Guideline for in vivo- and in vitro procedures for thyroid diseases (version 2)

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 ≤1 ng/ml. Moleculargenetic tests (RET proto-oncogen) 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 ≥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.

Residual kidney function after donor nephrectomy

Aim: We evaluated the long-term residual renal function after donor nephrectomy using 99mTc-mercaptoacetyltriglycin (MAG3)-clearance. Donors, methods: Altogether 49 kidney donors were examined using 99mTc-MAG3-clearance after nephrectomy for donation to a relative (m:f = 11:38; age 55±27 years). The donors were examined 16±8 years postoperatively (1.5-26 years). 42 donors (86%) showed normal creatinine values, whereas the other seven (14%) exhibited slightly elevated levels. 20 donors were examined pre- and postoperatively and compared intraindividually. The kidney function was compared to the age adapted normal values of healthy persons with two kidneys (67–133% of age related mean). Results: After nephrectomy all donors showed a normal perfusion, good secretion, merely physiological intrarenal transit and a normal elimination from the kidneys. The 99mTc-MAG3-clearance was 69 ±15% of the normal mean value of healthy carriers of two kidneys regardless of the gender. 20 donors with a preoperative examination showed a significantly reduced total renal function from 84 ± 15% of the mean normal value preoperatively to 60 ± 15% postoperatively (p <0.0005). 15 donors of this group exhibited a significant functional increase of the residual kidney from 40% initially to 60% after nephrectomy (p = 0.003). No correlation was found between the initial 99mTc-MAG3-clearance measured prior to nephrectomy and the clearance levels after nephrectomy. Also, no correlation between the preoperative 99mTc- MAG3-clearance and the postoperative serum creatinine values could be observed. Altogether, 22% of the donors (11/49) developed arterial hypertension 10 ± 8 years after donation (1-23 years). This corresponds to the normal age prevalence of hypertension in the carriers of two kidneys. Three donors suffered from arterial hypertension prior to the operation. Conclusion: Kidney donors with normal or slightly elevated creatinine values postoperatively show a 99mTc- MAG3-clearance value of 69% of the mean value of healthy carriers of two kidneys. This may serve as a reference value for healthy carriers of one kidney. In our study we demonstrated a good compensation of the contralateral kidney via renal scintigraphy by means of 99mTc-MAG3-clearance.

Guideline for radioiodine therapy for benign thyroid diseases (version 3)

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.

Increased FDG bone marrow uptake after intracoronary progenitor cell therapy

Patients with coronary artery disease who undergo FDG PET for therapy monitoring after intracoronary progenitor cell infusion (PCT) show an increased bone marrow up-take in some cases. Aim of the study was to evaluate the systemic bone marrow glucose metabolism in this patient group after PCT. Patients, methods: FDG bone marrow uptake (BMU), measured as standardized uptake value (SUVmax) in the thoracic spine, was retrospectively evaluated in 23 control patients who did not receive PCT and in 75 patients who received PCT 3 ± 2.2 days before PET scanning. Five out of them were pretreated with granulocyte colony-stimulating factor (G-CSF) 5 days prior to PCT and 10 ± 1.2 days before PET scanning. In 39 patients who received only PCT without G-CSF and underwent PET therapy monitoring 4 months later, baseline and follow up bone marrow uptake were measured. Leucocytes, C-reactive protein (CRP) levels and the influence of nicotine consumption were compared with the BMU. Results: In patients (n = 70) who received PCT without G-CSF, BMU median (1.3) was slightly, but significantly higher than in the controls (1.0) (p = 0.02) regardless nicotine consumption. BMU did not change significantly 4 months later (1.2) (p = 0.41, n.s.). After G-CSF pretreatment, patients showed a significantly higher bone marrow uptake (3.7) compared to patients only treated with PCT (1.3) (p = 0.023). Leucocyte blood levels were significantly higher in patients with a BMU ≥ 2.5 compared to patients with a bone marrow SUVmax < 2.5 (p <0.001). CRP values did not correlate with the BMU (rho -0.02, p = 0.38). Conclusion: Monitoring PCT patients, a slightly increased FDG BMU may be observed which remains unchanged for several months. Unspecific bone marrow reactions after PCT may be associated with increased leucocyte blood levels and play a role in the changed systemic glucose BMU.

