge over the issues of calcitonin screening and referral for radioiodine therapy.

Aim: Graves' hyperthyroidism and antithyroid drugs empty the intrathyroid stores of hormones and iodine. The consequence is rapid 131I turnover and impending failure of radioiodine therapy. Can administration of additional inactive iodide improve 131I kinetics?, Patients, Methods: Fifteen consecutive patients, in whom the 48 h post-therapeutically calculated thyroid dose was between 150 and 249 Gy due to an unexpectedly short half-life, received 3 x 200 microg inactive potassium-iodide (127I) daily for 3 days (Group A), while 17 consecutive patients with a thyroid dose of > or = 250 Gy (Group B) served as the non-iodide group. 48 hours after 131I administration (M1) and 4 or 5 days later (M2) the following parameters were compared: effective 131I half-life, thyroid dose, total T3, total T4, 131I-activity in the T3- and T4-RIAs., Results: In Group A, the effective 131I half-life M1 before iodine (3.81 +/- 0.93 days) was significantly (p < 0.01) shorter than the effective 131I half-life M2 (4.65 +/- 0.79 days). Effective 131I half-life M1 correlated with the benefit from inactive 127I (r = -0.79): Administration of 127I was beneficial in patients with an effective 131I half-life M1 of <3 or 4 days. Patients from Group A with high initial specific 131I activity of T3 and T4 showed lower specific 131I activity after addition of inactive iodine compared with patients from the same group with a lower initial specific 131I activity of T3 and T4 and compared with the patient group B who was given no additional inactive iodide. This correlation was mathematically described and reflected in the flatter gradient in Group A (y = 0.5195x + 0.8727 for 131I T3 and y = 1.0827x - 0.4444 for 131I T4) and steeper gradient for Group B (y = 0.6998x + 0.5417 for 131I T3 and y = 1.3191x - 0.2901 for 131I T4). Radioiodine therapy was successful in all 15 patients from Group A., Conclusion: The administration of 600 microg inactive iodide for three days during radioiodine therapy in patients with Graves' hyperthyroidism and an unexpectedly short half-life of <3 or 4 days was a safe and effective alternative to the administration of a second radioiodine capsule.

The procedure guideline for radioiodine therapy (RIT) of differentiated thyroid cancer (version 3) is the counterpart to the procedure guideline for (131)I whole-body scintigraphy (version 3) and specify the interdisciplinary guideline for thyroid cancer of the Deutsche Krebsgesellschaft concerning the nuclear medicine part. Recommendation for ablative (131)I therapy is given for all differentiated thyroid carcinoma (DTC) >1 cm. Regarding DTC < or =1 cm (131)I ablation may be helpful in an individual constellation. Preparation for (131)I ablation requires low iodine diet for two weeks and TSH-stimulation by withdrawal of thyroid hormone medication or by use of recombinant human TSH (rhTSH). The advantages of rhTSH (no symptoms of hypothyroidism, lower blood activity) and the advantages of endogenous TSH-stimulation (necessary for (131)I-therapy in patients with metastases, higher sensitivity of (131)I whole-body scan) are discussed. In most centers standard activities are used for (131)I ablation. If pretherapeutic dosimetry is planned, the diagnostic administration of (131)I should not exceed 1-10 MBq, alternative tracers are (123)I or (124)I. The recommendations for contraception and family planning are harmonized with the recommendation of ATA and ETA. Regarding the best possible protection of salivary glands the evidence is insufficient to recommend a specific setting. To minimize the risk of dental caries due to xerostomia patients should use preventive strategies for dental hygiene.

Version 4 of the guideline for radioiodine therapy for benign thyroid diseases includes an interdisciplinary consensus on decision making for antithyroid drugs, surgical treatment and radioiodine therapy. The quantitative description of a specific goiter volume for radioiodine therapy or operation was cancelled. For patients with nodular goiter with or without autonomy, manifold circumstances are in favor of surgery (suspicion on malignancy, large cystic nodules, mediastinal goiter, severe compression of the trachea) or in favor of radioiodine therapy (treatment of autonomy, age of patient, co-morbidity, history of prior subtotal thyroidectomy, profession like teacher, speaker or singer). For patients with Graves' disease, radioiodine therapy or surgery are recommended in the constellation of high risk of relapse (first-line therapy), persistence of hyperthyroidism or relapse of hyperthyroidism. After counseling, the patient gives informed consent to the preferred therapy. The period after radioiodine therapy of benign disorders until conception of at least four months was adapted to the European recommendation.

