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Background: Transarterial Radioembolisation (TARE) requires multidisciplinary experience and skill to be effective. The aim of this study was to identify determinants of survival in patients with hepatocellular carcinoma (HCC), focusing on learning curves, technical advancements, patient selection and subsequent therapies. Methods: From 2005 to 2020, 253 patients were treated. TARE results achieved in an initial period (2005–2011) were compared to those obtained in a more recent period (2012–2020). To isolate the effect of the treatment period, differences between the two periods were balanced using “entropy balance”. Results: Of the 253 patients, 68 were treated before 2012 and 185 after 2012. In the second period, patients had an Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) score of 1 (p = 0.025) less frequently, less liver involvement (p = 0.006) and a lesser degree of vascular invasion (p = 0.019). The median overall survival (OS) of patients treated before 2012 was 11.2 months and that of patients treated beginning in 2012 was 25.7 months. After reweighting to isolate the effect of the treatment period, the median OS of patients before 2012 increased to 16 months. Conclusions: Better patient selection, refinement of technique and adoption of personalised dosimetry improved survival after TARE. Conversely, sorafenib after TARE did not impact life expectancy.

PURPOSE: Recently, a new Bayesian Penalized Likelihood (BPL) Reconstruction Algorithm was introduced by GE Healthcare, Q.Clear; it promises to provide better PET image resolution compared to the widely used Ordered Subset Expectation Maximization (OSEM). The aim of this study is to compare the performance of these two algorithms on several types of findings, in terms of image quality, lesion detectability, sensitivity, and specificity. METHODS: Between September 6th 2017 and July 31st 2018, 663 whole body 18F-FDG PET/CT scans were performed at the Nuclear Medicine Department of S. Martino Hospital (Belluno, Italy). Based on the availability of clinical/radiological follow-up data, 240 scans were retrospectively reviewed. For each scan, a hypermetabolic finding was selected, reporting both for OSEM and Q.Clear: SUVmax and SUVmean values of the finding, the liver and the background close to the finding; size of the finding; percentage variations of SUVmax and SUVmean. Each finding was subsequently correlated with clinical and radiological follow-up, to define its benign/malignant nature. RESULTS: Overall, Q.Clear improved the SUV values in each scan, especially in small findings (

Background Graft selection strategy in living donor liver transplantation (LDLT) is usually multifactorial, but special attention is paid to the determination of donor liver volumes to minimize any risk of posthepatectomy liver failure (PHLF). Hepatobiliary scintigraphy (HBS) with single-photon-emission computed tomography allows for the measurement of total and future liver remnant function (FLR-F) and has been shown to predict the risk of PHLF more accurately than liver volumetry. Methods Since November 2016, HBS has been performed at our Institution in every candidate to major hepatectomy, including potential living liver donors. Results Thirty-seven consecutive patients were submitted to HBS, of whom 7 were potential living liver donors. After completed hepatectomy (n = 27), the median FLR-F of patients who developed PHLF (n = 9) was 1.72%/min/m2 (range 1.40–2.78) compared to that of patients who did not (n = 18), which was 4.02%/min/m2 (range 1.15–12.08). Three donors underwent operations (1 right hepatectomy and 2 left hepatectomies). In the only donor who developed PHLF, the FLR accounted for the 37% of the total liver volume, whereas the FLR represented only the 31% of the total liver function (TL-F = 11.29%/min) with a resulting FLR-F of 2.05%/min/m2. Conclusions The present study suggests that a non-invasive low-cost exam such as HBS may be a promising tool to predict PHLF not only in neoplastic patients but also to evaluate potential living donors. Larger studies are needed to draw any conclusion regarding the benefits of HBS in the living liver donor workup.

Purpose A multidisciplinary expert panel convened to formulate state-of-the-art recommendations for optimisation of selective internal radiation therapy (SIRT) with yttrium-90 ( 90 Y)-resin microspheres. Methods A steering committee of 23 international experts representing all participating specialties formulated recommendations for SIRT with 90 Y-resin microspheres activity prescription and post-treatment dosimetry, based on literature searches and the responses to a 61-question survey that was completed by 43 leading experts (including the steering committee members). The survey was validated by the steering committee and completed anonymously. In a face-to-face meeting, the results of the survey were presented and discussed. Recommendations were derived and level of agreement defined (strong agreement ≥ 80%, moderate agreement 50%–79%, no agreement ≤ 49%). Results Forty-seven recommendations were established, including guidance such as a multidisciplinary team should define treatment strategy and therapeutic intent (strong agreement); 3D imaging with CT and an angiography with cone-beam-CT, if available, and 99m Tc-MAA SPECT/CT are recommended for extrahepatic/intrahepatic deposition assessment, treatment field definition and calculation of the 90 Y-resin microspheres activity needed (moderate/strong agreement). A personalised approach, using dosimetry (partition model and/or voxel-based) is recommended for activity prescription, when either whole liver or selective, non-ablative or ablative SIRT is planned (strong agreement). A mean absorbed dose to non-tumoural liver of 40 Gy or less is considered safe (strong agreement). A minimum mean target-absorbed dose to tumour of 100–120 Gy is recommended for hepatocellular carcinoma, liver metastatic colorectal cancer and cholangiocarcinoma (moderate/strong agreement). Post-SIRT imaging for treatment verification with 90 Y-PET/CT is recommended (strong agreement). Post-SIRT dosimetry is also recommended (strong agreement). Conclusion Practitioners are encouraged to work towards adoption of these recommendations., info:eu-repo/semantics/published