18F-Deoxyglucose PET for the staging of oesophageal cancer

Aim: Evaluation of the influence of histopathologic sub-types and grading of primaries of oesophageal cancer, relative to their size and location, on the uptake of 18F-deoxyglucose (FDG) as measured by positron emission tomography (PET). Methods: 50 consecutive patients were evaluated. There were four drop-outs due to previous surgical and/or chemotherapeutical treatments and thus in 46 patients (28 squamous cell carcinomas and 18 adenocarcinomas) a pretherapeutic PET evalution of the primary including a standard uptake value (SUV) was obtained. In 42 cases data on tumour grading were available also. Results: Squamous cell carcinomas (SCC) were in 7/13/8 cases located in the proximal, medial and distal part of the oesophagus, respectively the grading was Gx in 3, G 2 in 12, G2-3 in 7, and G3 in 6 cases. The SUVmax showed a mean of 6.5 ± 2.8 (range 1.7-13.5). Adenocarcinomas (ACA) were located in the medial oesophagus in two cases and otherwise in its distal parts. Grading was Gx in one, G2 in 4, G2-3 in 3, G3 in 3, G3-4 in 3, and G4 in one case. The mean SUVmax was 5.2 ± 3.2 (range 1-13.6) and this was not significantly different from the SCC. Concerning the tumour grading there was a slight, statistically not relevant trend towards higher SUVmax in more dedifferentiated cancer. Discussion: SCC and ACA of the oesophagus show no relevant differences in the FDG-uptake. While there was a significant variability of tumour uptake in the overall study group, a correlation of SUV and tumour grading was not found.

FDG uptake after intraarterial chemotherapy in head and neck cancer

Aim: The intraarterial chemotherapy (i.a. CHT) using high dose cisplatin combined with systemic neutralization in patients with head and neck cancer (HNSCC) is used to reduce the tumor volume preoperatively. Aim of the study is the evaluation of the influence of i.a. CHT on the metabolism of fluor-18-deoxyglucose (FDG) in the primary and lymph nodes (LN). The value of FDG positron emission tomography (PET) preoperative and as follow-up method after i.a. CHT is examined. Patients, methods: Altogether 16 patients with HNSCC underwent two preoperative FDG PET examinations: the baseline examination one week before and the follow-up three weeks after i.a. CHT. The SUVmax values of the primary and the LN and LN metastases were evaluated and compared with each other and the histopathology. Results: The SUVmax value of the primary decreased after i.a. CHT significantly from a median (25th percentile/ 75th percentile) of 6.4 (4.1/ 7.8) to 3.6 (2.4/ 6.7) (p = 0.01). In 11 out of 16 patients cervical LN metastases were detected. The cervical LN metastases showed a decrease of the SUVmax value from 3.6 (2.3/ 4.8) in the pretreatment examination to 2.3 (1.7/ 3.6) after i.a. CHT (p = 0.008). Only in one patient with LN metastases the SUVmax of the nodes increased. The histopathologically measured size of the LN metastases ranged from 2 to 30 mm. Non malignant LN did not reveal a significant SUVmax decrease after i.a. CHT (p = 0.13). Conclusions: As expected, primaries of HNSCC showed a significant reduction of SUV after i.a. CHT. Compared to the primary the SUVmax decrease in LN metastases was less, but also significant. Since cytotoxic levels of cisplatin do not occur systemic, postinflammatory reactions of the LN or a lymphatic drainage of the chemotherapeutic drug into the LN could be an explanation. PET for staging of HNSCC must thus be performed prior to i.a. CHT.