Unlabelled: The need for therapy for nodular goiter results from the growth of thyroid nodules over decades and from the possibility of tracheal compression and worsening of respiratory function. Given the high prevalence of non-toxic goiter, the epidemiologically low incidence of clinically apparent thyroid cancer justifies non-surgical strategies. Randomised studies have shown that levothyroxine offers limited therapeutic effects and is inferior to radioiodine therapy regarding goiter shrinkage. When indication for a definitive therapy is given, the choice between resection and radioiodine therapy should consider volume of goiter, severity of clinical symptoms, thyroid uptake, patient's age, co-morbidity, previous resection of goiter, patient's profession and patient's wish. Even in large goiters between 100 and 300 ml radioiodine therapy showed consistent results with goiter size reduction from 35-40% one year and 40-60% two years after radioiodine therapy. Thyroid hormones to prevent recurrence of goiter are not necessary. Recurrent goiters were seldom observed after radioiodine therapy and resulted from initially very large goiters or uptake in dominate nodules or from low (131)I activities. Recombinant human TSH (rhTSH) offers the opportunity to enhance the effect of radioiodine therapy. Observational studies have shown that rhTSH increases low (131)I uptake in case of high alimentary iodine-supply by the factor 4, causes a more homogenous (131)I distribution within the goiter and improves goiter reduction. A phase I study for dose finding is running in the USA., Conclusion: Radioiodine therapy for shrinkage of large non-toxic goiter should not be restricted to elderly patients, or to patients with co-morbidity or high operative risk, but is an attractive alternative to surgery in patients with special professions (singer, teacher, speaker) or with the wish for a non-invasive treatment modality.

Aim: Targeted radiotherapies using iodine-131 meta-iodobenzylguanidin have long been in use for treatment of stage IV neuroblastoma but reliable dosimetric data are scarce., Method: This work presents an approach to determine the whole body exposure and tumour doses delivered during therapy. Dosimetric data are reported and discussed for six treatments carried out according to the trial protocol NB2004 as it is in use in our study in the last two years., Results: Whole body exposures are found to be in the range of 1.75 to 2.5 Gy whereas tumour doses vary between 15 and 55 Gy., Conclusion: The course of action prescribed by the trial protocol allows whole body exposure as well as tumour doses to be determined routinely.

Aim: (131)I-meta-iodobenzylguanidine ((131)I-MIBG) therapy has been used in neuroblastoma treatment for many years but its value in high intensive first line treatment protocols is not exactly known., Patients, Methods: Stage 4 neuroblastoma patients >1 year with (123)I-MIBG positive residual disease (primary tumour and/or metastasis) after complete induction chemotherapy according to the German neuroblastoma trial NB97 were retrospectively analyzed., Results: One-hundred-eleven patients had (123)I-MIBG positive residual disease after complete induction chemotherapy. Forty patients received (131)I-MIBG therapy using a median activity of 0.44 GBq/kg body weight. By univariate analysis, patients who underwent (131)I-MIBG therapy had a better 3-year event free survival (3-y-EFS 46 +/- 8%) and 3-year overall survival (3-y-OS 58 +/- 9%) than 71 patients without (131)I-MIBG therapy (3-y-EFS 19 +/- 5%, p = 0.003; 3-y-OS 43 +/- 6%, p = 0.037). However, subgroup analysis of 66 patients who underwent high dose chemotherapy with autologous stem cell transplantation (ASCT) during treatment found a very similar outcome with (131)I-MIBG therapy (3-y-EFS 49 +/- 9%, 3-y-OS 59 +/- 10%) and without (131)I-MIBG therapy (3-y-EFS 33 +/- 9%, p = 0.171; 3-y-OS 59 +/- 9%, p = 0.285) due to the dominating effect of ASCT. By multivariate analysis, (131)I-MIBG therapy had no impact on EFS (p = 0.494) and OS (p = 0.891). Only ASCT, external beam radiation therapy and MYCN amplification were important for EFS and OS., Conclusions: An independent advantage of I-131-MIBG therapy could not be proven in this retrospective analysis. The ongoing German Neuroblastoma Trial NB2004 will address the influence of (131)I-MIBG therapy with emphasis on tumour dosimetry.

