Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) comprise a heterogeneous group of neoplasms, which derive from cells of the diffuse neuroendocrine system that specializes in producing hormones and neuropeptides and arise in most cases sporadically and, to a lesser extent, in the context of complex genetic syndromes. Furthermore, they are primarily nonfunctioning, while, in the case of insulinomas, gastrinomas, glucagonomas, vipomas, and somatostatinomas, they produce hormones responsible for clinical syndromes. The GEP-NEN tumor grade and cell differentiation may result in different clinical behaviors and prognoses, with grade one (G1) and grade two (G2) neuroendocrine tumors showing a more favorable outcome than grade three (G3) NET and neuroendocrine carcinoma. Two critical issues should be considered in the NEN diagnostic workup: first, the need to identify the presence of the tumor, and, second, to define the primary site and evaluate regional and distant metastases. Indeed, the primary site, stage, grade, and function are prognostic factors that the radiologist should evaluate to guide prognosis and management. The correct diagnostic management of the patient includes a combination of morphological and functional evaluations. Concerning morphological evaluations, according to the consensus guidelines of the European Neuroendocrine Tumor Society (ENETS), computed tomography (CT) with a contrast medium is recommended. Contrast-enhanced magnetic resonance imaging (MRI), including diffusion-weighted imaging (DWI), is usually indicated for use to evaluate the liver, pancreas, brain, and bones. Ultrasonography (US) is often helpful in the initial diagnosis of liver metastases, and contrast-enhanced ultrasound (CEUS) can solve problems in characterizing the liver, as this tool can guide the biopsy of liver lesions. In addition, intraoperative ultrasound is an effective tool during surgical procedures. Positron emission tomography (PET-CT) with FDG for nonfunctioning lesions and somatostatin analogs for functional lesions are very useful for identifying and evaluating metabolic receptors. The detection of heterogeneity in somatostatin receptor (SSTR) expression is also crucial for treatment decision making. In this narrative review, we have described the role of morphological and functional imaging tools in the assessment of GEP-NENs according to current major guidelines.

Objective: The aim of this study was to assess the added diagnostic value of contrast-enhanced CT (CECT) as compared to unenhanced CT (UECT) in PET/CT staging and treatment response assessment of ¹⁸FDG-avid lymphomas. Methods: 170 PET/UECT followed by CECT scans were prospectively performed for staging (n = 85) and for treatment response assessment (n = 85) of ¹⁸FDG-avid lymphomas, during a single session using an integrated 64-slice PET/CT scanner. CECT and UECT images were evaluated separately by two radiologists, whereas PET images by two nuclear physicians. Nodal and extranodal UECT and CECT findings were classified according to the Lugano criteria, and successively compared with PET/CT results, considered the gold standard. In the analysed groups, the agreement rate with the disease status determined via PET was calculated separately for UECT and CECT using Mc Nemar’s test on paired data. The added value of the contrast medium was shown by the agreement between the PET and CECT results and the lack of agreement between UECT and PET. Results: CECT enabled the identification of additional extranodal lesions (hepatic, muscular and gastric) in only 3 staging group cases (3.5%), indicating different stages as compared to UECT, whereas there was absolute agreement between CECT and UECT in terms of treatment response assessment. The added diagnostic value of CECT was lower than the established threshold for clinical relevance (15%). Mc Nemar’s test indicated no statistical significance in either group. The incidental findings detected by CECT but not UECT were important for clinical management, but not sufficient to alter lymphoma treatment strategy. Conclusion: According to our results, it might be possible to exclude CECT examination of ¹⁸FDG-avid lymphoma from staging and treatment response assessment, with the consequent advantages of reducing radiation exposure and potential contrast-related risks.

Neuroendocrine neoplasms (NENs) are a group of lesions originating from cells of the diffuse neuroendocrine system. NENs may involve different sites, including the gastrointestinal tract (GEP-NENs). The incidence and prevalence of GEP-NENs has been constantly rising thanks to the increased diagnostic power of imaging and immuno–histochemistry. Despite the plethora of biochemical markers and imaging techniques, the prognosis and therapeutic choice in GEP-NENs still represents a challenge, mainly due to the great heterogeneity in terms of tumor lesions and clinical behavior. The concept that biomedical images contain information about tissue heterogeneity and pathological processes invisible to the human eye is now well established. From this substrate comes the idea of radiomics. Computational analysis has achieved promising results in several oncological settings, and the use of radiomics in different types of GEP-NENs is growing in the field of research, yet with conflicting results. The aim of this narrative review is to provide a comprehensive update on the role of radiomics on GEP-NEN management, focusing on the main clinical aspects analyzed by most existing reports: predicting tumor grade, distinguishing NET from other tumors, and prognosis assessment.

Purpose: The workload of the radiology department (RD) of a university hospital in northern Italy dramatically changed during the COVID-19 outbreak. The restrictive measures of the COVID-19 pandemic lockdown influenced the use of radiological services and particularly in the emergency department (ED). Methods: Data on diagnostic services from March 2020 to May 2020 were retrospectively collected and analysed in aggregate form and compared with those of the same timeframe in the previous year. Data were sorted by patient type in the following categories: inpatients, outpatients, and ED patients; the latter divided in “traumatic” and “not traumatic” cases. Results: Compared to 2019, 6449 fewer patients (−32.6%) were assisted in the RD. This decrease was more pronounced for the emergency radiology unit (ERU) (−41%) compared to the general radiology unit (−25.7%). The proportion of investigations performed for trauma appeared to decrease significantly from 14.8% to 12.5% during the COVID-19 emergency (p < 0.001). Similarly, the proportion of assisted traumatic patients decreased from 16.6% to 12.5% (p < 0.001). The number of emergency patients assisted by the RD was significantly reduced from 45% during routine activity to 39.4% in the COVID-19 outbreak (p < 0.001). Conclusion: The COVID-19 outbreak had a tremendous impact on all radiology activities. We documented a drastic reduction in total imaging volume compared to 2019 because of both the pandemic and the lockdown. In this context, investigations performed for trauma showed a substantial decrease.

In the staging of cancer patients, transient and spontaneously reversible bilateral adrenal hypertrophy may mimic a secondary localization of the disease. We discuss the case of an 82-year-old male patient with suspected testicular neoplasia in which abdominal CT examination reveals the onset of a bilateral macronodular adrenal enlargement, suggesting the diagnostic hypothesis of primary testicular neoplasia with secondary adrenal localization. The subsequent ¹⁸FDG-PET/CT study showed hyper-metabolism of the testicular mass, while the adrenal glands, surprisingly, did not show increased uptake of the radiotracer. After right orchifunicolectomy, primary testicular diffuse large B-cell lymphoma was diagnosed. The subsequent staging PET/CT study with iodine contrast medium, three months after the first CT examination, showed spontaneous complete regression of the adrenal hypertrophy without any use of drug therapy. The differential diagnosis of this finding considered the lack of hypermetabolism and the densitometric characteristics of the adrenal glands, the absence of possible pharmacological interactions throughout the time of the diagnostic procedures, and the available clinical-laboratory data. By excluding the main causes of adrenal hypertrophy, the most likely diagnostic hypothesis was transient adrenal hypertrophy due to stress induced by testicular lymphoma, meaning by stress a disturbance not only emotional but also an alteration of organic homeostasis. Our case suggests that the analysis of adrenal lesions appeared in cancer patients should take into account non-metastatic conditions that must be studied with a multimodal approach and with serial investigations.