Therapy of hepatocellular carcinoma with iodine-131-lipiodol

Aim: To evaluate the efficacy and tolerance of iodine- 131-lipiodol (131I-lipiodol) for hepatocellular carcinoma (HCC) in German long term patients and comparison with medically treated controls. Patients, Methods: 38 courses of intra-arterial 131I-lipiodol therapy with a total activity up to 6.7 GBq were performed in 18 patients with HCC (6 with portal vein thrombosis). Liver and tumour volume and lipiodol deposition were measured by computed tomography and 131I activity by scintigraphy. Therapeutic efficacy was determined by tumour volume change and matched-pairs analysis in comparison to medically (i.e. tamoxifen or medical support) treated patients. Results: Tumour volume decreased in 20/32 index nodules (63%) after the first course. Repeated therapy frequently resulted in further tumour reduction. Overall response to treatment was partial in 11 nodules, minor response in 4 nodules, and disease was stable in 12 and progressive in 5. Significant response was associated with pretherapeutic nodule volume up to 150 ml (diameter of 6.6 cm). Survival rate after 3, 6, 9, 12, 24 and 36 months was 78, 61, 50, 39, 17, and 6%. Matched-pairs analysis of survival revealed 131I-lipiodol to be superior to medical treatment. The most important side effect was a pancreatitis-like syndrome whereas overall tolerance was good. Conclusion: The long term results confirm that HCC therapy with 131I-lipiodol is effective and probably superior to medical treatment. Tumour nodules of up to 6 cm diameter are well suited for this therapy even in the presence of portal vein thrombosis.

Procedure guidelines for radioiodine therapy of differentiated thyroid cancer (version 2)

The procedure guidelines for radioiodine therapy (RIT) of differentiated thyroid cancer (version 2) are the counterpart to the procedure guidelines for 131I whole-body scintigraphy (version 2) and specify the interdisciplinary guidelines for thyroid cancer of the Deutsche Krebs-gesellschaft 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 ≤1 cm, ablative RIT for mixed forms of anaplastic and differentiated thyroid cancer, and RIT in patients with a measurable or increasing thyroglobulin concentration but without detectable metastases by imaging. The description of the pretherapeutic dosimetry now includes the isotopes 123I and 124I as well as a broader range of the activity of 131I. Activities of 2-5 GBq 131I are recommended for the first ablative RIT. If high accumulative activities of 131I are expected, men who have not yet finished their family planning should be advised to the option of sperm cryoconservation. An interdisciplinary consensus is necessary whether the new TNM-classification (UICC, 6th edition, 2002) will lead to modified recommendations for surgical or nuclear medicine therapy, especially for the surgical completeness and for the ablative RIT of pT1 papillary cancer.

Radioiodtherapie beim differenzierten Schilddrüsenkarzinom

Die Verfahrensanweisung zur Radioiodtherapie beim differenzierten Schilddrüsenkarzinom (Version 4) wurde von einer repräsentativen Expertengruppe im informellen Konsens verabschiedet und entspricht damit einer Leitlinie der ersten Stufe (S1) nach den Kriterien der Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF). Die Verfahrensanweisung ergänzt die S2-Leitlinie zur operativen Behandlung maligner Schilddrüsenerkrankungen um die nuklearmedizinischen Aspekte. Bezüglich der Indikationsstellung zur ablativen Radioiodtherapie beim kleinen papillären Schilddrüsenkarzinom und beim minimal invasiven follikulären Schilddrüsenkarzinom ohne Angioinvasion, bezüglich der empirischen Bemessung der 131I-Therapieaktivität sowie bezüglich der exogenen versus endogenen TSH-Stimulation bei der ablativen Radio-iodtherapie werden Handlungskorridore beschrieben. Der Text enthält die Auswertungen aus der National Cancer Database und der SEER-Database (jeweils USA), wonach die ablative Radioiodtherapie bereits in einer Niedrig-Risiko Konstellation die Überlebensrate verbessert. Der statistische Nachweis eines solchen Nutzens setzt ein nationales Krebsregister mit Langzeitdaten voraus.