This overview presents the indications of tumour SPECT in contrast to tumour PET using (18)F-FDG. A number of diagnostic SPECT radiopharmaceuticals have been used for years in oncology and are widely available in nuclear medicine departments. Today, tumour SPECT has to compete with tumour PET using (18)F-FDG. Other PET radiopharmaceuticals are common only in specialised centers. In comparison to SPECT, PET images with their higher resolution are technically superior. Therefore, PET is better than SPECT in localising a tumour, if the special tumour entity accumulates (18)F-FDG. Thus, (18)F-FDG-PET has largely replaced SPECT examinations using (201)Tl chloride, (67)Ga citrate or (99m)Tc anti-CEA. It is questionable whether mammascintigraphy using (99m)Tc-MIBI or (99m)Tctetrofosmine will be broadly accepted in clinical routine. SPECT radiopharmaceuticals are still up to date for examination of tumour entities which do not accumulate (18)F-FDG (e. g. neuroendocrine tumours) and in clinical problem solving if (18)F-FDG-PET is not regarded as superior (e. g. search for recurrent medullary thyroid carcinoma) or in the management of tumours with overlapping diagnosis and therapy as it is the case for differentiated thyroid carcinomas ((123)I/(131)I-NaI), phaeochromozytomas, and neuroblastomas ((123)I/(131)I-MIBG), carcinoids, gastroenteropancreatic tumours, paragangliomas, and Merkel-cell tumours (somatostatin receptor scintigraphy). Future developments concerning new SPECT radiopharmaceuticals and image fusion such as SPECT/CT are expected.

90Y-ibritumomab tiuxetan (Zevalin) is currently approved for radioimmunotherapy of patients with relapsed or refractory follicular non-Hodgkin's lymphoma pretreated with rituximab. Future directions are the combined use of 90Y-ibritumomab tiuxetan as part of the initial treatment and as first-line multi-agent therapy of relapsed disease. Current studies investigate patients with other than follicular indolent histologies, e. g. diffuse large cell lymphoma. Labelling of 90Y ibritumomab tiuxetan is a safe procedure, the radiochemical purity is not disturbed by a higher room temperature or by metallic impurity. Quality control is recommended by thin layer chromatography (TLC), strips >15 cm are favourable. TLC cannot distinguish between the correctly radiolabelled antibodies and radiocolloid impurity. If necessary, additional HPLC should be performed. Radiocolloid impurities are absorbed to the solid phase and do not reach the eluate. If the radiochemical purity test is insufficient (<95%), the additional cleaning using EconoPac 10 DG columns (Biorad, Hercules, CA, USA) is a reliable procedure to reduce the percentage of free radionuclide. However, this procedure is not part of the approval.

Unlabelled: The incidentally detected thyroid nodule using sonography is described as incidentaloma; the most nodules have a diameter up to 1.5 cm. Sonography will detect thyroid nodules in more than 20% of the population in Germany. Epidemiological studies investigating the prevalence of malignancy in such incidentalomas are missing. The incidence of differentiated thyroid cancer is about 3 per 100,000 people and year. However, several monocentric studies have shown a prevalence of malignancy of up to 10% of the thyroid nodules in selected patients' group. The histology did notfound microcarcinomas only, but also small cancer with infiltration of the thyroid capsule, lymph node metastasis or multifocal spread. The studies were not designed for outcome measurement after early and incidental detection of small thyroid cancers. Hypoechogenity, ill defined borders, central hypervascularization or microcalcifications were used as combined criteria for risk stratification. The second method for risk stratification is scintigraphy and further tests are warranted for hypofunctioning nodule > or =1 cm. Additionally, the family history, patient's age <20 years, former radiation of the neck, and measurement of calcitonin should be regarded. Without such a risk stratification selection for fine needle aspiration is impossible. Fine needle aspiration of non-palpable incidentalomas led to non-representative or unequivocal cytological findings in up to 40%. Because better outcome of incidentally detected small thyroid carcinomas is not proved and because sonography, scintigraphy and fine needle aspiration remain imprecise regarding dignity of incidentalomas, fine needle aspiration is not the standard for small, non-palpable thyroid nodules., Conclusion: For management of incidentaloma, sonographically unsuspicious, scintigraphically indifferent (nodules > or =1 cm) and without any risk factors in patients' history, wait and see is justified when patient is informed about the problem.

