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Medullary thyroid carcinoma (MTC) is one of the most challenging cancers. Epidemiological studies have shown that during the past 30 years neither a change in stage at diagnosis nor a significant improvement in survival has been achieved. Therefore, new diagnostic and therapeutic strategies are needed for early detection of metastases or disease recurrence and tumor growth control.

Introduction The aim of this study was to assess the utility of [Lys40(Ahx-HYNIC-99mTc/EDDA)NH2]-exendin-4 scintigraphy in the management of patients with hypoglycemia, particularly in the detection of occult insulinoma. Materials and Methods Forty patients with hypoglycemia and increased/confusing results of serum insulin and C-peptide concentration and negative/inconclusive results of other imaging examinations were enrolled in the study. In all patients GLP-1 receptor imaging was performed to localise potential pancreatic lesions. Results Positive results of GLP-1 scintigraphy were observed in 28 patients. In 18 patients postsurgical histopathological examination confirmed diagnosis of insulinoma. Two patients had contraindications to the surgery, one patient did not want to be operated. One patient, who presented with postprandial hypoglycemia, with positive result of GLP-1 imaging was not qualified for surgery and is in the observational group. Eight patients were lost for follow up, among them 6 patients with positive GLP-1 scintigraphy result. One patient with negative scintigraphy was diagnosed with malignant insulinoma. In two patients with negative scintigraphy Munchausen syndrome was diagnosed (patients were taking insulin). Other seven patients with negative results of 99mTcGLP-1 scintigraphy and postprandial hypoglycemia with C-peptide and insulin levels within the limits of normal ranges are in the observational group. We would like to mention that 99mTc-GLP1-SPECT/CT was also performed in 3 pts with nesidioblastosis (revealing diffuse tracer uptake in two and a focal lesion in one case) and in two patients with malignant insulinoma (with the a focal uptake in the localization of a removed pancreatic headin one case and negative GLP-1 1 scintigraphy in the other patient). Conclusions 99mTc-GLP1-SPECT/CT could be helpful examination in the management of patients with hypoglycemia enabling proper localization of the pancreatic lesion and effective surgical treatment. This imaging technique may eliminate the need to perform invasive procedures in case of occult insulinoma.

This study aimed to investigate the level of the eye lens (EL) doses in nuclear medicine in the light of the new International Commission on Radiological Protection limit. In 7 Belgian and 1 Polish hospitals, 45 staff members were monitored for EL (Hp(3)) and whole-body (WB) (Hp(10)) doses using dedicated dosemeters. Weekly measurements were carried out and used to estimate annual doses. Mostly diagnostic procedures involving radionuclides such as (99m)Tc and (18)F were monitored; measurements were also performed for therapeutic procedures. The cumulative doses showed important variation across the participants. The weekly EL and WB doses ranged from 0.02 to 0.27 and 0.03 to 0.17 mSv, respectively; the annual EL and WB doses ranged from 0.6 to 9.3 and 0.9 to 8.0 mSv, respectively. Some correlation was found between the EL and the WB doses. No significant correlation with the manipulated activities was found.

Mammography provides early micro-calcification recognition, that is important for further breast cancer (BC) diagnosis. Imaging choice for BC detection is X-ray mammography (MG) with the use of high-resolution digital modality combined with iodinated contrast agents. However, a conventional MG has some sensitivity limitations, especially in patients with densely treated breasts. Moreover, MG contributes radiation risk for BC that is correlated with an exposure to ionizing radiation. Patients, for whom MG study does not give a clear interpretation are often further diagnosed by contrast-enhanced breast MRI, the most sensitive BC detection technique. Alternatively, it is limited by higher costs, lower availability and increased false positives. Dual-energy contrast-enhanced spectral mammography (CESM) is a new method applied in BC that enables accurate detection of malignant breast lesions similar to breast MRI. The aim of this study was to compare the usefulness of CESM versus MG in BC detection. Additionally, doses given to the BC patients during imaging were compared. In this study, 250 consecutive women (144 MG vs. 105 CESM), that were screened using mammography between 2011 and 2014 were retrospectively enrolled in the study. The comparison of entrance surface air kerma and mean glandular dose values for both options were recorded, respectively and analyzed using different statistical and retrospective approach. Results of presented study showed that CESM might be a new diagnostic tool allowing an accurate detection of BC lesions, giving results similar to those received from magnetic resonance imaging. A good agreement found between sensitivity of the method and tumour diameters measurements based on CESM, supports this tool as a potential replacement for breast MRI in the preoperative evaluation of BC patients. However, a radiation burden for patients might be significantly higher than that for a standard full-field digital mammography procedure. In summary, each method has its own benefits with respect to specific applications that are further discussed in the study. Citation Format: Kamila Rawojc, Kamil Kisielewicz, Anna Dziecichowicz, Monika Tomaszuk, Anna Cepiga, Jankowska Anna, Cieśla Izabela, Najberg Dominika, Luczynska Elzbieta, Bartosz Kieltyka. Exposure burden for patients during an experimental study using a dual-energy contrast-enhanced spectral mammography [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3742. doi:10.1158/1538-7445.AM2017-3742

One of the major procedures for testing the geometrical accuracy of devices used in radiotherapy treatments is the test of the geometrical position of the radiation isocenter. The importance of the test reflects the fact that geometrical position of the radiation isocenter generally affects the tumor targeting. At present the geometric accuracy is assessed with the Winston-Lutz test which checks the position of an image of a ball marker with the respect to the center of the radiation field as projected on a detector plane. Obviously, determination of coordinates of a single marker is not sufficient to fully account for a complicated geometry of a therapeutic device. The purpose of the study was to design a new image analysis tool to better determine the isocenter. The proposed automated procedure for determining isocenter position uses projection data acquired for a special cube phantom. The projection images of a phantom are acquired for various angles of rotation of the gantry. A procedure is proposed to extract some geometric characteristics of a therapeutic device from the projection images.