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The Neutron Star Low-Mass X-ray Binary Swift J1749.4-2807 is the only known eclipsing Accreting Millisecond X-ray Pulsar. On March 2021, the source underwent a short (11-days) and relatively faint outburst, reaching a X-ray luminosity at the peak of only 2×1036erg s−1. We present the first ever broadband spectral characterization of the system throughout the whole outburst, analyzing 11 NICER observations and XMM-Newton and NuSTAR single observations. This is also one of the very few times that, thanks to NICER, we had the opportunity to follow an X-ray binary outburst in its entirety in the soft X-ray band. According to our analysis, no direct emission from the disc was found (perhaps due to it being too cool), and the the broadband spectrum is well-modelled with a black body component, most likely emitted by a hot spot on the Neutron Star surface, and a Comptonization spectrum arising from a hot electron corona. A moderate truncation radius for the disc, i.e. at ∼20-30 R𝐺, was obtained from the analysis of the smeared profile of the Fe line in the reflection component. The significant detection of a blue-shifted Fe XXVI absorption line at ∼7 keV indicates weakly relativistic disk winds. The discovery of such outflows, typically observed in the soft state of X-ray binaries, is unexpected as the spectral properties of the systems are consistent with a hard-intermediate state. This finding could in principle suggest magnetic propeller-driven winds. In the last few years, a pattern of winds in AMXPs out of the canonical soft states seems to have emerged. However, such detections are typically unconstrained and/or weakly significant, as AMXPs display generally faint outbursts when compared to the other X-ray binaries, due to the state-of-the-art technology. With Athena we will be not only to confirm the existence of such outflows, but to investigate their origin.

Nuclear medicine in NENs covers a pivotal role, both in diagnostics and in therapy, outlining the concept of theragnostic approach, bases on radiopharmaceuticals. The whole theme is based on the overexpression of somatostatin receptors (SSTRs), membrane molecule that allow the feasibility of this techniques, mediating the interaction between the drug and the targeted neoplastic cells, in order to depict it or to kill it, depending on the radiopharmaceutical’s purpose: this molecular background will be the main focus of this paper, from native somatostatin and receptors to the concept of internalization. Today, the gold standard in nuclear medicine in this context is represented by 68GaDOTA-peptides in association with PET/CT, but other important techniques and radiotracers will also be presented. Finally, some clinical condition, in which these techniques are employed, will be presented, such as GEP-NETs, lung NETs, unknown primary NETs (CUP lesions) and metastases.

Theragnostics is not a new conception, even if nowadays it is gaining more and more importance in clinical practice and interest among researchers, thanks to their great results obtained in oncologic (especially in neuroendocrine tumors) and non-oncologic fields, too. A theragnostic approach is synthesizable in “see what you treat and treat what you see”, in other words a strategy that has the goal to be in between diagnostics and therapy. Theragnostics is founded on functional and biological characteristics of diseases, on which is based radiopharmaceuticals’ development, there is to say very specific drugs able to bind a precise target and labeled to a particular radionuclide, that is specifically chosen depending on its diagnostic or therapeutic purpose. In this paper, the Authors will focus the attention on several current and promising future application of theragnostics in several clinical scenarios, starting from neuroendocrine tumors (one of the most active sectors in this field), differentiated thyroid carcinoma, neuroblastoma and pheochromocytoma/paraganglioma, castration-resistant prostatic cancer, liver neoplastic lesions (metastases and/or hepatocellular carcinoma) through SIRT/TARE locoregional techniques.