Guideline for radioimmunotherapy of rituximab relapsed or refractory CD20+ follicular B-cell nonHodgkin´s lymphoma

This guideline is a prerequisite for the quality management in the treatment of non-Hodgkin-lymphomas using radioimmunotherapy. It is based on an interdisciplinary consensus and contains background information and definitions as well as specified indications and detailed contraindications of treatment. Essential topics are the requirements for institutions performing the therapy. For instance, presence of an expert for medical physics, intense cooperation with all colleagues committed to treatment of lymphomas, and a certificate of instruction in radiochemical labelling and quality control are required. Furthermore, it is specified which patient data have to be available prior to performance of therapy and how the treatment has to be carried out technically. Here, quality control and documentation of labelling are of greatest importance. After treatment, clinical quality control is mandatory (work-up of therapy data and follow-up of patients). Essential elements of follow-up are specified in detail. The complete treatment inclusive after-care has to be realised in close cooperation with those colleagues (haematology-oncology) who propose, in general, radioimmunotherapy under consideration of the development of the disease.

Limitations of dual time point FDG-PET imaging in the evaluation of focal abdominal lesions

Aim: For the evaluation of the diagnostic potential of dual time point FDG positron emission tomography (PET) in patients with suspicious focal abdominal up-take, dual time point PET imaging was compared with clinical findings. Patients, methods: In a prospective study, 56 patients exhibiting a solitary suspicious, intense abdominal FDG uptake, underwent dual time point PET imaging for staging or restaging of different malignant tumors, maximal standardized uptake value (SUVmax) measurements included. The first acquisition was started 64.8 ± 19.5, the second 211.3 ± 52.5 min after FDG injection. The final diagnosis based on CT or MRT imaging and a follow-up period of 12.6 ± 2.8 months. Additionally, colonoscopy was done in 6 patients. In another 6 patients histopathology was obtained from CT guided biopsy. Results: Malignant focal abdominal lesions with a SUVmax <2.5 (n = 4) showed an uptake increase of ≥30%. In the remaining malignant cases with an uptake of ≥2.5 (n = 11), up-take increased in 64% and decreased in 36%. Malignant lesions showing FDG uptake decrease (n = 4) had an initial SUVmax value ≥2.5 and remained with a SUVmax ≥2.5 in the second imaging. In benign lesions with an initial SUVmax ≥2.5 (n = 31), the uptake increased in 17 patients (55%) and decreased in 14 patients (45%). All lesions which changed configuration (33%) were confirmed as benign (n = 5). Conclusion: Using dual time point PET abdominal lesions show a very hetergenous uptake pattern regardless of their dignity. Malignancy can only be reliably excluded in lesions which change their configuration and in lesions with an initial SUVmax value <2.5 combined with an SUV decrease in the delayed imaging. Particularly abdominal lesions which show an initial SUVmax ≥2.5 combined with a SUV increase in the delayed imaging are suspicious for malignancy and need further clarification.

Thyroid sonomorphology, thyroid peroxidase antibodies and thyroid function

Aim: Employees of Sanofi-Aventis Deutschland GmbH underwent thyroid screening in 2006 to assess new data about the prevalence of irregular sonomorphological pattern, elevated thyroid peroxidase antibodies (TPO AB) and thyroid function in an unselected adult German population. Participants, methods: The examination included 700 unselected employees. Blood samples were analyzed for serum TSH and TPO AB, and ultrasound of the thyroid was performed. Results: In 40.7% of the participants (n = 285) an irregular sonomorphological pattern was detected: goiter in 13.7%, nodules in 35.6%, nodular goiter in 8.6% and a hypoechogenic pattern of the thyroid gland in 20.4%. Serum TSH was increased in 3.9% and decreased in 0.6%. Elevated TPO AB values were observed in 13%. Only 1.4% (n= 10) showed elevated TPO AB combined with a TSH increase. Sonomorphological abnormalities were associated with increased TPO AB in 7.1%. Elevated TPO AB was observed significantly more often in combination with sonomorphological pathology (54.9%) than without (45.1%) (p = 0.003). Conclusions: Sonomorphological disorders are still very common in Germany and our results are comparable with previous screening examinations. Elevated TPO AB correlated significantly with the sonomorphological pattern of nodules and goiter. This may reflect an improved iodine supply or a hypertrophic stage of autoimmune thyroiditis in some cases.