The version 3 of the guideline for radioiodine therapy for benign thyroid diseases presents first of all a revision of the version 2. The chapter indication for radioiodine therapy, surgical treatment or antithyroid drugs bases on an interdisciplinary consensus. The manifold criteria for decision making consider the entity of thyroid disease (autonomy, Graves' disease, goitre, goitre recurrence), the thyroid volume, suspicion of malignancy, cystic nodules, risk of surgery and co-morbidity, history of subtotal thyroidectomy, persistent or recurrent thyrotoxicosis caused by Graves' disease including known risk factors for relapse, compression of the trachea caused by goitre, requirement of direct therapeutic effect as well as the patient's preference. Because often some of these criteria are relevant, the guideline offers the necessary flexibility for individual decisions. Further topics are patients' preparation, counseling, dosage concepts, procedural details, results, side effects and follow-up care. The prophylactic use of glucocorticoids during radioiodine therapy in patients without preexisting ophthalmopathy as well as dosage and duration of glucocorticoid medication in patients with preexisting ophthalmopathy need to be clarified in further studies. The pragmatic recommendations for the combined use of radioiodine and glucocorticoids remained unchanged in the 3rd version.

The procedure guidelines for radioiodine therapy (RIT) of differentiated thyroid cancer (version 2) are the counter-part to the procedure guidelines for (131)I whole-body scintigraphy (version 2) and specify the interdisciplinary guidelines for thyroid cancer of the Deutsche Krebsgesellschaft and the Deutsche Gesellschaft für Chirurgie concerning the nuclear medicine part. Compared with version 1 facultative options for RIT can be chosen in special cases: ablative RIT for papillary microcarcinoma

Papillary thyroid microcarcinomas

Aim: Assessment of the clinical value of (18)F-FDG-PET for detection of recurrent head and neck cancer, local lymph node involvement and distant metastases comparing a qualitative visual with a semiquantitative analysis (SUV values)., Patients, Methods: Retrospective evaluation of 73 (18)F-FDG PET studies in 55 patients by use of a four-step qualitative visual grading system and calculation of standard uptake values in pathological lesions. Calculation of SUV values in normal regions for generating a map of physiological (18)F-FDG distribution. Correlation to histopathological findings and clinical follow-up., Results: 1. Qualitative visual analysis of (18)F-FDG PET studies: a) local recurrence sensitivity 79%, specificity 97%, positive predictive value 95%, negative predictive value 85%, and diagnostic accuracy 89%; b) local metastatic lymph nodes 100%, 95%, 85%, 100%, 96%; c) distant metastases 100%, 98%, 86%, 100%, 98%, respectively. 2. Semiquantitative analysis had only little incremental, non-significant value in comparison to qualitative visual analysis for the detection of a local recurrence in two patients: a) local recurrence: sensitivity 83%, specificity 100%, positive predictive value 100%, negative predictive value 88%, and diagnostic accuracy 93%; b) local metastatic lymph nodes or c) distant metastases did not change in comparison to qualitative visual analysis., Conclusion: (18)F-FDG PET is an effective tool for re-staging of patients with suspected recurrence after therapy for head and neck cancer.