Prostate cancer (PCa) provides different types of approach, both as regards the diagnostic and therapeutic aspects, based on the stage of disease. Nowadays, multi-parametric MRI (mpMRI) plays a pivotal role in primary prostate cancer diagnosis and opens the door to the planning of therapeutic st In this fields, conventional morphological imaging showed limited accuracy for assessment of biochemical recurrent prostate cancer (BRPCa), advanced disease and post-therapy monitoring and evaluations. Nuclear medicine has a metabolic or receptor point of view that is often helpful in situations where morphological analysis is not enough. Radiolabeled choline (11C or 18F), base its use on the exalted neoplastic cell membranes turnover and phosphatidylcholine production increase. Thanks to its features, 68Ga-PSMA PET imaging is affirming in entire PCa diagnostic scenario: from local recurrence and advanced disease to primary tumor localization and lymph nodes disease detection; up to the most future-oriented applications that include radio guided surgery (RGS) and theranostics with 177Lu-PSMA. Having achieved excellent levels of diagnostic accuracy does not stop nuclear medicine research which for these comparison scenarios today also proposes the use of 11C-acetate and 18-Fluciclovine that undermine choline PET/CT and PSMA PET/CT results, in a race for the best possible diagnostic performance. Nuclear medicine is also very active in the study of “bone scenario”, it represent an essential evaluation for correct defining the disease stage. As for diagnostics, also in the therapy’s field we observe the flowering of new solutions, to try to improve both the survival and the quality of life of the patient: 223Ra-dichloride and 177Lu-PSMA are two of the most brilliant examples. Finally, the look towards the future cannot ignore the advent of hybrid systems; from this point of view the diamond shining in the near future undoubtedly seems to be PET/MRI, fixing the maximum anatomical definition with finest metabolic-receptor informations.

Conventional wireless chargers typically utilize a traditional architecture in the receiver to convert RF signals to dc power, which includes rectification of the resonant current, a dc–dc conversion, and finally a battery charging stage by either a linear or switching regulator. Such implementation requires multiple stages and associated components, while in many new applications, both size and efficiency are critical, and a new solution is required. In this paper, the newly proposed architecture aims at improving both parameters by directly controlling the reactive impedance of the receiver and thus eliminating the dc–dc converter with its associated losses. The whole system can be integrated in a standard 180-nm CMOS process.

The current review aimed to explore the association between urban greenspaces and health indicators. In particular, our aims were to analyze the association between publicly accessible urban greenspaces exposure and two selected health outcomes (objectively measured physical activity (PA) and mental health outcomes (MH)). Two electronic databases—PubMed/Medline and Excerpta Medica dataBASE (EMBASE)—were searched from 1 January 2000 to 30 September 2020. Only articles in English were considered. Out of 356 retrieved articles, a total of 34 papers were included in our review. Of those, 15 assessed the association between urban greenspace and PA and 19 dealt with MH. Almost all the included studies found a positive association between urban greenspace and both PA and MH, while a few demonstrated a non-effect or a negative effect on MH outcomes. However, only guaranteeing access is not enough. Indeed, important elements are maintenance, renovation, closeness to residential areas, planning of interactive activities, and perceived security aspects. Overall, despite some methodological limitations of the included studies, the results have shown almost univocally that urban greenspaces harbour potentially beneficial effects on physical and mental health and well-being.

In this paper, an extensive description of the main characteristics and possible applications of a double-halo metal-oxide-semiconductor (MOS) device is presented. In particular, the details concerning the prototype fabrication through a standard complementary MOS (CMOS) process and the obtained experimental results are reported. Extensive numerical device simulation has been carried out in order to deeply understand the new structure. Furthermore, to gain insight on the device behavior, an electrical model to be used in SPICE-like circuit simulation tools has been developed and verified. As shown by our analysis, digital integrated circuits employing the new technology introduce, with respect to standard CMOS ones, a drastic reduction of both the device number and the parasitic capacitances, leading to a significant improvement of the circuit performance.

The effect of the passivation layer dielectric constant and T-gate geometry on the performance of millimeter-wave high-power GaN HEMTs is investigated through a nanoscale carrier dynamics description obtained by full-band cellular Monte Carlo simulation. The effective gate length is found to be increased by fringing capacitances and enhanced by the dielectric constant of the passivation layer in the regions adjacent to the gate for layers thicker than about 5 nm. Detailed simulation results are shown for the carrier energy, velocity, scattering, and electric field profiles along the channel. The output impedance under small- and large-signal operations is also discussed. Our results indicate that the effect of the passivation layer dielectric constant changes the nanoscale carrier dynamics and can strongly affect the radio-frequency performance of deep submicrometer devices.