[Evaluation of intra- and interobserver agreement of Technetium-99m-sestamibi imaging in cold thyroid nodules]

AIM

A supplementary diagnostic tool in the assessment of cold thyroid nodules is scintigraphic imaging with^99mTc-MIBI. Aim of this study was to investigate the validity of this tool by determining the intra- and interobserver agreement in the assessment of cold thyroid nodules in Tc-MIBI scintigrams.

METHODS

A retrospective study with 284 patients (16-85 years of age, 194 women, 90 men) was performed. They had at least one cold nodule and from each of whom were available at least one^99mTc-MIBI and the Tc- pertechnetate image. Eight physicians, active in nuclear medicine, reviewed the sctinti- grams twice in a random order. They were asked if they considered the combination a match, a mismatch, or inconclusive, and if the early or delayed image was more significant or if there was no difference.

RESULTS

Intraobserver agreement ranged from κ = 0.56 (moderate) to κ = 0.78 (substantial). Interobserver agreement ranged from κ = 0.44 to κ = 0.53 (moderate). Interobserver agreement for observers with more than 5 years of work experience in nuclear medicine ranged from κ=0.61 to κ = 0.70 (substantial), for observers with 2-5 years from κ = 0.53 (moderate) to κ = 0.61 (substantial) and for observers with < 2 years from κ = 0.47 to κ = 0.61. "No difference" was chosen in 70 resp. 77 % of all cases in session 1 resp. 2. The early image was preferred in 26 resp. 20 %, and the delayed one in 3 resp. 4 % of all cases.

CONCLUSION

The values of interobserver agreement of all eight observers show that the assessment of Tc-MIBI scintigrams is subject to a certain variance. Hence, they ought to be finally assessed by observers with at least 5 years of work experience.

Percutaneous thermal microwave ablation of thyroid nodules

Microwave ablation (MWA) is a new minimal invasive method for thermal ablation of benign thyroid nodules. In contrast to well-established radiofrequency ablation (RFA), MWA offers several advantages with similarly successful results. There has not been any use of functional imaging with 99mTc-per- technetate and 99mTc-MIBI-scans as a mere qualitative analysis of this imaging in the field of MWA in Europe until now. The aim of this study has been to demonstrate the feasibility of MWA as well as the applicability of functional imaging to verify effectiveness with a centerspecific score. Patients, methods: 11 patients (5 women, 6 men, average age 62.3 years) with 18 benign thyroid nodules were treated. MWA was operated under local anesthesia with a system working in a wavelength field of 902 to 928 MHz (Avecure MWG881, MedWaves, Inc. San Diego, CA). Pre- and postablative scans were controlled by two specialists in nuclear medicine with longtime work experience. Results: A center specific functional imaging score (CSFIS) was defined, a decrease of 1.4 points at an average was noticeable (range 1-3 points). In 66.7% (n = 12) of all nodules the score decreased by 1 point, 27.8% (n = 5) by 2 points and 5.6% (n = 1) by 3 points. The treatment was well tolerated and no severe complications were observed. Conclusion: The preliminary data suggests that MWA is an effective method to treat benign thyroid nodules. Functional imaging is a promising technique for early verification of effectiveness of thermal ablation.

Is radioiodine therapy conducted too late in patients suffering from thyroid autonomy?

