RESUMO
Seventy years after the first successful radioiodine treatment of metastatic differentiated thyroid cancer (DTC), radioiodine (131I) therapy for this type of tumor is still without alternative. During the last decade, some key issues such as individual dosimetry, and preparation of 131I therapy by recombinant human TSH have been addressed, but this has not yet lead to conclusive results; furthermore a number of questions related to indication, preparation, and treatment protocol of 131I therapy still remain unanswered. In this review, we will address the literature pertaining to the latest developments in the field of 131I therapy of advanced DTC and we will give an overview of the state of the art regarding patient preparation, dosimetry, and therapy.
Assuntos
Carcinoma Papilar, Variante Folicular/radioterapia , Diferenciação Celular , Radioisótopos do Iodo/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Carcinoma Papilar, Variante Folicular/secundário , Humanos , Metástase Neoplásica , Neoplasias da Glândula Tireoide/patologia , Tirotropina Alfa/uso terapêuticoRESUMO
AIM: To assess available e-learning concepts and programmes for nuclear medicine at university hospitals in Germany. METHODS: All (34) departments of nuclear medicine at German university hospitals were asked to participate in an anonymized online survey. Questions were categorized into four topics: 1.) clinic and education; 2.) on-site strategies for e-learning; 3.) available e-learning offers and 4.) free text comments on experiences and expectations. All input was reviewed descriptively; free text was analyzed analytically. RESULTS: The response rate was 56% (19/34). 13/19 responses indicated well-defined e-learning strategies, mainly to support frontal teaching courses. Future e-learning perspectives focus on clinical case studies with sufficient imaging materials. Only 7/19 university hospitals operate a centralized e-learning platform (e. g. Moodle). The acceptance of the available e-learning options by the students is considered relatively poor. CONCLUSIONS: Today e-learning concepts for nuclear medicine are available at selected university hospitals only. All responders wish to expand on e-learning but many report the lack of administrative support to do so. These data could be regarded as a basis for discussions of inter-university teaching scenarios.
Assuntos
Processamento Eletrônico de Dados/métodos , Aprendizagem , Medicina Nuclear/educação , Alemanha , Humanos , Estudantes , Inquéritos e Questionários , UniversidadesRESUMO
FDG-PET has been proven to be very sensitive in detecting a large variety of carcinomas. The FDG accumulation in malignant tumors is quite stereotyped and often reflects the aggressiveness of the tumor. Therefore, FDG appears to be suitable to detect unknown primaries independent of the type of disease. Being unaware of the site of the primary and also being unaware of the intensity of glucose metabolism, the interpretation of FDG-PET images needs rules accepting a reduced specificity for the definition of malignancy. However, due to physiological FDG-uptake in the head and neck area, especially in lymphatic tissue and vocal cords, one has to accept a high rate of equivocal findings interpreting FDG-PET alone. In this situation, the use of dual-modality PET/CT is of particular value. It allows for correlating the suspicious or unclear PET finding directly with morphology and by that the rate of false-equivocal or false-positive findings is reduced. In addition, PET/CT can precisely define the site of the PET finding in terms of anatomy, helping to direct the surgeon. This characteristic is of different value depending on the location of the primary and tends to be of utmost importance in the head and neck area. Finally, CT by itself may contribute with the detection of PET-negative findings. Thus in conclusion, PET and PET/CT can help localize the primary in CUP in approximately 40% of all cases, even after a thorough work-up with a variety of other investigations.