A high-frequency a high-power GaN HEMT was analyzed using our full band Cellular Monte Carlo (CMC) simulator, in order to extract small signal parameters and figures of merit, and to correlate them to carrier dynamics and distribution inside the device. A complete RF and DC characterization of the device was performed using experimental data to calibrate the few adjustable parameters of the simulator. Then, gate-related capacitances, such as Cg, Cgd, and Cgs, were directly and indirectly extracted combining small-signal analysis and DC characterization.

A novel field-effect device for high-density inte- grated circuits has been developed and manufactured. Numerical device simulations have also been carried out in order to deeply investigate the new structure. Such field-effect device is able to perform simultaneously the functions of two traditional field- effect transistors (e.g. a nMOS and a pMOS), working as one or as the other according to the voltage applied to the gate ter- minal. Combinational and sequential circuits employing the new technology introduce, with respect to the standard CMOS ones, a drastic reduction of both required devices number and associated parasitic capacitances. This leads to a significant increase of the circuit speed. Furthermore, the IC circuits obtained with these novel devices are fully compatible with standard CMOS technology and fabrication processes.

This letter reports an extensive analysis of the charge capture transients induced by OFF-state bias in double heterostructure AlGaN/GaN MIS- high electron mobility transistor grown on silicon substrate. The exposure to OFF-state bias induces a significant increase in the ON-resistance (R on ) of the devices. Thanks to time-resolved on-the-fly analysis of the trapping kinetics, we demonstrate the following relevant results: 1) R on -increase is temperature- and field-dependent, hence can significantly limit the dynamic performance of the devices at relatively high-voltage and high temperature (100 °C-140 °C) operative conditions; 2) the comparison between OFF-state and back-gating stress indicates that the major contribution to the R on -increase is due to the trapping of electrons in the buffer, and not at the surface; 3) the observed exponential kinetics suggests the involvement of point-defects, featuring thermally activated capture cross section; and 4) trapping-rate is correlated with buffer vertical leakage-current and is almost independent to gate-drain length.

We compare the performance of GaN HEMT devices based on the established Ga-face technology and the emerging N-face technology. Starting from a state-of-the-art N-face device, we obtain the analogous Ga-face layout imposing the constraint of the same channel charge in both structures, and then, we simulate both the configurations with our full-band cellular Monte Carlo simulator, which includes the full details of the band structure and the phonon spectra. Moreover, we define a modeling approach based on gate-to-2-D electron gas distance and capacitance discussions, which allows a fair comparison between the N- and Ga-face technologies. Full direct current and RF simulations were performed and compared with available experimental data for the N-face device in order to calibrate the few adjustable simulator parameters. Our simulations indicate that N-face GaN HEMTs exhibit improved RF performance with respect to Ga-face devices. Furthermore, the use of an AlN layer in N-face devices results in a reduced alloy scattering and offers a strong back-barrier electron confinement to mitigate short-channel effects, thus improving the cutoff frequency for highly scaled devices.

This paper aims to investigate the potential of the emerging N-face technology with respect to both the direct current and radio frequency performance of GaN high electron mobility transistor (HEMT) devices. High-frequency high-power state-of-the-art HEMTs were investigated with our full-band cellular Monte Carlo simulator, which includes the full details of the band structure and the phonon spectra. A complete characterization of these devices was performed using experimental data to calibrate the few adjustable parameters of the simulator. The effect of scaling the device dimensions, such as the gate length and the access region lengths, on the device performance was analyzed. In addition, the enhancement-mode configuration of the N-face structure was investigated. Our simulations showed that N-face devices represent an important step in engineering HEMT devices for delivering high power density and efficiency at microwave and millimeter-wave frequencies.