Cost-effectiveness analyses focused on benign thyroid diseases are under-represented in the literature. The calculation of costs per additionally gained life year is difficult: The benefit of prevention is shifted into the distant future. The influence of an untreated subclinical thyroid disease on life expectancy can only be demonstrated by a long-term follow-up and by epidemiological databases. Iodine supplementation and programs for the prevention of tobacco smoking (primary prevention) are very cost-effective. Smoking increases the risk both of multinodular goiter and of Graves' disease. Screening programs (secondary prevention) are discussed for the laboratory parameters thyrotropin (TSH), calcium and calcitonin. TSH testing seems to be very cost-effective for epidemiological considerations in a certain lifespan (newborn, pregnancy, postpartal, older persons, hospitalisation due to acute diseases) and in persons with previously elevated TPO-antibodies or TSH-values >2 mU/l, but dedicated cost-effectiveness analyses are lacking. On the other hand, the cost-effectiveness of a routine TSH testing beyond the age of 35 years has been shown by a high-quality decision analysis. Therapeutic strategies (tertiary prevention) aim at the avoidance of complications (atrial fibrillation, myocardial infarction, death for cardiac reasons) and of iatrogenic complications. Examples of a tertiary prevention are: firstly the definitive therapy of Graves' disease in patients who have an increased risk of relapse after antithyroid drugs (ATD), secondly the radioiodine therapy for subclinical hyperthyroidism and the radioiodine therapy of large goiters in older patients or in patients suffering from a relevant comorbidity. Cost-effectiveness analyses for different therapeutic strategies of Graves' disease were published using a lifelong time-horizon. The ablative radioiodine dose-regime is cost-effective as a first line therapy if the risk of relapse after ATD exceeds 60%.

Aims: To evaluate studies on the use of positron emission tomography with the glucose analog (18)F-fluoro-deoxyglucose (FDG-PET) for the preoperative staging of patients with non-small cell lung cancer (NSCLC) according to the criteria of evidence based medicine and to discuss the cost-effectiveness of the technique., Methods: Clinical studies published between 1995 and 2002 on the preoperative staging of non-small cell lung cancer were used for this analysis. Studies that did not meet the criteria published by the European Agency for the Evaluation of Medicinal Products (EMEA) were excluded. The validity of the studies was evaluated by a standardized rating system developed by the Agency for Health Care Policy and Research (AHCPR)., Results: For the detection of mediastinal lymph node metastases the mean sensitivity and specificity of FDG-PET on a patient basis is 85% and 87% (16 studies, 1355 patients). In studies that compared FDG-PET and computed tomography (CT) the mean sensitivity of CT was 66% at a specificity of 71%. In the detection of distant metastases FDG-PET correctly changed the tumor stage in 18% of the patients when compared to CT based staging (10 studies, 1073 patients). Five cost effectiveness analyses from the USA, Japan, and Germany concluded that FDG-PET improves the outcome of treatment at reduced or only slightly increased overall costs. Improvement of patient outcome was also demonstrated in a randomized trial, which found that the risk of a futile thoracotomy was reduced by 51% (p=0.003) when FDG-PET was added to the preoperative staging., Conclusion: According to the criteria of the AHCPR the use of FDG-PET for detection of mediastinal lymph node and distant metastases is documented at a level of evidence Ia and Ib, respectively. Since systematic analyses also indicate a favorable cost-effectiveness ratio FDG-PET has to be considered as "strictly indicated" for the preoperative staging of non-small cell lung cancer.

Unlabelled: AIM, METHOD: Recommendations for the use of FDG-PET in relapsed colorectal cancer and the decision of reimbursement should base on published studies and on their level of evidence. Therefore, the PET-studies published between 1997 and 2002 were graded by the bias-criteria, by two rating-systems and by two classification-systems for the level of evidence according to AHCPR (Agency for Health Care Policy and Research) and VHA (Veterans Health Administration)., Results: The recommendation for the use of PET in relapsed colorectal cancer reached the level IIa according to the AHCPR, corresponding to level B according to the VHA. The sensitivity and specificity of FDG-PET were 94% (95% CI: 91-96%) and 78% (95% CI: 69-86%), respectively. Staging was changed correctly in 27% of patients (95% CI: 24-30%). Staging by FDG-PET was incorrect in 4% of the patients (95% CI: 2-5%) compared with the conventional methods. The additional use of PET changed the prospectively defined management plan for 34% of patients (95% CI: 31-38%). Either potentially curative operations were initiated in case of resectable tumour or futile operations were cancelled in case of multiple metastases., Conclusion: The 3-year-survival-rate following surgery would have exceeded 70% if the selection of patients had included an additional PET-examination. The correct selection of patients is requested in the daily routine as well as in the clinical implementation of neoadjuvant therapies to prevent a selection-bias from a suboptimal restaging without PET.