Aim: The effectiveness of radioiodine therapy (RIT) is proven. The aim of this study was to determine, how much time passes between diagnosis of thyroid autonomy or occurrence of functional and/or local symptoms on one hand and RIT on the other hand. Patients, methods: This retrospective study comprises 196 patients, who were treated with radioiodine for thyroid autonomy between 2002 and 2005. Evaluated parameters are begin of functional and/ or local symptoms, first scintigraphy with relevant Tc-Uptake as time point of primary diagnosis of thyroid autonomy and time point of implementation of RIT. Results: Between first scintigraphy with relevant Tc-Uptake and implementation of RIT 0–72 months passed (median: 3 months). 160 patients (81.6%) had a prior diagnosis of goitre by their general practitioner and 163 patients (83.3%) had a prior diagnosis of TSH suppression. The time period between first recommendation of RIT and implementation of RIT was 0–89 months (median: 2 months). In 142 patients (71.4%) functional and/or local symptoms were present over 73 months (median; range: 0–180 months) before the first scintigraphy with therapy relevant Tc-Uptake was conducted. Conclusion: Despite clear recommendations in corresponding guidelines too much time passes between first symptoms (median: 73 months), primary diagnosis of therapy relevant thyroid autonomy (median: 2 months) and implementation of RIT. Patients with functional and/or local symptoms should be examined for thyroid autonomy early. If thyroid autonomy is proven, RIT should be planned immediately, especially in high-risk patients.

Statement and Recommendations on Interventional Ultrasound as a Thyroid Diagnostic and Treatment Procedure

The recently published guidelines of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) on interventional ultrasound (INVUS)-guided procedures summarize the intended interdisciplinary and multiprofessional approach. Herewith, we report on recommendations for interventional procedures for diagnosis and treatment of the thyroid gland.

Further Investigation on High-intensity Focused Ultrasound (HIFU) Treatment for Thyroid Nodules: Effectiveness Related to Baseline Volumes

RATIONALE AND OBJECTIVES

Several minimally invasive thermal techniques have been developed for the treatment of benign thyroid nodules. A new technique for this indication is high-intensity focused ultrasound (HIFU). The aim of this study was to assess effectiveness in varying preablative nodule volumes and whether outcome patterns that were reported during studies with other thermal ablative procedures for thyroid nodule ablation would also apply to HIFU.

MATERIALS AND METHODS

Over the last 2 years, 19 nodules in 15 patients (12 women) whose average age was 58.7 years (36-80) were treated with HIFU in an ambulatory setting. Patients with more than one nodule were treated in multiple sessions on the same day. The mean nodule volume was 2.56 mL (range 0.13-7.67 mL). The therapeutic ultrasound probe (Echopulse THC900888-H) used in this series functions with a frequency of 3 MHz, reaching temperatures of approximately 80°C-90°C and delivering an energy ranging from 87.6 to 320.3 J per sonication. To assess the effectiveness of thermal ablation, nodular volume was measured at baseline and at 3-month follow-up. The end point of the study was the volume reduction assessment after 3 months' follow-up. Therapeutic success was defined as volume reduction of more than 50% compared to baseline. This study was retrospectively analyzed using the Wilcoxon signed rank test and Kendall tau.

RESULTS

The median percentage volume reduction of all 19 nodules after 3 months was 58%. An inverse correlation between preablative nodular volume and percentage volume shrinking was found (tau = -0.46, P < .05). Therapeutic success was achieved in 10 out of 19 patients (53%).

CONCLUSIONS

HIFU of benign thyroid nodules can be carried out as an alternative therapy for nodules ≤3 mL if patients are refusing surgery or radioiodine therapy.

Guideline for radioiodine therapy for benign thyroid diseases (version 4)

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.

Procedure guideline for iodine-131 whole-body scintigraphy for differentiated thyroid cancer (version 3)

Version 3 of the procedure guideline for 131I 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. 131I WBS 3–6 months after 131I ablation remains a standard procedure in an endemic area for thyroid nodules and the high frequency of subtotal surgical procedures. Follow-up without 131I WBS is only justified if the following preconditions are fulfilled: low-risk group pT1–2, pN0 M0 with histopathologically confirmed pN0, 131I uptake <2%, 131I 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 131I WBS 3–6 months after ablation and stimulated Tg is of <2 ng/mL, there will be no need for additional routine 131I WBS. If patients from the high-risk group show normal 131I WBS and stimulated Tg-level of <2 ng/mL 3–6 months after ablation, the follow- up care should include repeated stimulated Tgmeasurements. If the Tg-level remains below 2 ng/mL, an additional 131I WBS will be not necessary. The recommended intervals for stimulated Tg-testing are adapted to the prior intervals for 131I 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 131I WBS.