Here we report simulation results for high-frequency, high-power state-of-the-art GaN High Electron Mobility Transistors (HEMTs), using a full band Cellular Monte Carlo simulator, which includes the full details of the band structure and the phonon spectra, in order to study the RF performance of the new promising technology available nowadays. A complete characterization of an InGaN back – barrier device has been performed using experimental data to calibrate the few adjustable parameters of the simulator. Furthermore, a study on a device structure based on the N-face configuration was performed. Finally, threading dislocation effects on HEMT device transport properties were investigated (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This brief aims to show the effects of threading edge dislocations on the DC and RF performance of GaN high-electron mobility transistor (HEMT) devices. A state-of-the-art high-frequency and high-power HEMT was investigated with our full-band cellular Monte Carlo (CMC) simulator, which includes the full details of the band structure and the phonon spectra. A complete characterization of the device has been performed using experimental data to calibrate the few adjustable parameters of the simulator. Thermal simulations were also carried out with commercial software in order to operate the corrections needed to model thermal effects. The approach of Weimann based on the results of Read, Bonch-Bruevich and Glasko, and Po?do?r was then used to model with our CMC code the dislocation effects on the transport properties of HEMT devices. Our simulations indicate that GaN HEMT performance exhibits a fairly large dependence on the density of thread dislocation defects. Furthermore, we show that a threshold concentration exists, above which a complete degradation of the device operation occurs.

This paper presents an extensive analysis of the off-state conduction mechanisms in AlGaN/GaN Meta–Insulator–Semiconductor (MIS) transistors. Based on combined bi-dimensional numerical simulation and experimental measurements, we demonstrate the following relevant results: (i) under off-state bias conditions, the drain current can show a significant increase when the drain bias is swept up to 600 V; (ii) several mechanisms can be responsible for off-state current conduction, including band-to-band tunneling and impact ionization; (iii) two-dimensional numerical simulations indicate that band-to-band tunneling plays a major role, while impact ionization does not significantly contribute to the overall leakage. Temperature-dependent I–V measurements were also carried out to identify the origin of the vertical drain-bulk leakage.

A multifunctional field-effect transistor (FET) for the manufacturing of high-density integrated circuits (ICs) has been developed and fabricated. Furthermore, an extensive numerical device simulation campaign has been carried out in order to characterize the new structure. Such device is a metal-oxide-semiconductor (MOS) FET that simultaneously performs the functions of two traditional FETs (an n-channel MOS and a p-channel MOS), working as one or as the other according to the voltage applied to the gate's terminal. Combinational and sequential circuits employing the new technology introduce, with respect to the standard complementary MOS (CMOS) ones, a drastic reduction of both the required device number and the parasitic capacitances. This leads to a significant increase in the circuit's speed. Furthermore, the ICs obtained with these transistors are fully compatible with the standard CMOS technology and fabrication process.

Breakdown mechanisms in AlGaN/GaN HEMT devices are here analyzed, placing particular emphasis in the analysis of GaN based device grown on silicon substrate. Based on combined experimental data and bi-dimensional numerical simulation we demonstrate that many physical mechanisms can contribute to increase the leakage current leading to the final breakdown of the device. In particular we show how band-to-band phenomena, rather than impact ionization, can be responsible of the premature breakdown even in double-heterostructure HEMTs.

A method for incorporating 2D quantum mechanical effects into a full-band Cellular Monte Carlo simulator is described and applied to the simulation of Quantum Well Field Effect Transistors (QWFETs). Incorporating all relevant scattering mechanisms, good agreement is obtained between simulation and experiment in the case of a device with an InGaAs channel. The effect of scaling the QW width is also investigated.

We report the simulation of the large-signal performance of mm-wave FET power amplifiers obtained for the first time through Full Band Monte Carlo particle-based device simulation self-consistently coupled with a Harmonic Balance (HB) frequency domain circuit solver. Due to the iterative nature of the HB algorithm, this FET simulation approach is possible only due to the computational efficiency of our Cellular Monte Carlo (CMC), which uses pre-computed scattering tables. On the other hand, a frequency domain circuit solver such as HB allows the simulation of the steady-state behavior of an external passive reactive network without the need for simulating long transient time (i.e. RC, L/C time constants) typical of time domain solutions. By exploiting this newly developed self-consistent CMC/HB code, we were able to time-efficiently characterize the mm-wave power performance of a state-of-the-art 30-nm gate-length InAlN/GaN HEMT.