The version 2 of the procedure guideline for iodine-131 whole-body scintigraphy for differentiated thyroid cancer is an update of the procedure guideline published in 1999. The following statements are added or modified: The two alternatives of an endogenous TSH-stimulation by the withdrawal of the thyroidal hormone medication and of an exogenous TSH-stimulation by the injection of the recombinant human TSH (rhTSH) have an equal sensitivity for the diagnostic use of radioiodine and for the measurement of thyroglobulin. Image acquisition under rhTSH is obtained approximately 48 h after the radioiodine administration, while an interval of about 72 h is preferred under endogenous TSH-stimulation. If iodine-negative metastases are expected, the feasibility of scintigraphy using (99m)Tc sestamibi or preferably positron emission tomography using (18)F-fluorodeoxyglucose should be considered. The sensitivity of FDG-PET is increased by TSH-stimulation. Before planning the iodine-131 scintigraphy the patient has to avoid iodine-containing medication and the possibility of additives of iodine in vitamin- and electrolyte-supplementation has to be considered.

The version 2 of the procedure guideline for thyroid scintigraphy is an update of the procedure guideline published in 1999. The procedure guideline considers the current amendment of legislative rules (Richtlinie Strahlenschutz in der Medizin 2002). Indication and use of radiopharmaceuticals have to be confirmed by the specialist in nuclear medicine. Activities of 75 MBq technetium-99m, respectively of 10 MBq iodine-123 should not be exceeded without an individual justification. The interpretation of the scintigraphy requires the knowledge of the patients' history, the palpation of the neck, the laboratory parameters, and of the sonography. The interpretation of the technetium-99m uptake requires the knowledge of TSH concentration.

The version 2 of the guideline for diagnostic standards of thyroid disorders is an update of the guideline published in 1999 and describes standards of in vitro and in vivo procedures. The following statements are modified: In vitro procedures: When measurement of the TSH-receptor antibodies is indicated, the guideline recommends the use of a second generation assay (recombinant human TSH-receptor as antigen). The functional assay sensitivity for the measurement of thyroglobulin should reach a value < or =1 ng/ml. Molecular genetic tests (RET proto-oncogene) are indicated in patients with a newly diagnosed medullary thyroid cancer and in the relatives of patients with hereditary medullary thyroid cancer. In vivo procedures: The sonographic examination should use a probe with a frequency of at least 7.5 MHz. Indications for the thyroid scintigraphy: nodule size > or =1 cm in diameter, autonomous goitre/nodule with clinical or subclinical hyperthyroidism, necessity of a differentiation between Graves' disease and chronic lymphocytic thyroiditis, therapy control after a definitive treatment and - in individual cases - the follow-up of untreated autonomous nodules.

The version 2 of the procedure guideline for radioiodine test is an update of the guideline published in 1999. The following statements were added or modified: The procedure guideline discusses the pros and cons of a single measurement or of repeated measurements of the iodine-131 uptake and their optimal timing. Different formulas are described when one, two or three values of the radioiodine kinetic are available. The probe with a sodium iodide crystal, alternative or additionally the gamma-camera using the ROI-technique are instrumentations for the measurement of iodine-131 uptake. A possible source of error is an inappropriate measurement (sonography) of the target volume. The patients' preparation includes the withdrawal of antithyroid drugs 2-3 days before radioiodine administration. The patient has to avoid iodine-containing medication and the possibility of additives of iodide in vitamin- or electrolyte-supplementation has to be considered.