Hepatobiliary scintigraphy (HBS) has been demonstrated to predict post-hepatectomy liver failure (PHLF). However, existing cutoff values for future liver remnant function (FLR-F) were previously set according to the “50–50 criteria” PHLF definition. Methods of calculation and fields of application in liver surgery have changed in the meantime. The aim of this study was to demonstrate the role of HBS combined with single photon emission computed tomography (SPECT/CT) in predicting severity of PHLF, according to the International Study Group of Liver Surgery (ISGLS). All patients submitted to major hepatectomy with preoperative HBS-SPECT/CT between November 2016 and December 2019, were analyzed. Patients were resected according to hepatic volumetry. Receiver operating characteristic (ROC) curve analysis was performed to identify cutoffs of FLR function for predicting PHLF according to ISGLS definition and grading. Of the 38 patients enrolled, 26 were submitted to one-stage hepatectomy (living liver donors = 4) and 12 to two-stage procedures (portal vein embolization = 4, ALPPS = 8). Overall, 18 patients developed PHLF according to ISGLS criteria: 12 of grade A (no change in the patient’s clinical management) and 6 of grade B (change in clinical management). ROC analysis established increasingly higher cutoffs of FLR-F for predicting PHLF according to the “50–50 criteria”, ISGLS grade B and ISGLS grade A/B, respectively. HBS with SPECT/CT may help to assess severity of PHLF following major hepatectomy. Prospective multicenter trials are needed to confirm the effective role of HBS-SPECT/CT in liver surgery. Electronic supplementary material The online version of this article (10.1007/s13304-020-00907-2) contains supplementary material, which is available to authorized users.

Purpose: To describe cerebral glucose metabolism pattern as assessed by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in Lafora disease (LD), a rare, lethal form of progressive myoclonus epilepsy caused by biallelic mutations in EPM2A or NHLRC1. Methods: We retrospectively included patients with genetically confirmed LD who underwent FDG-PET scan referred to three Italian epilepsy centers. FDG-PET images were evaluated both visually and using SPM12 software. Subgroup analysis was performed on the basis of genetic and clinical features employing SPM. Moreover, we performed a systematic literature review of LD cases that underwent FDG-PET assessment. Results: Eight Italian patients (3M/5F, 3 EPM2A/5 NHLRC1) underwent FDG-PET examination after a mean of 6 years from disease onset (range 1-12 years). All patients showed bilateral hypometabolic areas, more diffuse and pronounced in advanced disease stages. Most frequently, the hypometabolic regions were the temporal (8/8), parietal (7/8), and frontal lobes (7/8), as well as the thalamus (6/8). In three cases, the FDG-PET repeated after a mean of 17 months (range 7-36 months) showed a metabolic worsening compared with the baseline examination. The SPM subgroup analysis found no significant differences based on genetics, whereas it showed a more significant temporoparietal hypometabolism in patients with visual symptoms compared with those without. In nine additional cases identified from eight publications, FDG-PET showed heterogeneous findings, ranging from diffusely decreased cerebral glucose metabolism to unremarkable examinations in two cases. Conclusions: FDG-PET seems highly sensitive to evaluate LD at any stage and may correlate with disease progression. Areas of decreased glucose metabolism in LD are extensive, often involving multiple cortical and subcortical regions, with thalamus, temporal, frontal, and parietal lobes being the most severely affected. Prospective longitudinal collaborative studies are needed to validate our findings.

Alterations of the cardiac autonomic nervous system play an important role in the pathway of many heart diseases. Nuclear imaging tools have been demonstrated to be useful for global and regional assessment of myocardial innervation. We used 11 C-meta-hydroxy-ephedrine ( 11 C-mHED), a catecholamine analogue, as a radiotracer usable with a PET/CT scanner to study the cardiac sympathetic system. After a fast and automatic synthesis of mHED and its labeling with 11 C, we acquired cardiac images by using a PET/ CT scanner. In this paper we present our preliminary results showing the radiotracer bio-distribution in humans 10 minutes post injection. The present study assesses the feasibility of PET/CT with the radiolabeled catecholamine analogue ( 11 C-mHED) in order to determine sympathetic innervation in the human heart.

Background Unilateral condylar hyperplasia (UCH) of the mandible, or Hypercondylia, is a pathological condition that determines an abnormal growth of the affected condyle. Bone SPECT with Tc99m-diphosphonates is a successful tool in the diagnosis of UCH. EANM guidelines also suggest the use of 18F–NaF PET/CT, though it leads to a higher radiation exposure. Aim As UCH patients are young, we aimed to develop a low dose 18F–Fluoride PET/CT protocol and compare it to a standard injected activity scan, to assess if the image quality remains unchanged. Materials and methods We prospectively enrolled 20 patients (7 males, 13 females, mean age 23.2) with UCH, who underwent 18F–NaF PET/CT to assess the hypercondylia. We administered a low activity of 18F–NaF (2.9 MBq/kg) in 15 patients and a standard activity (5.3 MBq/kg) in 5 patients. Activity range was chosen according to 2015 EANM guidelines. To determine if the scans with low radiotracer activity were “diagnostic” such as those with standard activity, two expert nuclear medicine physicians, unaware of the administered activity, independently reviewed the scans and expressed a final qualitative judgment in terms of “diagnostic”/“non-diagnostic” scan. Furthermore, we compared the effective dose of a low injected activity PET/CT to the standard one and to a Bone SPECT performed with standard injected activity of Tc99m-diphosphonates. Results Reviewers classified 19 of 20 scans as “diagnostic”. Only one of them was classified as “non diagnostic” due to condylar arthrosis that disturbed the correct evaluation of condylar radiotracer uptake. The effective dose of a 18F–Fluoride PET/CT, in patient of 70 kg, is about 3.5 mSv in scans performed with 2.9 MBq/kg [0.017 mSv/MBq × 2.9 MBq/kg × 70 kg] and about 6.3 mSv in ones performed with 5.3 MBq/kg [0.017 mSv/MBq × 5.3 MBq/kg × 70 kg]. The effective dose of 99mTc-MDP bone SPECT is about 3.2 mSv [0.0043 mSv/MBq × 740 MBq of 99mTc-MDP]. Discussion 18F–NaF PET/CT performed with a low radiotracer activity allows a good assessment of UCH similar to that performed with an ordinary activity. The effective radiation dose of a low-injected activity PET/CT is significantly lower than an ordinary-injected activity and is not significantly higher than the most used Bone SPECT. Moreover PET/CT is performed in 1.5 h while Bone SPECT requires at least 3.5 h. Conclusions The 18F–Fluoride PET/CT procedure could be performed with 2.9 MBq/Kg (minimum 185 MBq, recommended at least 200 MBq) of 18F–NaF to minimize the effective radiation dose received, maintaining the quality of the scan. Further studies including a larger number of patients and clinical follow-up are needed to confirm our preliminary findings.