Assuntos
Neoplasias Primárias Desconhecidas/diagnóstico , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Compostos RadiofarmacêuticosRESUMO
AIMS: Objective of this prospective study was to evaluate the role of somatostatin receptor scintigraphy (SRS) in advanced renal cell carcinoma (RCC) with respect to potential therapy with somatostatin analogue (SST-A) and to assess the response rate under therapy with SST-A. PATIENTS, METHODS: 16 patients with documented progression of histologically confirmed advanced RCC were included. Planar whole-body SRS was performed 4, 24 and 48 h post i.v. injection of 175-200 MBq 111In-pentetreoide. 5 and 25 h p.i. SPECT of thorax and abdomen were performed. Documentation of somatostatin receptor expression via SRS in >50% of known tumour lesions was the criteria for treatment start with SST-A (Sandostatin LAR-Depot 30 mg i.m. every four weeks). RESULTS: In 9/16 of the patients SRS showed at least one metastasis with moderate (n = 5) or intense (n = 4) tracer uptake. Lesion-based SRS evaluation showed only 12.1% (20/165) of all metastases. Most false-negative lesions were located in the lungs. In two patients, the majority of the known metastases was SRS positive and these patients received SST-A therapy. The first radiographic evaluation after a two-month interval showed progressive disease in both patients. CONCLUSIONS: We conclude that SRS is of limited value in staging of advanced RCC. In our patients SST-A did not result in a growth control of RCC. Consequently, the use of SST-A in advanced RCC seems to be no relevant therapeutic option.
Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Cintilografia/métodos , Receptores de Somatostatina/análise , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Idoso , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/epidemiologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do TratamentoRESUMO
BACKGROUND: Hybrid PET/CT and PET/MRI are increasingly important technologies in the evaluation of malignancy and require cooperation between radiologists and specialists in molecular imaging. The aim of our study was to probe the mindsets of radiological and nuclear medicine professionals in regard to current hybrid imaging practice and to assess relevant training aspirations and perceived shortfalls, particularly amongst young professionals. In this context, we initiated an international survey on "Hybrid Imaging Training". METHODS: An online survey was prepared on-line and launched on October-2, 2016. It was composed of 17 multiple-choice and open questions regarding the professional background, a perspective on hybrid imaging training efforts and lessons to be learned from disparate craft groups. The survey ran for 2 weeks. We report total responses per category and individual free-text responses. RESULTS: In total, 248 responses were collected with a mean age of all responders of (41 ± 11) y. Overall, 36% were within the target age range of (20-35) y. Across all responders, the majority (72%) commented on there being too few hybrid imaging experts in their country, whereas only 1% said that there were too many. Three quarters of the responders were in favour of a curriculum allowing sub-specialisation in hybrid imaging. With respect to reporting of hybrid imaging, confidence increased with age. The average rating across all responders on the level of cooperation among the two specialties suggested a low overall level of satisfaction. However, the survey feedback indicated the local (on-site) cooperation being somewhat better than the perceived cooperation between the relevant associations on a European level. CONCLUSION: We consider these results to represent an appropriate cross-section of professional opinions of imaging experts across different demographic and hierarchical levels. Collectively they provide evidence supporting a need to address current shortfalls in developing hybrid imaging expertise through national educational plans, and, thus, contribute to helping improve patient care.
Assuntos
Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Radiologistas/educação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
AIM: Publications on 124-iodine (124I-)-positron emission tomography/computed tomography (PET/CT) dosimetry contain few if any data on pediatric patients with differentiated thyroid carcinoma (DTC). Aim of our study is to determine safety and informativeness of 124I-PET/CT dosimetry in DTC patients
Assuntos
Tomografia por Emissão de Pósitrons , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/radioterapia , Adolescente , Criança , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Metástase Linfática , Masculino , Tomografia por Emissão de Pósitrons/efeitos adversos , Radiografia , Dosagem Radioterapêutica , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/mortalidadeRESUMO
