ABSTRACT
Recent research has suggested that one novel mechanism of action for anti-obesity medications is to stimulate the activation of brown adipose tissue (BAT). 18FDG PET/CT remains the gold standard for defining and quantifying BAT. SUVmax is the most often used quantification tool in clinical practice. However, this parameter does not reflect the entire BAT volume. As a potential method for precisely evaluating BAT, we have utilised metabolic tumour volume (MTV) and total lesion glycolysis (TLG) to answer the question: Are MTV and TLG accurate in quantifying the intensity of BAT activation? After analysing the total number of oncological 18F-FDG PET/CT scans between 2021-2023, we selected patients with active BAT. Based on the BAT SUVmax, the patients were divided into BAT-moderate activation (MA) vs. BAT-high activation (HA). Furthermore, we statistically analysed the accuracy of TLG and MTV in assessing BAT activation intensity. The results showed that both parameters increased their predictive value regarding BAT activation, and presented a significantly high sensitivity and specificity for the correct classification of BAT activation intensity. To conclude, these parameters could be important indicators with increased accuracy for classifying BAT expression, and could bring additional information about the volume of BAT to complement the limitations of the SUVmax.
ABSTRACT
The high energy of α emitters, and the strong linear energy transfer that goes along with it, lead to very efficient cell killing through DNA damage. Moreover, the degree of oxygenation and the cell cycle state have no impact on these effects. Therefore, α radioisotopes can offer a treatment choice to individuals who are not responding to ß- or gamma-radiation therapy or chemotherapy drugs. Only a few α-particle emitters are suitable for targeted alpha therapy (TAT) and clinical applications. The majority of available clinical research involves 225Ac and its daughter nuclide 213Bi. Additionally, the 225Ac disintegration cascade generates γ decays that can be used in single-photon emission computed tomography (SPECT) imaging, expanding the potential theranostic applications in nuclear medicine. Despite the growing interest in applying 225Ac, the restricted global accessibility of this radioisotope makes it difficult to conduct extensive clinical trials for many radiopharmaceutical candidates. To boost the availability of 225Ac, along with its clinical and potential theranostic applications, this review attempts to highlight the fundamental physical properties of this α-particle-emitting isotope, as well as its existing and possible production methods.
ABSTRACT
Brown Adipose Tissue (BAT) is considered beneficial in diabetes and obesity, but it can also have negative effects such as its implication in tumours' pathogenesis and the development of Cancer-induced Cachexia. Since 18F-FDG PET/CT is a common molecular imaging modality used in cancer assessment, we aim to study the 18F-FDG BAT biodistribution in oncological patients and look for possible correlations between BAT activity and different malignancies as well as the patient's weight status. After analysing the total number of oncological 18F-FDG PET/CT scans between 2017 and 2021, we selected patients with active BAT. Based on their BMI, the selected patients were divided into nonobese (NO) vs. overweight and obese (OOB). OOB SUVmaxlean body mass(LBM) had the highest mean values in supraclavicular, latero-cervical, and paravertebral vs. mediastinal and latero-thoracic localisations in NO. BMI was positively correlated with latero-cervical and supraclavicular SUVmax(LBM) but negatively correlated with latero-thoracic and abdominal SUVmax(LBM). Considering the age of the patients, SUVmax(LBM) decreases in the latero-cervical, paravertebral, and abdominal regions. In addition, the males presented lower SUVmax(LBM) values. SUVmax(LBM) was not affected by the treatment strategy or the oncological diagnosis. To conclude, it is mandatory to take into consideration the BAT particularities and effects on weight status in order to optimise the clinical management of oncological patients.
ABSTRACT
Gastrin-secreting tumors, hypergastrinemia and severe ulcer disease form the trademarks of Zollinger-Ellison syndrome (ZES). We report a case of gastrinoma, in a patient who was misdiagnosed for almost five years. The case emphsizes the the special role of functional imaging in the personalized approach to the patient with suggestive symptomatology for NETs. Taking into account that in 80 to 100% of cases of gastroenteropancreatic (GEP) NETs are expressing somatostatin receptors, the functional imaging with radiolabeled somatostatin analogues can be used in order to improve its diagnosis, respectively the treatment of GEP NETs. In the approach to the patient with tremendous digestive symptomatology, physicians from different specialties should evaluate NETs specific markers and then insist on structural-functional complementarity, avoiding the waste of time and high cost of repeated structural investigations. The conclusion of our study is that functional imaging is mandatory in the diagnostic algorithm of gastrinoma.