The aim of the study was to assess which factors may influence (11)C-choline PET/CT detection rate in a population of recurrent prostate cancer (PCa) patients listed for salvage radiation therapy (S-RT) in an early phase of biochemical relapse, to select which patients could obtain the most benefit by performing restaging (11)C-choline PET/CT before S-RT. METHODS: The study comprised 605 patients, treated with radical prostatectomy (RP) with curative intent for PCa who showed rising PSA levels after primary therapy and listed for S-RT. Prostate-specific antigen (PSA) values were >0.2 ng/mL and

Aim The aim of this study was to assess the performance of FDG PET/ceCT simultaneously acquired, contemporary read and finally discussed by the radiologist and the nuclear medicine physician for staging and restaging lung cancer patients. Methods We analysed 17 consecutive patients (7F; 10M; mean age 68). Six patients were in staging, 8 patients were in restaging (1 during therapy, 2 after therapy and 5 during the follow-up) and 2 patients needed to characterise a suspect pulmonary mass. All the patients underwent combined FDG PET/CT and ceCT acquired simultaneously on the same tomograph. The images were read and reported together by the nuclear medicine physician and the radiologist. Results None of the patients had adverse reactions nor complained about the procedure. Thirteen FDG PET/ceCT turned out positive, while 4 were completely negative. Among positive patients, a significant SUV max was detected in all the cases (range 1.8–17.5). In the end, 9 patients had a true positive result, 4 true negative, 3 false positive and 1 false negative. Sensitivity, specificity and accuracy of the combined procedure were 90%, 57% and 76% respectively. In 7/17 patients FDG PET/CT and ceCT were completely concordant. FDG PET/CT provided a significant impact on the final interpretation in 7/17 patients while ceCT had a major impact in 3/17 patients. Discussion This preliminary study shows that FDG PET/ceCT is a feasible technique for lung cancer patients, providing an optimal sensitivity (90%). From our results it is advisable not to include patients without an histological diagnosis of cancer due to possible false positivity of the two methods, significantly reducing specificity. However, a proper patient selection is not easy and the future of this combined test relies essentially on the capacity to early identify only the subjects who would really benefit from both the procedures.

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The aims of this work were to explore patient eligibility criteria for dosimetric studies inCalibrations withSensitivity was nearly constant varying activity and distance (maximum s.d.=2%). Partial volume effects were negligible for object area ⩾960mmThe minimum calibration protocol requires sensitivity and transmission curve measurements varying the object size, performing a careful procedure standardisation. Lesions with

Background:Intrahepatic cholangiocarcinoma (ICC) is a rapidly progressing malignancy; only a minority of the tumours can be resected and the palliative regimens have shown limited success. The aim of this study was to assess overall survival (OS), tumour response and the safety of radioembolization with yttrium-90 (90Y-TARE) in patients with unresectable/recurrent ICC.Methods:Survival was calculated from the date of the 90Y-TARE procedure. Target and overall Response Evaluation Criteria in Solid Tumors (RECIST) and modified RECIST (mRECIST) and European Association for the Study of the Liver (EASL)—measuring delayed-phase contrast enhancement—treatment responses were assessed at 3 months.Results:The overall median survival was 17.9 months (95% CI: 14.3–21.4 months). Significantly longer survival was obtained in naive patients as compared with patients in whom TARE was preceded by other treatments, including surgery (52 vs 16 months, P=0.009). Significantly prolonged OS was recorded for patients with a response based on mRECIST and the EASL criteria while RECIST responses were not found to be associated with survival. Treatment was well-tolerated, and no mortality was reported within 30 days.Conclusions:In unresectable ICC, 90Y-TARE is safe and offers a survival benefit in naive patients, as well as in responders.British Journal of Cancer (2016) advance online publication 23 June 2016; doi:10.1038/bjc.2016.191 www.bjcancer.com.

Purpose The aims of this work were to explore patient eligibility criteria for dosimetric studies in 223 Ra therapy and evaluate the effects of differences in gamma camera calibration procedures into activity quantification. Methods Calibrations with 223 Ra were performed with four gamma cameras (3/8-inch crystal) acquiring planar static images with double-peak (82 and 154 keV, 20% wide) and MEGP collimator. The sensitivity was measured in air by varying activity, source-detector distance, and source diameter. Transmission curves were measured for attenuation/scatter correction with the pseudo-extrapolation number method, varying the experimental setup. 223 Ra images of twenty-five patients (69 lesions) were acquired to study the lesions visibility. Univariate ROC analysis was performed considering visible/non visible lesions on 223 Ra images as true positive/true negative group, and using as score value the lesion/soft tissue contrast ratio (CR) derived from 99m Tc-MDP WB scan. Results Sensitivity was nearly constant varying activity and distance (maximum s.d. = 2%). Partial volume effects were negligible for object area ⩾960 mm 2 . Transmission curve measurements are affected by experimental setup and source size, leading to activity quantification errors up to 20%. The ROC analysis yielded an AUC of 0.972 and an optimal threshold of CR of 10, corresponding to an accuracy of 92%. Conclusion The minimum calibration protocol requires sensitivity and transmission curve measurements varying the object size, performing a careful procedure standardisation. Lesions with 99m Tc-MDP CR higher than 10, not overlapping the GI tract, are generally visible on 223 Ra images acquired at 24 h after the administration, and possibly eligible for dosimetric studies.

