[The clinical impact of amino acid positron emission tomography measurements in the treatment of primary malignant brain tumors]. / Az aminosav-pozitronemissziós tomográfiás mérések klinikai jelentosége a primer rosszindulatú agydaganatok kezelésében.

Despite the large-scale diagnostic and therapeutic progress of recent years, the heterogeneity and therapeutic management of adult primary malignant brain tumors pose a significant challenge to the attending physician. Based on the research and experience accumulated over the past two decades, the range of patients who can benefit the most from complex oncology treatment has been outlined, and it has been confirmed that a reliable complex diagnostic background is essential for adequate therapeutic management. However, after some necessary therapeutic steps, the "gold standard" magnetic resonance imaging (MRI) is not always able to accurately assess and diagnose post-therapeutic conditions. Thanks to the collaboration of the nuclear medicine and neuro-oncology professions, more and more types of radiotracer compounds are now available in more and more centers, including amino acid ligands and thus, positron emission tomography (PET) examinations with the radiopharmaceutical O-(2-[18F]fluoroethyl)-L-tyrosine. The metabolic state, as a kind of fourth dimension of imaging, is an essential part of adequate modern diagnostics. Combining advanced MRI techniques and PET-based (PET/CT, PET/MRI) measurements with a suitable tracer can place therapeutic decisions on a reliable basis. We present the clinical significance of amino acid-PET-based hybrid nuclear medicine imaging studies in the therapeutic management of these patients by reviewing the literature data on the practice of the method in Hungary and abroad and presenting the results of our retrospective summary research so far. Orv Hetil. 2023; 164(32): 1247-1255.

Therapy Defining at Initial Diagnosis of Primary Brain Tumor-The Role of 18F-FET PET/CT and MRI.

Primary malignant brain tumors are heterogeneous and infrequent neoplasms. Their classification, therapeutic regimen and prognosis have undergone significant development requiring the innovation of an imaging diagnostic. The performance of enhanced magnetic resonance imaging depends on blood-brain barrier function. Several studies have demonstrated the advantages of static and dynamic amino acid PET/CT providing accurate metabolic status in the neurooncological setting. The aim of our single-center retrospective study was to test the primary diagnostic role of amino acid PET/CT compared to enhanced MRI. Emphasis was placed on cases prior to intervention, therefore, a certain natural bias was inevitable. In our analysis for newly found brain tumors 18F-FET PET/CT outperformed contrast MRI and PWI in terms of sensitivity and negative predictive value (100% vs. 52.9% and 36.36%; 100% vs. 38.46% and 41.67%), in terms of positive predictive value their performance was roughly the same (84.21 % vs. 90% and 100%), whereas regarding specificity contrast MRI and PWI were superior (40% vs. 83.33% and 100%). Based on these results the superiority of 18F-FET PET/CT seems to present incremental value during the initial diagnosis. In the case of non-enhancing tumors, it should always be suggested as a therapy-determining test.

Use of Diagnostic Imaging Modalities in Modern Screening, Diagnostics and Management of Breast Tumours 1st Central-Eastern European Professional Consensus Statement on Breast Cancer.

Breast radiologists and nuclear medicine specialists updated their previous recommendation/guidance at the 4th Hungarian Breast Cancer Consensus Conference in Kecskemét. A recommendation is hereby made that breast tumours should be screened, diagnosed and treated according to these guidelines. These professional guidelines include the latest technical developments and research findings, including the role of imaging methods in therapy and follow-up. It includes details on domestic development proposals and also addresses related areas (forensic medicine, media, regulations, reimbursement). The entire material has been agreed with the related medical disciplines.

PET/MRI in the Presurgical Evaluation of Patients with Epilepsy: A Concordance Analysis.

The aim of our prospective study was to evaluate the clinical impact of hybrid [18F]-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging ([18F]-FDG PET/MRI) on the decision workflow of epileptic patients with discordant electroclinical and MRI data. A novel mathematical model was introduced for a clinical concordance calculation supporting the classification of our patients by subgroups of clinical decisions. Fifty-nine epileptic patients with discordant clinical and diagnostic results or MRI negativity were included in this study. The diagnostic value of the PET/MRI was compared to other modalities of presurgical evaluation (e.g., electroclinical data, PET, and MRI). The results of the population-level statistical analysis of the introduced data fusion technique and concordance analysis demonstrated that this model could be the basis for the development of a more accurate clinical decision support parameter in the future. Therefore, making the establishment of "invasive" (operable and implantable) and "not eligible for any further invasive procedures" groups could be much more exact. Our results confirmed the relevance of PET/MRI with the diagnostic algorithm of presurgical evaluation. The introduction of a concordance analysis could be of high importance in clinical and surgical decision-making in the management of epileptic patients. Our study corroborated previous findings regarding the advantages of hybrid PET/MRI technology over MRI and electroclinical data.