Aim: The discussion in Germany about the reimbursement of the (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in oncology should make use of the experience from the other European countries., Method: A questionnaire was sent to 23 PET-institutions in Europe, outside from Germany, in January 2003. The questions were about the number of PET-institutions, the regulations for reimbursement, the accepted indications, the recognized types of PET-machines and the level of reimbursement., Results: 16 PET-institutions from 10 different countries answered. The relation of PET-institutions to inhabitants ranged from 1:500,000 (B) and 1:1,000,000 (D, A, CH) to approximately 1:4,000,000 (I, E, F, NL). In Belgium, the Netherlands, France, Great Britain, Italy, Finland, Switzerland, and Spain reimbursement was possible and a broad spectrum of indications was accepted, respectively. The reimbursement was not restricted to official indications. In Germany and Austria PET was not generally covered for the patients insured by the national health insurance. An annual sum of approximately 450,000 euro was granted to the recognized PET-institutions in Belgium and France. In Denmark the clinics and their PET-centres were owned by the government, PET was part of the clinical routine oncology. If PET was separately covered the average level of reimbursement for the whole-body PET using a full-ring detector was 1200 euro. The reimbursement of the coincidence-gammacamera differed from the "dedicated" PET in most European countries., Conclusion: In Europe there is an increasing tendency to cover the well documented PET indications in oncology.

Today, diagnostic and therapeutic strategies of Hodgkin lymphoma (HL) with positron emission tomography and radioimmunotherapy include state-of-the-art nuclear medicine which require the cooperation between oncology and nuclear medicine. The benefit of FDG-PET in HL patients with residual tumor masses consists of its high negative predictive value in the therapy control of the disease. The concept of waitful watching in patients with PET-negative residual masses after BEACOPP-chemotherapy will be evaluated in a large multicenter trial of the GHSG (German Hodgkin Study Group). Radioimmunotherapy has been performed in patients with CD20-positive Non-Hodgkin lymphoma for 10 years with promising results. HL is also an excellent target for immunotherapy due to the expression of antigens such as CD25 and CD30. Thus, a new radioimmunoconstruct consisting of the murine anti-CD30 antibody Ki-4 labeled with iodine-131 was developed for patients with relapsed or refractory HL.

The following article reviews nuclear medicine techniques which can be used for assessment of endocrine disorders of the hypothalamic-pituitary axis. For planar and SPECT imaging somatostatin-receptor- and dopamine-D2-receptor-scintigraphy are the most widely distributed techniques. These nuclear medicine techniques may be indicated in selected cases to answer differential diagnostic problems. They can be helpful to search for presence and localization of receptor positive tissue. Furthermore they can detect metastasis in the rare cases of a pituitary carcinoma. Scintigraphy with Gallium-67 is suitable for further diagnostic evaluation in suspected hypophysitis. Other SPECT radiopharmaca do not have relevant clinical significance. F-18-FDG as PET radiopharmacon is not ideal because obvious pituitary adenomas could not be visualized. Other PET radiopharmaca including C-11-methionine, C-11-tyrosine, F-18-fluoroethylspiperone, C-11-methylspiperone, and C-11-raclopride are available in specialized centers only. Overall indications for nuclear medicine in studies for the assessment of endocrine disorders of the hypothalamic-pituitary-axis are rare. Original studies often report only about a small number of patients. According to the authors' opinion the relevance of nuclear medicine in studies of clinically important endocrinologic fields, e.g. localization of small ACTH-producing pituitary adenomas, tumor localization in ectopic ACTH syndrome, localization of recurrent pituitary tissue, assessment of small incidentalomas, can not be definitely given yet.

At the 15th conference on the human thyroid in Heidelberg in 2001 the following aspects of the radioiodine therapy of benign thyroid disorders were presented: General strategies for therapy of benign thyroid diseases, criterions for conservative or definitive treatment of hyperthyroidism as first line therapy and finally preparation, procedural details, results, side effects, costs and follow-up care of radioiodine therapy as well as legal guidelines for hospitalization in Germany. The diagnosis Graves' hyperthyroidism needs the decision, if rather a conservative treatment or if primary radioiodine therapy is the best therapeutic approach. In the USA 70-90% of these patients are treated with radioiodine as first line therapy, whereas in Germany the conservative therapy for 1-1.5 years is recommended for 90%. This review describes subgroups of patients with Graves' disease showing a higher probability to relapse after conservative treatment. Comparing benefits, adverse effects, costs, and conveniences of both treatment strategies the authors conclude that radioiodine therapy should be preferred as first line therapy in 60-70% of the patients with Graves' hyperthyroidism.