The performance of a depth-of-interaction preclinical small animal PET scanner (GE eXplore Vista) has been investigated. To this purpose several parameters such as spatial resolution, sensitivity, scatter fraction and noise equivalent counts were measured. Because of the different mean positron range of 18 F and 11 C attention was focused on measuring the effect of such difference on the scanner spatial resolution. The spatial resolution was measured using a point, a line source and a high resolution phantom. Scatter fraction and noise equivalent counts were measured using mouse and rat size objects. Results show that the eXplore Vista provides a spatial resolution of 1.48 mm and sensitivity up to 6%. In vivo images of small mice were also presented.

In recent years, a new PET compound (anti-3-(18)F-FACBC or (18)F-fluciclovine) was tested for the detection of prostate cancer relapse. Despite very promising results, only preliminary data were available with regard to the comparison to (11)C-choline. The aim of this study was to compare the detection rate of (18)F-FACBC and (11)C-choline in patients presenting a biochemical relapse.Fifty patients radically treated for prostate cancer and presenting with rising prostate-specific antigen (PSA) levels were consecutively and prospectively enrolled. All the patients were out of hormonal therapy and underwent both (11)C-choline PET/CT and (18)F-fluciclovine PET/CT within 1 week. The results were compared in terms of detection rate on a patient and lesion basis. Furthermore, a more detailed analysis regarding local, lymph node, and bone relapse was performed.On a patient-based analysis, (18)F-fluciclovine detection turned out to be significantly superior to (11)C-choline (P0.000001). This result was also true on lesion, lymph node, bone lesion, and local relapse analysis (P0.0001 in all the cases). There was no significant difference in terms of target to background of positive lesions between (11)C-choline and (18)F-fluciclovine. When the patients were divided into groups with different PSA levels, (18)F-fluciclovine had a superior detection rate for low, intermediate, and high PSA levels.In our experimental conditions, (18)F-fluciclovine provided a statistically significant better performance in terms of lesion detection rate as compared with (11)C-choline. However, more studies are required to evaluate the clinical significance of these results in terms of sensitivity, specificity, and accuracy.

Purpose: We assessed the rate of detection rate of recurrent prostate cancer by PET/CT using anti-3-18F-FACBC, a new synthetic amino acid, in comparison to that using 11C-choline as part of an ongoing prospective single-centre study. Methods: Included in the study were 15 patients with biochemical relapse after initial radical treatment of prostate cancer. All the patients underwent anti-3-18F-FACBC PET/CT and 11C-choline PET/CT within a 7-day period. The detection rates using the two compounds were determined and the target–to-background ratios (TBR) of each lesion are reported. Results: No adverse reactions to anti-3-18F-FACBC PET/CT were noted. On a patient basis, 11C-choline PET/CT was positive in 3 patients and negative in 12 (detection rate 20 %), and anti-3-18F-FACBC PET/CT was positive in 6 patients and negative in 9 (detection rate 40 %). On a lesion basis, 11C-choline detected 6 lesions (4 bone, 1 lymph node, 1 local relapse), and anti-3-18F-FACBC detected 11 lesions (5 bone, 5 lymph node, 1 local relapse). All 11C-choline-positive lesions were also identified by anti-3-18F-FACBC PET/CT. The TBR of anti-3-18F-FACBC was greater than that of 11C-choline in 8/11 lesions, as were image quality and contrast. Conclusion: Our preliminary results indicate that anti-3-18F-FACBC may be superior to 11C-choline for the identification of disease recurrence in the setting of biochemical failure. Further studies are required to assess efficacy of anti-3-18F-FACBC in a larger series of prostate cancer patients.

Purpose: To investigate and compare the quantitative accuracy of 90Y imaging across different generation PET/CT scanners, for the purpose of dosimetry after radioembolization with resin microspheres. Methods: A strict experimental and imaging protocol was followed by 47 international sites using the NEMA 2007/IEC 2008 PET body phantom with an 8-to-1 sphere-to-background ratio of 90Y solution. The phantom was imaged over a 7-day period (activity ranging from 0.5 to 3.0 GBq) and all reconstructed data were analysed at a core laboratory for consistent processing. Quantitative accuracy was assessed through measures of total phantom activity, activity concentration in background and hot spheres, misplaced counts in a nonradioactive insert, and background variability. Results: Of the 69 scanners assessed, 37 had both time-of-flight (ToF) and resolution recovery (RR) capability. These current generation scanners from GE, Philips and Siemens could reconstruct background concentration measures to within 10 % of true values over the evaluated range, with greater deviations on the Philips systems at low count rates, and demonstrated typical partial volume effects on hot sphere recovery, which dominated spheres of diameter 20 mm in diameter, activity concentrations were consistently underestimated by about 20 %. Non-ToF scanners from GE Healthcare and Siemens were capable of producing accurate measures, but with inferior quantitative recovery compared with ToF systems. Conclusion: Current generation ToF scanners can consistently reconstruct 90Y activity concentrations, but they underestimate activity concentrations in small structures (≤37 mm diameter) within a warm background due to partial volume effects and constraints of the reconstruction algorithm. At the highest count rates investigated, measures of background concentration (about 300 kBq/ml) could be estimated on average to within 1 %, 5 % and 2 % for GE Healthcare (all-pass filter, RR + ToF), Philips (4i8s ToF) and Siemens (2i21s all-pass filter, RR + ToF) ToF systems, respectively. Over the range of activities investigated, comparable performance between GE Healthcare and Siemens ToF systems suggests suitability for quantitative analysis in a scenario analogous to that of postradioembolization imaging for treatment of liver cancer., 0, SCOPUS: ar.j, info:eu-repo/semantics/published

The eye lens annual dose limit for exposed personnel to ionizing radiation has recently been revised by the ICRP - International Commission on Radiological Protection and the proposed new limit has been accepted by European legislation through the Council Directive 2013/59/EURATOM 2013. Among medical exposed personnel, the staff performing interventional cardiology are usually affected by relevant doses. For this reason a survey, employing dosemeters characterized in terms of Hp(3), was performed in order to get the order of magnitude of the doses received by the eye lens, at least as a first guess. The survey showed that the annual dose limit can easily be reached if a proper radiation protection approach is not implemented. © 2015 IOP Publishing Ltd.