[Nuclear medicine techniques in the diagnosis of pancreatic cancer]. / Nukleáris medicinai módszerek a hasnyálmirigy-daganatok diagnosztikájában.

The prognosis of pancreatic cancer is closely related to the histological origin of the tumors and the stage of the disease. As recognition is advanced in most cases, treatment options are limited. The development of nuclear medicine hybrid techniques (SPECT/CT, PET/CT, PET/MRI) and new therapies plays an important role in the recognition and treatment of pancreatic tumors. These measurements are useful in characterizing biological behavior, based on which tumors can be recognized at an early stage, promote the treatment, the selection of optimal therapies (e.g., targeted therapies). The authors discuss the role of nuclear medicine techniques in the management of patients suffering from pancreatic tumors.

The role of hybrid FDG-PET/MRI on decision-making in presurgical evaluation of drug-resistant epilepsy.

BACKGROUND: When MRI fails to detect a potentially epileptogenic lesion, the chance of a favorable outcome after epilepsy surgery becomes significantly lower (from 60 to 90% to 20-65%). Hybrid FDG-PET/MRI may provide additional information for identifying the epileptogenic zone. We aimed to investigate the possible effect of the introduction of hybrid FDG-PET/MRI into the algorithm of the decision-making in both lesional and non-lesional drug-resistant epileptic patients. METHODS: In a prospective study of patients suffering from drug-resistant focal epilepsy, 30 nonlesional and 30 lesional cases with discordant presurgical results were evaluated using hybrid FDG-PET/MRI. RESULTS: The hybrid imaging revealed morphological lesion in 18 patients and glucose hypometabolism in 29 patients within the nonlesional group. In the MRI positive group, 4 patients were found to be nonlesional, and in 9 patients at least one more epileptogenic lesion was discovered, while in another 17 cases the original lesion was confirmed by means of hybrid FDG-PET/MRI. As to the therapeutic decision-making, these results helped to indicate resective surgery instead of intracranial EEG (iEEG) monitoring in 2 cases, to avoid any further invasive diagnostic procedures in 7 patients, and to refer 21 patients for iEEG in the nonlesional group. Hybrid FDG-PET/MRI has also significantly changed the original therapeutic plans in the lesional group. Prior to the hybrid imaging, a resective surgery was considered in 3 patients, and iEEG was planned in 27 patients. However, 3 patients became eligible for resective surgery, 6 patients proved to be inoperable instead of iEEG, and 18 cases remained candidates for iEEG due to the hybrid FDG-PET/MRI. Two patients remained candidates for resective surgery and one patient became not eligible for any further invasive intervention. CONCLUSIONS: The results of hybrid FDG-PET/MRI significantly altered the original plans in 19 of 60 cases. The introduction of hybrid FDG-PET/MRI into the presurgical evaluation process had a potential modifying effect on clinical decision-making. TRIAL REGISTRATION: Trial registry: Scientific Research Ethics Committee of the Medical Research Council of Hungary. TRIAL REGISTRATION NUMBER: 008899/2016/OTIG . Date of registration: 08 February 2016.

[Radiology/Nuclear Medicine Group. Use of imaging methods in the current screening, diagnostics and treatment of breast cancer - Professional guidelines. 4th Breast Cancer Consensus Conference]. / A képalkotó vizsgálómódszerek alkalmazása az emlodaganatok korszeru szurésében, diagnosztikájában és ellátásában ­ Szakmai útmutató a IV. Emlorák Konszenzus Konferencia alapján.

Breast radiologists and nuclear medicine specialists have updated their previous recommendation/guidance at the 4th Hungarian Breast Cancer Consensus Conference. They suggest to adopt this actual protocol for the screening, diagnostics and treatment of breast tumors from now on. This recommendation includes the description of the newest technologies, the recent results of scientific research, as well as the role of imaging methods in the therapeutic processes and the followup. Suggestions for improvement of the current Hungarian practice and other related issues as forensic medicine, media connections, regulations, and reimbursement are also detailed. The guidance has been in agreement with the related medical disciplines.