PURPOSE: This study evaluated the impact of (124)I-positron emission tomography (PET) dosimetry on post-primary surgery therapy in radioiodine-naïve patients with advanced differentiated thyroid cancer (DTC). PATIENTS, MATERIAL, METHODS: In each of 28 thyroidectomized patients with high-risk DTC (one or more of pT4, pN1 or pM1), we gave 23-50 MBq of (124)I as an oral capsule and performed PET dosimetry to calculate the individualized therapeutic (131)I activity that would, insofar as possible, achieve a radioiodine dose >or=100 Gy to all metastases without exceeding 2 Gy to the blood (a surrogate for bone marrow toxicity). We thus determined the absorbed lesion dose per GBq of administered 131I activity (LDpA) based on serial PET (4, 24, 48, 72 and 96 h after oral 124I intake) and PET/computed tomography (25 h after (124)I intake) and the critical blood activity (CBA) based on blood and whole-body radiation counting (2, 4, 24, 48, 72, 96 h after 124I intake). We compared the dosimetry-based interventions with our standard empirical protocol. RESULTS: 25 patients had a total of 126 iodine-positive metastases. 18 (72%) of the 25 had solely iodine-avid metastases, while seven (28%) had both iodine-avid and -non-avid metastases. In two patients (8%), none of the iodine-avid metastases could have been practically treated with a sufficient radiation dose. Relative to the empirical protocol, (124)I-PET dosimetry findings changed management in 7 (25%) patients, e.g. allowing application of activities >11 GBq (131)I. Further changes included implementation of hematological back-up in a patient found to be at risk of life-threatening marrow toxicity, and early multimodal therapy in 9 (32%) patients. CONCLUSION: 124I-PET dosimetry is a useful routine procedure in advanced DTC and may allow safer or more effective radioiodine activities and earlier multimodal interventions than do standard empirical protocols.
Assuntos
Radioisótopos do Iodo , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Dosagem Radioterapêutica , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/cirurgia , TireoidectomiaRESUMO
AIM: We assess the perspective of patients with thyroid disease towards radiation and radioactivity by means of a cultural-anthropological approach based on qualitative measures and quantitative scores. From the interviews with the patients we evaluate as to how much radioactivity is accepted as an abstract term or as a benefit within the medical context. PATIENTS, METHODS: 68 patients with autonomously functioning thyroid lesions (35 women, 33 men, 32-81 years) were included in this study. All patients were interviewed in an open dialogue with the principal investigator. Patients were asked to describe their attitude towards radioactivity in general and towards radioiodine therapy in particular. Patients were asked to use a scoring system (1 = positive, 5 = negative) to quantify their attitudes. RESULTS: The responses of all patients towards radioactivity in general were heterogeneous with most responses reflecting a negative perception. Many patients expressed their associated fears about atomic energy, malignant diseases and radioactive contamination. The scoring system reflected a mostly negative opinion base. However, patients became more positive once they assumed an immediate benefit of radioactivity for the treatment of their own disease (p = 0.01). CONCLUSIONS: Knowing about significant differences in patient's perception about radioactivity in general or in the clinical context may help to optimise and tailor the initial, pre-therapeutical interview towards the patient.
Assuntos
Radioisótopos do Iodo/efeitos adversos , Doenças da Glândula Tireoide/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Entrevistas como Assunto , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
AIMS: c-erbB-2 overexpression has been shown to be a potential marker of aggressive biological behaviour in a varity of tumours, whereas its role played in thyroid papillary thyroid carcinoma (PTC) remains unclear. Objective of the study is to determine whether c-erbB-2 overexpression correlates with the clinical course. METHODS: We have studied 32 PTC by a two-step immunocytochemical staining procedure for paraffin-embedded specimens (DAKO Hercep-Test). Semiquantitative evaluations were performed, based on the intensity of immunostaining and the percentage of tumor cells. RESULTS: 34% (11/32) of the PTC showed a membranous overexpression of the HER2/neu oncoprotein. Correlating the pathological and clinical data revealed that 81% (9/11) c-erbB-2 positive patients and only 33% (7/21) c-erbB-2 negative patients developed a tumor recurrence or a progression (p = 0.02 in Fisher's exact test). 3/11 c-erbB-2 positive patients died from PTC whereas all (21/21) c-erbB-2 negative patients are still alive (p = 0.03). CONCLUSIONS: Our results strongly suggest that c-erbB-2 oncoprotein overexpression is related to the clinical course of PTC.