Purpose: We analyzed overall survival (OS) following radioembolization according to macroscopic growth pattern (nodular vs infiltrative) and vascular invasion in intermediate–advanced hepatocellular carcinoma (HCC). Methods: Between September 2005 and November 2013, 104 patients (50.0% portal vein thrombosis [PVT], 29.8% infiltrative morphology) were treated. Results: Median OS differed significantly between patients with segmental and lobar or main PVT (p = 0.031), but was 17 months in both those with patent vessels and segmental PVT. Median OS did not differ for infiltrative and nodular HCC. Median OS was prolonged in patients with a treatment response at 3 months (p = 0.023). Prior TACE was also a significant predictor of improved OS. Conclusion: A further indication for radioembolization might be infiltrative HCC, since OS was similar to nodular types.

We investigated the diagnostic accuracy of (99m)Tc-3,3- diphosphono-1,2-propanodicarboxylic acid ((99m)Tc-DPD) scintigraphy for differentiation of monoclonal immunoglobulin light-chain (AL) and transthyretin (TTR)-related cardiac amyloidosis. BACKGROUND: Differential diagnosis between TTR-related and AL amyloidosis is often complex and time-consuming. METHODS: Patients under routine observation with TTR-related/AL systemic amyloidosis and echocardiographic evidence of cardiac involvement were studied with (99m)Tc-DPD scintigraphy. RESULTS: Patients with cardiac involvement of TTR-related (group A; n = 15) and AL (group B; n = 10) etiology were comparable for left ventricular mass and renal function. Heart and heart/whole-body tracer retention were significantly higher (p < 0.05) in group A as compared with group B and with 10 unaffected controls. At visual scoring, cardiac (99m)Tc-DPD uptake was present in all group A patients and absent in all group B patients; thus, using genotyping/immunohistochemistry as the reference technique, the accuracy of (99m)Tc-DPD scintigraphy for distinction of TTR-related and AL etiology was 100%. Cardiac (99m)Tc-DPD uptake was also absent among unaffected controls. Using echocardiography as the reference standard for recognition of cardiac involvement, sensitivity and specificity of scintigraphy were both 100% for group A patients; in group B, sensitivity was 0% and specificity was 100% (accu racy, 50%). Eleven patients with myocardial (99m)Tc-DPD uptake underwent (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) scintigraphy; all patients showed a (99m)Tc-MDP myocardial visual score of 0. CONCLUSIONS: Etiology is a third major cause-in addition to type of organ-involved (soft-tissue/heart) and tracer type-of scintigraphic variability in cardiac amyloidosis. This is a highly relevant consideration for future studies. We conclude that (99m)Tc-DPD scintigraphy is a useful step in the workup of the differential diagnosis of TTR versus AL etiology in patients with documented cardiac amyloidosis.

Objective: The aim of this study was to evaluate the rate of postactinic inflammatory alterations that could lead to false-positive results in FDG-PET images, in a group of lymphoma patients studied with positron emission tomography (PET) early after the end of radiation therapy. Materials and methods: Sixteen (16) consecutive patients were referred to our center for malignant lymphoma; 14 of 16 patients had a mediastinal bulky mass at diagnosis. Each patient underwent chemotherapy and then radiotherapy (RT): for clinical reasons, shortly after RT (range, 25–56 days; mean, 38.7 days) a FDG PET scan was required to evaluate the effect of therapy. We intravenously injected 370 MBq of 18F-FDG, and after 60–90 minutes we recorded images. Results: Despite a relatively short time after RT, there was no pathological tracer uptake in 13 of 16 patients. In 3 cases, a mild increase in FDG uptake was observed, but no findings which would lead to a false-positive diagnosis. In 2 of 3 cases, postactinic pneumopathy wa...

Objectives: To assess the potential association between dopamine transporter (DAT) genotype, single photon emission CT (SPECT) measures using [ 1 2 3 I]-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane ([ 1 2 3 I]-FP-CIT) of striatal dopaminergic function, and oral levodopa response pattern in a cohort of patients with Parkinson disease. Methods: Thirty-six patients at different disease stages enrolled in the study. Each patient was examined by [ 1 2 3 I]-FP-CIT SPECT and a standardized oral levodopa test on 2 separate days in a randomized order within 3 weeks. The main outcome variables were the specific-to-nonspecific tracer uptake ratio in the contralateral putamen for SPECT analysis; latency, duration, and magnitude of the motor effect; and presence of dyskinesias for the levodopa test. The variable number of tandem repeat (VNTR) polymorphisms of the gene coding for DAT were detected for each patient by standard methods. Results: Contralateral putamen [ 1 2 3 I]-FP-CIT uptake ratios were similar in the patients carrying the 9-copy allele (n = 20) of the DAT VNTR compared with 10-repeat homozygotes (n = 16). No significant difference was found in levodopa main outcome variables and dyskinesia incidence between the two groups of patients stratified by DAT VNTR polymorphism. Conclusions: The study did not identify clinically relevant in vivo DAT neurochemical function phenotypes or levodopa response patterns associated with the DAT polymorphism.