Metabolic Parameters as Predictors for Progression Free and Overall Survival of Patients with Metastatic Colorectal Cancer.

We tested the prognostic relevance of metabolic parameters and their relative changes in patients with metastatic colorectal cancer (mCRC) treated with monoclonal antibody and chemotherapy. SUVmax (standardized uptake volume), SAM (standardized added metabolic activity) and TLG (total lesion glycolysis) are assessed with 18F-fluorodeoxyglucosepositron emission tomography and computed tomography (FDG-PET/CT) to evaluate total metabolic activity of malignant processes. Our purpose was to investigate the change of glucose metabolism in relation to PFS (progression free survival) and OS (overall survival). Fifty-three patients with mCRC with at least one measurable liver metastasis were included in this prospective, multi-center, early exploratory study. All patients were treated with first-line chemotherapy and targeted therapy. Metabolic parameters, like SUVmax, SAM, normalized SAM (NSAM) and TLG were assessed by FDG-PET/CT, carried out at baseline (scan-1) and after two therapeutic cycle (scan-2). Our results suggested neither SUVmax nor TLG have such prognostic value as NSAM in liver metastases of colorectal cancer. The parameters after the two cycles of chemotherapy proved to be better predictors of the clinical outcome. NSAM after two cycles of treatment has a statistically significant predictive value on OS, while SAM was predictive to the PFS. The follow up normalized SAM after 2 cycles of first line oncotherapy was demonstrated to be useful as prognostic biomarkers for OS in metastatic colorectal cancer. We should introduce this measurement in metastatic colorectal cancer if there is at least one metastasis in the liver.

[PET-based measurements in oncology: PET/CT and PET/MRI applications]. / PET-alapú mérések az onkológiában: PET/CT és PET/MR alkalmazások.

The introduction and clinical application of 2-deoxy-2-[fluorine- 18]fluoro-D-glucose (18F-FDG) Positron Emission Tomography/Computed Tomography (PET/CT) dates back more than two decades. The method has resulted in a paradigm shift in many areas of oncology and its acceptance has grown very rapidly. The state-of-the-art PET-based hybrid measurement, PET/Magnetic Resonance Imaging (PET/ MRI), has been available since 2011 and offers additional invaluable opportunities. Various recommendations have been made to provide guidance for the standardization and harmonization of PET/MRI protocols and to support the application of the method in clinical use and research. Hopefully, with well-defined professional indications, similar to PET/CT applications, the PET/MRI technology, still somewhat mystified today, will soon become part of our everyday lives.

[Oncology PET radiopharmaceuticals in clinic and research in 2020]. / 2020 onkológiai PET-radiogyógyszerei a klinikumban és a kutatásban.

"PET based" molecular imaging has significant role in personalized medicine. New radiopharmaceuticals are continuously introduced into the daily practice of detecting diseases and assessing the effectiveness of therapy. In recent years theragnostic applications have come to the forefront of radiopharmaceutical development. This article discusses, among others, radiopharmaceuticals labelled with 18F and 68Ga isotopes required for the diagnosis of neuroendocrine and prostate tumours, furthermore the inhibitors of the fibroblast activation protein. The increasing variety of metallic radioisotopes (44Sc, 64Cu, 52Mn, 86Y, 89Zr) will help meet the need for new biomarkers and will greatly facilitate the introduction of the new generation of PET radiopharmaceuticals.

[Molecular imaging of Alzheimer's disease]. / Az Alzheimer-kór molekuláris képi megjelenítése.

The ever-growing average age of the society significantly increases the occurrence of Alzheimer's disease. The increased prevalence represents considerable social and economic burden, which urges the development of diagnostic and therapeutic methods in the field. The most common cause of dementia is Alzheimer's disease, the typical histopathological abnormality of which are well known. The detection of functional changes results in the early diagnosis of the disease, which precedes the morphological changes by years. Positron-emission tomography plays an important role in the demonstration of metabolic changes. The glucose metabolic pattern differs significantly in each clinical form of dementia. The most important ß-amyloid-binding radiopharmaceuticals that should be highlighted are [11C]Pittsburgh compound B that is widely used in the research and [18F]florbetapir that is commonly approved in diagnostics. Tracers visualising neurofibrillary tangles consisting of tau protein appeared most recently. The development continues; newer and newer radiopharmaceuticals appear. These tracers play an important role in both the research and the diagnostics. Orv Hetil. 2019; 160(33): 1289-1295.

Advantages of 18F FDG-PET/CT over Conventional Staging for Sarcoma Patients.