Assuntos
Carcinoma Papilar/patologia , Receptor ErbB-2/metabolismo , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos RetrospectivosRESUMO
Fluorine-18 fluordeoxyglucose positron emission tomography (FDG-PET) is an useful tool in diagnosing and monitoring of malignant cutaneous melanoma. However, the feasibility and usefulness of FDG-PET in uveal melanoma is not yet established. We present a patient with suspected advanced uveal melanoma who underwent combined FDG-PET/computed tomography (CT) for staging. FDG-PET/CT images demonstrated vital intraocular tumor. Anatomical assignment of the malignancy to the choroid was possible by means of the coregistered computed tomography. Furthermore, PET revealed an unknown otherwise undetected vital liver metastasis. We conclude that combined FDG-PET/CT has potential to further improve staging and therapy planning in patients with advanced uveal melanoma.
Assuntos
Fluordesoxiglucose F18 , Melanoma/diagnóstico , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Neoplasias Uveais/diagnóstico , Idoso , Enucleação Ocular , Feminino , Humanos , Melanoma/cirurgia , Estadiamento de Neoplasias , Neoplasias Uveais/cirurgiaRESUMO
ABSTRACT A 32-year-old woman with a history of pelvic sarcoma underwent whole-body fluorine-18 fluorodeoxyglucose positron emission tomography (PET) and computed tomographic (CT) fusion imaging for restaging after primary surgery and adjuvant combined radiation and chemotherapy. Interpreting the PET images alone showed an area of focal tracer accumulation in the pelvic floor and was interpreted as being secondary to urine contamination. Image fusion with fully coregistered CT scans showed a localized site of increased uptake from a metastasis to the labia, which was confirmed by biopsy. The presented case illustrates the usefulness of combined PET/CT fusion imaging to overcome some pitfalls of PET imaging alone (eg, differentiating malignant tumor from pooling of tracer in the genitourinary tract or contamination).
Assuntos
Neoplasias Pélvicas/diagnóstico por imagem , Sarcoma/diagnóstico por imagem , Técnica de Subtração , Neoplasias Vulvares/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Erros de Diagnóstico , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Aumento da Imagem/métodos , Valor Preditivo dos Testes , Radiografia , Cintilografia , Compostos Radiofarmacêuticos , Sarcoma/secundário , Neoplasias Vulvares/secundárioRESUMO
AIM: This survey gathers information about clinical SPECT/CT operations worldwide to help guide standardization of clinical SPECT/CT imaging. METHODS: An international, web-based survey of SPECT/CT users was initiated in 12/2010 through an e-mail distribution. Users were asked 71 questions related to (A) demographics, (B) SPECT/CT operations/utilization and (C) variations in imaging protocols. RESULTS: Collected responses originated from 117 imaging centers in the Americas (66%), Europe (20%), Asia-Pacific (11%) and the Middle-East (3%), with the majority of responding sites representing public health care institutions (69%). Most sites operate 1-2 SPECT/CT-systems (74%), typically installed in Nuclear Medicine departments (84%) with extensive prior SPECT-only experience (82%). Only 14% of SPECT/CTs are installed in Radiology departments. Clinical SPECT/CT imaging is performed either as routine (51%) or ad-hoc "add-on" procedure (49%) with a high inter-site and inter-examination variability. The main application of the integrated CT is to provide anatomical localization of the tracer uptake rather than to produce contrast-enhanced or other high-quality CT images. Consequently, in only 22% of the sites a CT contrast injector is installed. Only 6% of centers use SPECT/CT devices for stand-alone CT procedures. CONCLUSION: An international survey among clinical SPECT/CT users revealed that SPECT/CT is a not a routine component of nuclear medicine procedures. The majority of the centers responding do not fully utilize the diagnostic potential of the CT components. Significant variations in standard imaging protocols were observed. These findings illustrate the need for training and standardization and underscore the need for revisiting the role of SPECT/CT in diagnostic imaging.