We report for the first time the simulation of the large-signal dynamic load-line of high-Q matched mm-wave power amplifiers obtained through a Monte Carlo particle-based device simulator. Due to the long transient time of large reactive circuit elements, the time-domain solution of power amplifier high-Q matching networks requires prohibitive simulation time for the already time-consuming Monte Carlo technique. However, by emulating the high-Q matching network and the load impedance through an active load-line, we show that, in combination with our fast Cellular Monte Carlo algorithm, particle-based accurate device simulations of the large signal operations of AlGaN/GaN HEMTS are possible in a time-effective manner. Reliability issues and parasitic elements (such as dislocations and contact resistance) are also taken into account by, respectively, exploiting the accurate carrier dynamics description of the Monte Carlo technique and self-consistently coupling a Finite Difference Time Domain network solver with our device simulator code.

We provide design guidelines for InGaAs HEMT nanoscale scaling from the analysis of results obtained through our full band Cellular Monte Carlo simulator. In particular, improved RF performance can be obtained preserving a minimum aspect ratio of 5, limiting in such way short channel effects and reducing the electron transit time through the reduction of the effective gate length. Further improvement can be obtained reducing the source-gate access region length. Thus, the effective gate length relative increase and the parasitic intrinsic access region resistance are found to be the main factors limiting nanoscale scaling in THz InGaAs HEMTs.

We report a comparison between state-of-the-art GaN and InGaAs HEMTs in terms of the minimum aspect ratio required to limit short-channel effects. DC and RF simulations were carried out through our full-band cellular Monte Carlo simulator, which includes the full details of the band structure and the phonon spectra. Our results indicate that the minimum aspect ratio for GaN devices is 15 for negligible short-channel effects and 10 for reduced short-channel effects. On the other hand, InGaAs devices perform well for lower aspect ratio values such as 7.5 and 4-5 for negligible and reduced effects, respectively. The origin of this difference between GaN and InGaAs HEMTs is believed to be related to the different dielectric constants of the two materials and the corresponding difference in the electric field distributions related to short-channel effects.

Quantum well field effect transistors have been proposed as promising device candidates for future high-speed and low-power logic applications due to their high electron mobility. This paper aims to study InAs and InGaAs state-of-the-art QWFETs, investigating both RF and DC performance through our full band Cellular Monte Carlo simulator, which includes the full details of the band structure and the phonon spectra. A complete characterization of these devices has been performed using experimental data to calibrate the simulation parameters.

An investigation of RF short-channel effects in state-of-the-art GaN and InGaAs HEMTs, in relation to effective gate length and aspect ratio, is performed through our full band Cellular Monte Carlo simulator. In particular, the short-circuit current gain cut-off frequency, f T , is extracted using two different methods for several gate lengths. The first method relates f T to the electron transit time in the gate region, and from the electron velocity profile allows a direct estimation of f T , the effective gate length L eff , and the investigation of the nananoscale carrier dynamics in the channel. The second extraction methods derives f T through small-signal analysis. Our results indicates that the increasing difference between effective gate length and metallurgical gate length, as the device is scaled, plays a major role in limiting the RF performance. Moreover, maintaining a minimum aspect ratio of 5 for InGaAs HEMTs, and 10 for GaN devices, helps mitigating the short-channel effects.

Here we discuss how Monte Carlo Simulations can be exploited to investigate reliability issues in GaN high electron mobility transistor (HEMT) devices. In particular, we report simulation results for high-frequency, high-power state-of-the-art GaN HEMTs focusing our analysis on the effects of that threading edge dislocations on the DC and RF performance of state of the art technologies. A complete characterization of an InGaN back - barrier device has been performed, and the influence of disclocation density on device performance analyzed.. Furthermore, a device structure based on the N-face configuration is analyzed.

Buffer traps can induce “false” surface-trap signatures in AlGaN-GaN HEMTs, namely the same type of current-mode DLTS peaks and pulse responses that are generally attributed to surface traps. Device simulations are adopted to clarify the underlying physics. Being aware of the above phenomenon is important for both reliability testing and device optimization, as it can lead to erroneous identification of the degradation mechanism, thus resulting in inappropriate correction actions on the technological process.