The effective management of patients with sarcomas requires accurate diagnosis and staging. Imaging, such as ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI) are the most freqently used methods for the detection of the lesion location, size, morphology and structural changes to adjacent tissues; however, these modalities provide little information about tumour biology. MRI is a robust and useful modality in tumour staging of sarcomas, however metabolic-fluorodeoxyglucose positron emission tomography/ computer tomography (18F-FDG PET/CT) provides greater accuracy to overall staging in combination with MRI [1]. The advantages of 18F-FDG PET/CT method compared with CT and MRI is that it provides a whole body imaging, maps the viability of the tumour or the metabolic activity of the tissue. Additionally, PET detects the most agressive part of the tumour, demonstrates the biological behaviour of the tumour and therefore has a predictive value. Little data ara available on the role of 18F-FDG PET/CT in the management of sarcomas. The present manuscript aims to provide a review of the major indications of 18F-FDG PET/CT for diagnosis, staging, restaging and monitoring response to therapy and to compare its usefulness with the conventional imaging modalities in the management of patients with sarcomas.

[Hungarian clinical application opportunities of PET/MR imaging and first experiences]. / A PET/MR képalkotás magyarországi klinikai alkalmazásának lehetoségei, elso tapasztalatai.

Hungary's first and still only multimodality PET/MR device is operating in the Health Center of Kaposvár University. The aim of our review article is to present the current Hungarian PET/MR imaging application opportunities, our available initial experiences with this novel multimodality imaging technique in malignant and non-malignant diseases and further potential targeted clinical fields of use are also addressed. Orv Hetil. 2018; 159(34): 1375-1384.

[Use of imaging methods in the current screening, diagnostics and treatment of breast cancer - Professional guidelines. 3rd Breast Cancer Consensus Meeting]. / A képalkotó vizsgálómódszerek alkalmazása az emlõdaganatok korszerû szûrésében, diagnosztikájában és ellátásában - Szakmai útmutató a III. Emlõrák Konszenzus Konferencia alapján.

Breast radiologists and nuclear medical specialists have refreshed their previous statement text during the 3rd Hungarian Breast Cancer Consensus Meeting. They suggest taking into consideration this actual protocol for the screening, diagnostics and treatment of breast tumors, from now on. This recommendation includes the description of the newest technologies, the recent results of scientific research, as well as the role of imaging methods in the therapeutic processes and the follow-up. Suggestions for improvement of the Hungarian current practice and other related issues as forensic medicine, media connections, regulations, and reimbursement are also detailed. The statement text has been cross-checked with the related medical disciplines.

[New trends and novel possibilities in the management of oncologic patients: clinical uses of PET/MRI]. / Újdonságok és új lehetoségek az onkológiai betegek terápiás vezetésében: PET/MR klinikai alkalmazások.

The most recent multimodality technique, the hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) combines two very different technologies, which is a great result of human creativity. The combined PET/MRI has significant potentials in clinical oncology providing new perspectives of functional and anatomical information. PET/MRI offers simultaneous measurements of multifunctional data such as PET mapping by different specific tracers or MRI morphologic, MR molecular (MR spectroscopy, MRS), or MR functional (fMR) information of a living system.

[New challenges and perspectives in nuclear medicine imaging]. / Újdonságok és új lehetoségek a nukleáris medicina képalkotásban.

Hybrid positron emission tomography/computer tomography (PET/CT) and single photon emission computer tomography/computer tomography (SPECT/CT) have resulted in significant advances both in medical research and routine clinical use. The most recent multimodality system that combines PET and magnetic resonance imaging (MRI) offers new potentials unthinkable before. The hybrid techniques allow obtaining simultaneous morphologic, functional, and molecular information of a living system. The proper use of multimodality imaging is of high importance as they facilitate both basic medical research and clinical practice.

[Clinical application of 18F-FDG PET/CT in the treatment of sarcomas]. / A 18F-FDG PET/CT klinikai alkalmazása és lehetõségei a sarcomák kezelésében.

[18F]-Fluoro-deoxyglucose positron emission tomography / computer tomography (18F-FDG PET/CT) is able to detect and assess the abnormal metabolism, enabling visualization and quantification in vivo with integration into CT anatomic information. The clinical usefulness of FDG PET/CT in the management of patients with sarcomas has been assessed by numerous investigators. Sarcomas are solid malignant tumors with distinct clinical and pathological features. Effective management of patients with sarcoma requires accurate diagnosis and staging. The authors discuss the major indications of PET/CT on the basis of literature data for diagnosis, staging, guidance of biopsy and monitoring response to therapy in both primary bone and soft tissue tumors. The consistent use of PET molecular imaging methods is of high importance in characterizing and understanding sarcoma behavior in clinical practice.