BIFFI, M., et al.: Abnormal Cardiac Innervation in Patients with Idiopathic Ventricular Fibrillation.Idiopathic ventricular fibrillation (VF) is diagnosed in up to nearly 10% of survivors of out-of-hospital cardiac arrest. The arrhythmogenic substrate is unknown. This study examined the role of cardiac innervation as a possible contributor to this arrhythmia. Eight patients with idiopathic VF were compared with eight normal subjects (controls) by [123] I metaiodobenzylguanidine SPECT (MIBG), measuring peak uptake, late uptake, and clearance of the nuclear tracer. The left ventricle was divided in 13 segments in the bull's-eye target plot. Peak and late MIBG uptake was increased in the anterolateral segments (2,3,7,8) compared to the inferoposterior and septal segments, in controls and in patients. No difference was observed between controls and patients in the inferoposterior and septal segments. In contrast, a significantly higher MIBG uptake was observed in patients compared to controls in the anterolateral segments (94 ± 4%vs81 ± 11%, P < 0.03for peak uptake;94 ± 5%vs79 ± 12%, P < 0.01for late uptake). No difference was observed in MIBG clearance in any segment in either study group. Cardiac sympathetic innervation is highly heterogeneous, though predominant in anterolateral segments in normal subjects. Patients with idiopathic VF exhibit the same distribution, though have a significantly greater density of sympathetic terminals in the anterolateral segments than controls, which may promote ventricular arrhythmias. (PACE 2003; 26[Pt. II]:357–360)

Purpose: The target lesion response (according to the Choi criteria), safety and survival following selective or superselective transarterial radioembolisation using yttrium-90-resin microspheres (90Y-RE) were evaluated in patients with unresectable, chemotherapy-refractory colorectal cancer liver metastases (mCRC). Materials and methods: A prospective case series evaluated 52 consecutive patients with mCRC who were treated at a single centre following a median of 2 lines of chemotherapy. Results: Nearly half (46.2 %) of the 52 patients had a prior resection of the liver. At baseline, mCRC was limited to the liver (in 56.9 %), liver plus extra-hepatic metastases (23.5 %) or liver plus lung micro-nodules (19.6 %). Disease control rates of target lesions (partial response plus stable disease) at 3 and 6 months post-90Y-RE were 59 and 29 %, respectively. Target lesions were sufficiently downsized in two patients for hepatic resection and in one patient for radiofrequency ablation. Median Kaplan–Meier survival was 11.0 months (95 % confidence interval: 8.0–14.0 months) overall and 12.0 months in liver-only disease (±lung micro-nodules). Determinants of prolonged survival were response at 3 months (P = 0.046), ≤5 liver nodules (P = 0.004), single-liver-lobe involvement (P = 0.037), tumour-to-whole liver ratio 90Y-RE were grade 1 90Y-RE-induced liver disease (n = 1), grade 2 and 3 gastric ulcers (n = 2). Conclusion: These results confirm the effectiveness and safety of selective 90Y-RE in patients with chemotherapy-refractory mCRC, showing 90Y-RE’s potential as a bridging therapy to subsequent resection even in this end-stage population.

Transarterial radioembolization (TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes. On the average, it produces disease control rates exceeding 80% and it is a consolidated therapy for hepatocellular carcinoma (HCC); however, current data are all based on retrospective series or non-controlled prospective studies since randomized controlled trials comparing it with the other liver-directed therapies for intermediate and locally advanced stage HCC are still underway. The data available show that TARE provides similar or even better survival rates when compared to transarterial chemoembolization (TACE). First-line TARE is best indicated for both intermediate-stage patients (staged according to the barcelona clinic liver cancer staging classification) who have lesions which respond poorly to TACE due to multiple tumors or a large tumor burden, and for locally advanced-stage patients with solitary tumors, and segmental or lobar portal vein tumor thrombosis. In addition, emerging data have suggested the use of TARE in patients who are classified slightly beyond the Milan criteria regarding radical treatment for downstaging purposes. As a second-line treatment, TARE can also be applied in patients progressing to TACE or sorafenib; a large number of phase II/III trials are ongoing with the purpose of evaluating the best association with systemic therapies. Transarterial radioembolization is very well tolerated and has a low rate of complications which are mainly related to unintended non-target tissue irradiation, including the surrounding liver parenchyma. The complications can be additionally reduced by accurate patient selection and a strict pre-treatment evaluation including dosimetry and assessment of the vascular anatomy. Since a correct treatment algorithm for potential TARE candidates is not clear and standardized, this comprehensive review analyzes the best selection criteria for patients who really benefit from TARE and also the new advances of this therapy, which can be a very important weapon against HCC.

We developed and validated a Monte-Carlo-based application (RAYDOSE) to generate patient-specific 3D dose maps on the basis of pre-treatment imaging studies. A CT DICOM image is used to model patient geometry, while repeated PET scans are employed to assess radionuclide kinetics and distribution at the voxel level. In this work, we describe the structure of this application and present the tests performed to validate it against reference data and experiments. We used the spheres of a NEMA phantom to calculate S values and total doses. The comparison with reference data from OLINDA/EXM showed an agreement within 2% for a sphere size above 2.8 cm diameter. A custom heterogeneous phantom composed of several layers of Perspex and lung equivalent material was used to compare TLD measurements of gamma radiation from (131)I to Monte Carlo simulations. An agreement within 5% was found. RAYDOSE has been validated against reference data and experimental measurements and can be a useful multi-modality platform for treatment planning and research in MRT.

PURPOSE: Patients treated for ovarian cancer are usually referred for 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (FDG PET/CT) in case of increased Carcinoma Antigen 125 (CA125) but negative conventional imaging. However, there is not enough in the literature to support the value of FDG PET/CT in this context. This study aimed to assess role of FDG PET/CT in a cohort of patients with treated ovarian cancer and correlate the results with serum levels of CA125. PROCEDURES: We retrospectively studied 175 patients, mean age 65.2 years (range 24-88 years) who had radical treatment for ovarian cancer (chemotherapy, surgery or combination). The patients had a standard FDG PET/CT and measurement of serum CA125 within a month of the scan. PET/CT was considered positive if demonstrated areas of abnormally increased metabolic activity unrelated to physiological distribution, on the basis of a visual analysis. The results of PET/CT imaging were compared to the level of CA125, and receiver operating characteristic (ROC) curves were plotted and area-under-the curve (AUC) statistics were computed. Cytologic or histologic data or clinical and imaging follow-up were taken as gold standard. RESULTS: Patients were divided into five groups based on CA125 values. The average level of CA125 was 107.7 (range 3-867, SD 166.1). PET/CT was positive in 125/175 cases (71.4%), mean value of CA125 132.2 (SD 182.9) and negative in 50/175 (28.6%), mean value of CA125 46.4 (SD 89.3). In descriptive ROC analyses, the discriminatory power of this marker was relatively high (AUC statistics 0.77, range = 0.703-0.8). The optimal cut-off point of CA125 after treatment to reflect active disease on PET/CT was 18 U/mL achieving a detection rate of 85.6%. There was no relation between PET/CT negativity and the histological type of the tumor. CONCLUSION: PET/CT was able to detect active disease at relatively low levels of CA125, thereby facilitating the early diagnosis of recurrence or residual disease. Also in patients with low CA125 levels (