Procedure guidelines for radioiodine therapy of differentiated thyroid cancer (version 3)

The procedure guideline for radioiodine therapy (RIT) of differentiated thyroid cancer (version 3) is the counterpart to the procedure guideline for 131I 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 131I therapy is given for all differentiated thyroid carcinoma (DTC) >1 cm. Regarding DTC ≤1 cm 131I ablation may be helpful in an individual constellation. Preparation for 131I ablation requires low iodine diet for two weeks and TSHstimulation 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 TSHstimulation (necessary for 131I-therapy in patients with metastases, higher sensitivity of 131I whole-body scan) are discussed. In most centers standard activities are used for 131I ablation. If pretherapeutic dosimetry is planned, the diagnostic administration of 131I should not exceed 1–10 MBq, alternative tracers are 123I or 124I. 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.

Combination of ultrasound guided percutaneous microwave ablation and radioiodine therapy in benign thyroid diseases

Aim: Goiters and thyroid nodules are an ongoing problem in healthcare. There has not been any treatment of goiters and thyroid nodules based on the combined therapy of microwave ablation (MWA) and radioiodine therapy (RIT) until now. In this study the potential benefit of a combined therapy versus single RIT is evaluated in order to achieve improvements concerning 131I-dose and hospitalization time. Patients, material, methods: Ten patients with goiter and benign thyroid nodules or Graves' disease were included. Pre-ablation assessments included sonographical imaging, functional imaging with 99mTc and FNAB to collect data of nodules and total thyroid volume and to exclude malignancy. Prior to treatment, radioiodine uptake test was performed. MWA was operated under local anesthesia with a system working in a wavelength field 902–928 MHz. Post-MWA, thyroid volume was recalculated ultrasonically. Due to reduced vital volume, changes of 131I-dose and hospitalization time could be monitored. Results: Mean absolute thyroid volume reduction by MWA before applying RIT was 22 ± 11 ml, meaning a relative reduction of 24 ± 6% (p < 0.05). Thereby, administered activity could be reduced by 393 ± 188 MBq using the combined therapy, reflecting a relative reduction of 24 ± 6% (p < 0.05). Additionally, mean hospitalization time was decreased by 2.1 ± 0.8 days using MWA prior to RIT, implying a relative reduction of 28 ± 6% (p < 0.05). Conclusion: Depending on ablated volume by MWA, RITmonotherapy requires on average 31.2% more 131I-activity than the combined therapy. The combined therapy remarkably decreases 131I-dose and hospitalization time. The combined MWA and RIT therapy is a considerable, effective and safer alternative to surgery for the treatment of very large benign nodular goiters.