Assuntos
Pesquisas sobre Atenção à Saúde , Imagem Multimodal/estatística & dados numéricos , Medicina Nuclear/estatística & dados numéricos , Tomografia por Emissão de Pósitrons , Padrões de Prática Médica/estatística & dados numéricos , Tomografia Computadorizada por Raios X , InternacionalidadeRESUMO
The technical developments that have taken place in the preceding years (PET, hybrid imaging) have changed nuclear medicine. The future cooperation with radiologists will be challenging as well as positioning nuclear medicine in an European context. It can also be expected that education in nuclear medicine will undergo a harmonization process in the states of the European Union. In this paper, we describe how nuclear medicine education is organized in several European countries. We aim to stimulate constructive discussions on the future development of the specialization in nuclear medicine in Germany.
Assuntos
Diagnóstico por Imagem/tendências , Medicina Nuclear/educação , Europa (Continente)RESUMO
AIM: Recombinant human thyroid-stimulating hormone (rhTSH) recently was approved as an alternative to thyroid hormone withholding (THW) to elevate TSH for thyroid remnant ablation in differentiated thyroid carcinoma patients. High ablation success rates are reported with diverse rhTSH-aided (131)I activities. Improved renal function causes approximately 50% faster radioiodine clearance under euthyroidism versus hypothyroidism. Knowledge of comparative remnant radioiodine kinetics, particularly the remnant radiation dose in Gy/GBq of administered (131)I activity (RDpA), could assist in choosing rhTSH-aided ablative activities. MATERIAL AND METHODS: To compare the RDpA, determined through (124)I-positron emission tomography/computed tomography (PET/CT), under the two stimulation methods, we retrospectively divided into two groups 55 consecutive totally-thyroidectomized, radioiodine-naïve patients. The rhTSH group (n=16) received (124)I on thyroid hormone, 24 h after two consecutive daily intramuscular injections of rhTSH, 0.9 mg. The THW group (n=39) received (124)I after weeks-long THW, when serum TSH first measured > or = 25 mIU/L. We performed PET investigations 4 h, 24 h, 48 h, 72 h and 96 h and PET/CT 25 h after (124)I administration. RESULTS: Median stimulated serum thyroglobulin was 15 times higher (p=0.023) and M1 disease almost twice as prevalent (p=0.05) in rhTSH versus THW patients. Mean+/-standard deviation RDpA was statistically equivalent between the groups: rhTSH, 461+/-600 Gy/GBq, THW, 302+/-329 Gy/GBq, two-sided p=0.258. CONCLUSIONS: rhTSH or THW deliver statistically equivalent radiation doses to thyroid remnant and may be chosen based on safety, quality-of-life, convenience and pharmacoeconomic factors. Institutional fixed radioiodine activities formulated for use with THW need not be adjusted for rhTSH-aided ablation.
Assuntos
Técnicas de Ablação , Carcinoma Papilar/radioterapia , Tomografia por Emissão de Pósitrons , Neoplasias da Glândula Tireoide/radioterapia , Tireotropina/uso terapêutico , Suspensão de Tratamento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tireoglobulina/sangue , Hormônios Tireóideos/sangue , Hormônios Tireóideos/efeitos da radiação , Resultado do Tratamento , Adulto JovemAssuntos
Adenocarcinoma Folicular/patologia , Radioisótopos do Iodo , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma Folicular/diagnóstico por imagem , Adenocarcinoma Folicular/radioterapia , Idoso , Transporte Biológico , Humanos , Radioisótopos do Iodo/farmacocinética , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios XRESUMO
Nuclear medicine imaging techniques allow the noninvasive in vivo visualization of cellular and subcellular molecular processes. In the context of lymph node surgery and patient management in uro-oncology, two molecular nuclear imaging techniques deserve special interest: positron emission tomography (PET) for staging, restaging, and follow-up, and preoperative identification and subsequent biopsy of the sentinel lymph node (the first lymph node in the lymphatic drainage system of the tumor). Both methods and their clinical potential are described in this review. Future trends in molecular imaging in uro-oncology are also discussed.