A new silicon controlled rectifier low voltage triggered (SCR-LVT), to be adopted as protection structure against electrostatic discharge (ESD) events, has been developed and characterized. A high holding voltage has been obtained thanks to the insertion of two parasitic bipolar transistors, achieved adding a n-buried region to a conventional SCR structure. These two parasitic transistors partially destroy the loop feedback gain of the two main npn and pnp BJTs, resulting in an increase of the sustaining (holding) voltage during the ESD event. A strong dependence of the holding voltage with the ESD pulse width has also been observed, caused by self-heating effects. 2D device simulations (DESSIS Synopsys) have been performed obtaining results that perfectly fit the measurements over a wide temperature range (25 degC-125 degC). Using device simulation results , the factors that influence the holding voltage, in terms of temperature dependence, but also in the behavior of the parasitic BJTs, are explained. A guideline to change the SCR holding voltage, related to the SCR design layout without any change to process parameters, is also proposed.

We have developed and analyzed two alternative devices for the manufacture of high-density ICs, each of which is a FET that develop contemporarily the function of two classical transistors, allowing notably advantages in the realization of SRAM and logic circuits. We tested the effective functionality of these devices through Synopsys TCAD tools. We also extracted for each one of these a full set of electrical equations.

A new silicon-controlled rectifier low voltage triggered (SCR-LVT), to be adopted as protection structure against electrostatic discharge (ESD) events, has been developed and characterized. A high holding voltage has been obtained thanks to the insertion of two parasitic bipolar transistors, achieved adding a n-buried region to a conventional SCR structure. These two parasitic transistors partially destroy the loop feedback gain of the two main npn and pnp BJTs, resulting in an increase of the sustaining (holding) voltage during the ESD event. A strong dependence of the holding voltage with the ESD pulse width has also been observed, caused by self-heating effects. 2D-device simulations (DESSIS Synopsys) have been performed obtaining results that perfectly fit the measurements over a wide temperature range (25 °C − 125 °C). Using device simulation results, the factors that influence the holding voltage, in terms of temperature dependence, but also in the behavior of the parasitic BJTs, are explained. A guideline to change the SCR holding voltage, related to the SCR design layout without any change to process parameters, is also proposed.

The effects of polarization charge on the electrostatic potential distribution across the heterostructure of a AlGaN/GaN high electron mobility transistor device have been investigated. Simulations were performed using a full-band cellular Monte Carlo simulator, which included electronic dispersion and the phonon spectra. Quantum effects were taken into account using the effective potential method. Experimental extraction of potential profiles across the device was carried out using off-axis electron holography. Based on comparison to simulations, the differences between the theoretical predictions and experimental results could be explained, thereby providing better understanding of device operation.

The most important metrics for the high-frequency and high-power performance of microwave transistors are the cut-off frequency fT, and the Johnson figure of merit FoMJohnson. We have simulated a state-of-the-art, high-frequency and high-power GaN HEMT using our full band Cellular Monte Carlo (CMC) simulator, in order to study the RF performance and compare different methods to obtain such metrics. The current gain as a function of the frequency, was so obtained both by the Fourier decomposition (FD) method and the analytical formula proposed by Akis. A cut-off frequency fT of 150 GHz was found in both the transit time analysis given by the analytical approach, and the transient Fourier analysis, which matches well with the 153 GHz value measured experimentally. Furthermore, through some physical considerations, we derived the relation between the FoMJohnson as a function of the breakdown voltage, VBD, and the cut-off frequency, fT . Using this relation and assuming a breakdown voltage of 80V as measured experimentally, a Johnson figure of merit of around 20 × 1012V/s was found for the HEMT device analyzed in this work.