[Why is PET/CT essential in urooncology?]. / Miért kell a PET/CT az uroonkológiában?

The wide use of molecular positron emission tomography/computed tomography (PET/CT) imaging in the tumor diagnostics has been playing an important role recently. The clinical role of hybrid imaging (PET/CT, single photon ECT/CT (SPECT/CT)) is growing continuously due to the simultaneous imaging of anatomy and function. Regarding oncology the role of (18)F-fluorodeoxyglucose ((18)F-FDG) PET is proved in several clinical questions, including urooncology. Urologic cancers are associated with low or slightly significant uptake of FDG, due to their more benign behaviour. However, alternative PET tracers have been developed which show promising clinical results and hopefully, in the near future the combination of different tracers are awaited. Additionally, in the future the use of multiparametric measurements, multitracer techniques, and the multimodal PET/magnetic resonance imaging (PET/MRI) technology is going to have a crucial clinical role.

[Clinical use of 18F-FDG PET/CT in colorectal carcinoma]. / 18F-FDG PET/CT klinikai alkalmazása colorectalis carcinomában.

Modern imaging techniques have an important role in the diagnostic procedures of malignancies, and assessing response to therapy. The 18F-FDG PET/CT revolutionized the evaluation of colorectal cancer in terms of preoperative staging and monitoring of recurrence. Conventional imaging techniques have limitations in early assessment of response to therapy. 18F-FDG PET has been shown to allow earlier treatment monitoring, because the metabolic change appears before any anatomic change occurs. The Response Evaluation Criteria in Solid Tumours (RECIST) are widely applied, but they have some limitations. There are new international guidelines for treatment response assessment using PET/CT in solid tumours. The authors review indications and the role of hybrid PET/CT in colorectal cancer.

[The role of PET-CT in detecting unknown primary tumour in patients with cervical lymph node metastases]. / A PET-CT szerepe az ismeretlen primer tumorok kimutatásában manifeszt nyaki áttétes betegek esetében.

PET-CT examination was conducted with 440 patients treated at the Department of Head and Neck Surgery, National Institute of Oncology, Budapest, between January 1, 2006 and December 31, 2010. Out of them 77 patients were selected with whom no examination of any sort (physical, pan-endoscopy, or any of the conventional imaging techniques) succeeded in identifying the primary tumour. In each case the primary examination (aspiration cytology and histology) verified cervical metastases, most of them being squamous cell carcinoma. The significance of PET-CT was retrospectively evaluated in cases of unknown primary tumour with verified cervical metastases. We tested the sensitivity of PET-CT in detection of the primary malignant tumour, and possible distant metastases or a second primary in order to plan an optimal treatment schedule for the patient. Patients with whom the examinations specified in the treatment protocol (physical examination, pan-endoscopy, conventional imaging, biopsy) had failed to diagnose the primary tumour were referred to PET-CT. In each case 18F-FDG tracer was used. In 21/77 patients (27%), the PET-CT yielded unequivocal evidence for the primary tumour confirmed by histology, as well. With 10 others (13%), the precarious diagnoses by various imaging techniques were confirmed by the PET-CT. False positive findings with PET-CT that were not verified either by histology or control examination tests occurred but in 10 patients (13%). Concerning the primary tumour, false negative result was obtained only with 3 patients (4%). It should be noted that their retrospective evaluation proved diagnostic errors, the primary tumours were visible in all the scans. With 33 patients (43%) PET-CT furnished no additional information compared to the previous examinations. In 10 patients, asymptomatic distant metastases and in 3 patients synchronous tumours were diagnosed. We also acknowledge that the significance of PET-CT using 18F-FDG is unquestionable in the detection of unknown primary tumours. It is strongly recommended to re-include the detection of unknown primaries in the approved national indication list of PET-CT. (Note, until January 1, 2008 it had been included!) PET-CT is capable of detecting a primary tumour, after all unsuccessful diagnostic examinations till then, in 25-40% of the cases. One cannot disregard the role and significance of PET-CT in the detection of asymptomatic synchronous tumours, or distant metastases. These benefits make PET-CT a suitable tool for the refinement of individually tailored treatment strategies leading to better therapeutic results and more favourable cost-benefit ratio.