Senile systemic amyloidosis (SSA) is a cardiomyopathy mainly affecting elderly men due to intramyocardial deposition of wild-type (nonmutant) transthyretin (TTR) ([1][1]). Since the heart is the only involved organ, SSA—which requires endomyocardial biopsy (EMB) for a definite diagnosis—is often

Objectives: In a cohort of patients with hereditary transthyretin-related amyloidosis (ATTR), we aimed to assess the role of 99mTc-3,3- diphosphono-1,2-propanodicarboxylic acid ( 99mTc-DPD) in detecting myocardial amyloid infiltration across a wide spectrum of cardiac involvement and in predicting major adverse cardiac events (MACE). Background: Hereditary transthyretin-related amyloidosis is a challenging and underdiagnosed condition where both early diagnosis and prognosis remain problematic. Methods: We evaluated 63 patients with ATTR: 40 with and 23 without echocardiographically diagnosed amyloidotic cardiomyopathy (AC). Myocardial uptake of 99mTc-DPD scintigraphy was semiquantitatively and visually assessed at 5 min and 3 h. Results: All patients with AC showed moderate-to-severe myocardial tracer uptake (i.e., visual score 12 mm in combination with H/WB >7.5 was associated with the highest event rate. Conclusions: In ATTR, 99mTc-DPD scintigraphy can identify myocardial infiltration across a wide spectrum of morphologic/functional cardiac involvement, allowing an early diagnosis of the disease (even before the appearance of echocardiographic abnormalities). The 99mTc-DPD myocardial uptake is a prognostic determinant of "cardiac" outcome in ATTR, either alone or in combination with LV wall thickness

TO THE EDITOR: We read with great interest the paper by Ulrich et al. ([1][1]) reporting on the predictive value of 99mTc-macroaggregated albumin (99mTc-MAA) uptake in patients with colorectal liver metastasis scheduled for selective internal radiation therapy (SIRT) with 90Y-loaded resin

Purpose We previously reported in a small series of patients that 99mTc-3, 3-diphosphono-1, 2-propanodicarboxylic acid ( 99mTc-DPD) scintigraphy tested positive in transthyretin-related (TTR) (both mutant and wild-type) but not in primary (AL) amyloidotic cardiomyopathy (AC). We extended our study to a larger cohort of patients with AC. Methods We evaluated (1) 45 patients with TTR-related AC (28 mutant and 17 wild-type), (2) 34 with AL-related AC and (3) 15 non-affected controls. Myocardial uptake of 99mTc-DPD (740 MBq i.v.) was semiquantitatively and visually assessed at 5 min and at 3 h. Results Heart retention (HR) and heart to whole-body retention ratio (H/WB) of late 99mTc-DPD uptake were higher among TTR-related AC (HR 7.8%; H/WB 10.4) compared with both unaffected controls (HR 3.5%; H/WB 5.7; p< 0.0001) and AL-related AC (HR 4.0%; H/WB 6.1; p< 0.0001). For the diagnosis of TTR-related AC, positive and negative predictive accuracy of visual scoring of cardiac retention were: 80 and 100% (visual score ≥1); 88 and 100% (visual score ≥2); and 100 and 68% (visual score = 3). At adjusted linear regression analysis, TTR aetiology turned out to be the only positive predictor of increasing 99mTc-DPD uptake in terms of both HR [β 2.5, 95% confidence interval (CI) 1.5-3.5; p

The aim of this work was to preliminarily evaluate the sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of 68Ga-citrate PET/CT in a population of patients with suspected bone infections. Methods: We enrolled 31 patients with suspected osteomyelitis or diskitis who underwent a total of forty 68Ga-citrate PET/CT scans. The results were compared with different combinations of diagnostic procedures (MRI, radiography, CT, or white blood cell scintigraphy), biopsy (when diagnostic), and follow-up data (at least 1 y) to determine the performance of 68Ga-citrate PET/CT. Results: We found a sensitivity of 100%, a specificity of 76%, a positive predictive value of 85%, a negative predictive value of 100%, and an overall accuracy of 90%. Conclusion: Although preliminary, these data confirm a possible role for 68Ga-citrate in the diagnosis of bone infections, especially in consideration of its favorable characteristics.