Anatomopathological classification of Neuroendocrine tumors (NETs), today, covers a pivotal role in correctly identifying the disease and establish the right diagnostic and therapeutic approach it is needed in order to manage the patient. Depending on its grading and staging, NENs can have very different prognostic perspectives. Basing on WHO 2017 classification, in this paper will be explored their main characteristics, diving into main histotypes, dividing them into functional and non-functional tumors, keeping in mind their main locations: gastroenteropancreatic tract and lungs. Their typical clinical presentation and diagnostic strategies will be explained, mainly focusing on nuclear medicine and the importance of receptor overexpression (especially represented by somatostatin receptors, or SSTRs). This is the knowledge on which is based the diagnostic and therapeutic approach with peptide radiopharmaceuticals, especially 68Ga-DOTA-peptides (today, the gold standard in well-differentiated neuroendocrine neoplasms, only with the exception of insulinoma, that shows a low density of these molecules on its cellular surface).

Diagnostics and therapy in neuroendocrine tumors (NETs) has been heavily influenced by nuclear medicine progresses, both from a diagnostic and therapeutic perspective. The introduction of somatostatin-based peptides, labeled to radionuclides (constituting radiopharmaceuticals), such as the current golden standard 68Ga-DOTA-SSAs (SomatoStatin Analogues), has revolutionized the approach to these neoplasms. Peptides-based drugs in NENs’ management have been introduced with OctreoScan® (111In-DTPA-octreotide) in combination with scintigraphy, but today techniques have deeply evolved, allowing better performance together with higher accuracy and sensitivity, in addition to image quality improvements (also in terms of details and anatomical data), especially thanks to the implementation of hybrid techniques, such as SPECT/CT and PET/CT. 68Ga-based radiotracers are not the only diagnostic option in NENs, because of the existence of several tumors (such as insulinomas or malignant neoplasms) that do not express SSAs’ target molecules, thus the utilization of other radiocompunds is needed, such as 18F-FDG.

Prostate cancer (PCa) is considered a major challenge for the many medical disciplines that deal with it; despite the diagnostic and therapeutic improvement, it remains for male sex the most common neoplasm and one of the major causes of death. Clinical presentation is classically varied and can change in relation to the disease state. The diagnostic suspicion must trigger some evaluations by a team of specialists: both biochemical and clinical. To date, despite the galaxy of new diagnostic technologies available, the first steps are still being conducted on the track that sees a central role of serum PSA levels and digito-rectal exploration (DRE). Currently an increasingly emerging role in this field is occupied by MRI, so much so that we can speak of an MRI-targeted biopsy (MRI-TB); in fact, through various methods of use, we try to improve the quality of the samples in order to have more and more accurate biopsies focused on the disease areas. The possibility of using increasingly specific sequences such as diffusion-weighted imaging (DWI), dynamic contrast-enhanced imaging (DCE) and MR spectctroscopy (MRS) certainly places it at the center of the diagnostic step of this phase of disease. Also from a therapeutic point of view there have been great steps forward in recent years, for both non-metastatic and metastatic disease. In both the diagnostic and therapeutic fields, alongside conventional radiological and pharmacological techniques, nuclear medicine is in a very useful position. In an increasingly targeted approach and in an increasingly “precise” medicine, radiopharmaceuticals such as Ra-223 dichloride and 177Lu-PSMA represent the new frontiers of prostate cancer treatment.

Diagnostics and therapy in neuroendocrine tumors (NETs) has been heavily influenced by nuclear medicine progresses, both from a diagnostic and therapeutic perspective. The introduction of somatostatin-based peptides, labeled to radionuclides (constituting radiopharmaceuticals), such as the current golden standard 68Ga-DOTA-SSAs (SomatoStatin Analogues), has revolutionized the approach to these neoplasms. That is not all: these radiopharmaceuticals have been employed also into a therapeutic context, realizing the so-called PRRT (peptide receptor radionuclide therapy), allowing NENs to be integrated into a comprehensive theragnostic approach, making advantage of the knowledge based on receptor overexpression of neuroendocrine tumors, in particular SSTRs (somatostatin receptors). PRRT is mainly focused on the utilization of 90Y-and 177Lu-based peptides, but in this case another important factor is needed: the internalization process, a pivotal phenomenon that allows the efficacy of the therapy, thanks to the intracellular collection of radioisotopes: in this way, they are able to damage internal structures of neoplastic cells.