Percutaneous microwave ablation of benign thyroid nodules

Aim: Thyroid nodules represent a common clinical issue. Amongst other minimally invasive procedures, percutaneous microwave ablation (MWA) poses a promising new approach. The goal of this retrospective study is to find out if there is a correlation between volume reduction after 3 months and 99mTcuptake reduction of treated thyroid nodules. Patients, methods: 14 patients with 18 nodules were treated with MWA. Pre-ablative assessment included sonographical and functional imaging of the thyroid with 99mTcpertechnetate and 99mTc-MIBI. Additionally, patients underwent thyroid scintigraphy 24 hours after ablation in order to evaluate the impact of the treatment on a functional level and to ensure sufficient ablation of the targeted area. At a 3-month follow-up, ultrasound examination was performed to assess nodular volume reduction. Results: Mean relative nodular volume reduction after three months was 55.4 ± 17.9% (p < 0.05). 99mTcuptake 24 hours after treatment was 45.2 ± 31.9% (99mTc-MIBI) and 35.7 ± 20.3% (99mTcpertechnetate) lower than prior to ablation (p < 0.05). Correlating reduction of volume and 99mTc-uptake, Pearson's r was 0.41 (p < 0.05) for nodules imaged with 99mTc-MIBI and –0.98 (p < 0.05) for 99mTc-pertechnetate. According to scintigraphy 99.6 ± 22.6% of the determined target area could be successfully ablated. Conclusions: MWA can be considered as an efficient, low-risk and convenient new approach to the treatment of benign thyroid nodules. Furthermore, scintigraphy seems to serve as a potential prognostic tool for the later morphological outcome, allowing rapid evaluation of the targeted area in post-ablative examination.

Thermal ablation of thyroid nodules: are radiofrequency ablation, microwave ablation and high intensity focused ultrasound equally safe and effective methods?

OBJECTIVES

This study compares volume reduction of benign thyroid nodules three months after Radiofrequency Ablation (RFA), Microwave Ablation (MWA) or High Intensity Focused Ultrasound (HIFU) to evaluate which of these methods is the most effective and safe alternative to thyroidectomy or radioiodine therapy.

MATERIAL AND METHODS

Ninety-four patients (39 male, 55 female) with a total of 118 benign, symptomatic thyroid nodules were divided into three subgroups. HIFU was applied to 14 patients with small nodules. The other 80 patients were divided up into two groups of 40 patients each for RFA and MWA in the assumption that both methods are comparable effective. The pre-ablative and post-ablative volume was measured by ultrasound.

RESULTS

RFA showed a significant volume reduction of nodules of 50 % (p<0.05), MWA of 44 % (p<0.05) and HIFU of 48 % (p<0.05) three months after ablation. None of the examined ablation techniques caused serious or permanent complications.

CONCLUSION

RFA, MWA and HIFU showed comparable results considering volume reduction. All methods are safe and effective treatments of benign thyroid nodules.

KEY POINTS

• Thermal Ablation can be used to treat benign thyroid nodules • Thermal Ablation can be an alternative to thyroidectomy or radioiodine therapy • Radiofrequency Ablation, Microwave Ablation, High Intensity Focused Ultrasound are safe and effective.

Minimally invasive local ablative therapies in combination with radioiodine therapy in benign thyroid disease: preparation, feasibility and efficiency - preliminary results

PURPOSE

Initial studies of combinations of radioiodine therapy (RIT) and local ablative procedures for the treatment of thyroid nodules have shown promising results. The goal of this study was to evaluate the effectiveness of RIT combined with radiofrequency ablation (RFA) in patients with goitres and to determine which ablative procedure is the most suitable for a combined therapy.

METHODS

Thirty patients with goitres were divided into two subgroups. A test group of 15 patients received combined therapy (RIT + RFA) and a control group of 15 patients received RIT mono therapy. All patients underwent assessments including ultrasound, laboratory evaluation (T3, T4, TSH, TG, TPOAb, TgAbTRAb) and scintigraphic imaging with Tc-99m-Pertechnetate. The 3-month volume reduction was used to evaluate therapy effectiveness.

RESULTS

Combined therapy (subgroup 1) resulted in a significant (p < 0.05) thyroid volume reduction (22.3 ± 54 ml/32.2 ± 58.2%) with better performance (p > 0.05) than the control group (20.2 ± 32.2 ml/29.6 ± 42.1%). All patients became euthyroid after treatment. No major discomfort or complications occurred. A review of the literature investigating combinations of other local ablative procedures with RIT was performed to determine the most promising combination.

CONCLUSIONS

The present study confirms the positive experiences with the combined therapy of RIT and local ablative procedures shown in the current literature and approves this approach for the treatment of goitres with RFA + RIT. These findings, when confirmed by further studies, should expand the indication of combined therapy as a minimally invasive alternative to surgery.