Objectives: Antegrade selective cerebral perfusion (ASCP) represents the best method of cerebral protection during surgery of the thoracic aorta. However, brain integrityand metabolism after antegrade cerebralperfusion have not yetbeen investigated. We assessed cerebralpositron emission tomography (PET), diffusion-weighted imaging, proton magnetic resonance spectroscopy and cognitive functions in patients undergoing either ASCP or coronary artery bypass grafting (CABG) to elucidate whether cerebral perfusion was associated with postoperative neuronal alterations, metabolic deficit or cognitive decline. Methods: Seventeen patients undergoing aortic arch surgery using ASCP with moderate hypothermia (26 8C) (ASCP group) and 15 patients undergoing elective on-pump CABG (CABG group) were prospectively enrolled in the study. Brain PET, diffusion-weighted imaging, proton magnetic resonance spectroscopy and neuropsychometric testing were performed preoperatively, and at 1 week and 6 months postoperatively (T1, T2 and T3, respectively). Patient data were compared for statistic analysis with a normal database made up of healthy subjects. Results: One patient in each group was excluded because they refused postoperative evaluation. There were neither strokes nor hospital deaths. Two patients suffered from temporary neurological dysfunction (one in each group). Proton magnetic resonance spectroscopy did not reveal significant alterations in cortical N-acetyl-aspartate (NAA) content within and between the groups at T2 and T3. In the ASCP group, brain diffusion-weighted magnetic resonance showed a significant increase of the apparent diffusion coefficient values, reflecting vasogenic cerebral oedema, at T2, that disappeared at T3. Magnetic resonance detected new focal brain lesions in two CABG group patients. In seven ASCP group patients, PETscan showed glucose hypometabolism in the occipital lobes at T2, which disappeared in five patients at successive examination (T3). Significant cognitive decline was not observed in any patient. Test score changes between and within groups were not significant. Conclusions: There was no evidence of ischaemic brain injury after ASCP even if some degree of reversible brain oedema secondary to cardiopulmonary bypass (CPB) was present. The cognitive outcomes in patients undergoing ASCP were comparable to patients undergoing coronary artery bypass. The lack of left subclavian artery perfusion during cerebral perfusion leads to temporary glucose hypometabolism in the occipital lobes without neuronal injury. # 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Small-animal PET is acquiring importance for pre-clinical studies. In rodents, radiotracers are usually administrated via the tail vein. This procedure can be very difficult and time-consuming as soft tissue extravasations are very frequent and tail scars can prevent repeated injections after initial failure. The aim of our study was to compare the retro-orbital (RO) versus tail vein intravenous (i.v.) administration of (18)F-FDG and (11)C-choline in mice for small-animal PET studies.We evaluated four healthy female ICR CD1 mice according to the following protocol. Day 1: each animal underwent an i.v. injection of 28 MBq of (11)C-choline. PET scan was performed after 10 min and 40 min. Day 2: each animal received an RO injection of 28 MBq of (11)C-choline. A PET scan was performed after 10 min and 40 min. Day 3: each animal received an i.v. injection of 28 MBq of (18)F-FDG. A PET scan was performed after 60 min and 120 min. Day 4: each animal received an RO injection of 28 MBq of (18)F-FDG. A PET scan was performed after 60 min and 120 min. Administration and image acquisition were performed under gas anaesthesia. For FDG studies the animals fasted for 2 h and were kept asleep for 20-30 min after injection, to avoid muscular uptake. Images were reconstructed with 2-D OSEM. For each scan ROIs were drawn on liver, kidneys, lung, brain, heart brown fat and muscles, and the SUV was calculated. We finally compared choline i.v. standard acquisition to choline RO standard acquisition; choline i.v. delayed acquisition to choline RO delayed acquisition; FDG i.v. standard acquisition to FDG RO standard acquisition; FDG i.v. delayed acquisition to FDG RO delayed acquisition.The RO injections for both (18)F-FDG and (11)C-choline were comparable to the intravenous injection of F-FDG for the standard and delayed acquisitions.The RO administration in mice represents a technical advantage over intravenous administration in being an easier and faster procedure. However, its use requires high specific activity while its value in peptides and other receptor-specific radiopharmaceuticals needs further assessment.

Purpose The administration of new anticancer drugs in animal models is the first step from in vitro to in vivo preclinical protocols. At this stage it is crucial to ensure that cells are in the logarithmic phase of growth and to avoid vascular impairment, which can cause inhomogeneous distribution of the drug within the tumour and thus lead to bias in the final analysis of efficacy. In subcutaneous xenograft murine models, positivity for cancer is visually recognisable 2–3 weeks after inoculation, when a certain amount of necrosis is usually already present. The aim of this study was to evaluate the accuracy of FDG small animal PET for the early detection of malignant masses in a xenograft murine model of human rhabdomyosarcoma. A second goal was to analyse the metabolic behaviour of this xenograft tumour over time. Methods We studied 23 nude mice, in which 7×106 rhabdomyosarcoma cells (RH-30 cell line) were injected in the dorsal subcutaneous tissues. Each animal underwent four FDG PET scans (GE, eXplore Vista DR) under gas anaesthesia. The animals were studied 2, 5, 14 and 20 days after inoculation. We administered 20 MBq of FDG via the tail vein. Uptake time was 60 min, and acquisition time, 20 min. Images were reconstructed with OSEM 2D iterative reconstruction and the target to background ratio (TBR) was calculated for each tumour. Normal subcutaneous tissue had a TBR of 0.3. Necrosis was diagnosed when one or more cold areas were present within the mass. All the animals were sacrificed and histology was available to verify PET results. PET results were concordant with the findings of necropsy and histology in all cases. Results The incidence of the tumour was 69.6% (16/23 animals); seven animals did not develop a malignant mass. Ten of the 23 animals had a positive PET scan 2 days after inoculation. Nine of these ten animals developed a tumour; the remaining animal became negative, at the third scan. The positive predictive value of the early PET scan was 90% (9/10 animals) while the negative predictive value was 46% (6/13 animals). In the whole group of animals, mean TBR increased scan by scan. There was a statistically significant difference in TBR between 2 and 20 days after inoculation. Necrosis was present at the second scan in two animals, at the third scan in six animals and at the fourth scan in 11 animals. Conclusion The high positive predictive value of FDG PET 2 days after inoculation means that an animal with a first positive scan has a very high likelihood of developing a mass and can be treated at an early stage with an experimental drug. Animals negative at this point in time will never develop a mass or will eventually do so at a late phase. As 2 of the 16 (12.5%) positive animals had necrosis at the second scan, indicating a vascular mismatch, it may be argued that animals should be treated 2 days after inoculation to guarantee homogeneous vascularisation (thereby ensuring a good drug supply within the tumour) in all subjects.

Background Small-animal imaging has become a relevant research field in pre-clinical oncology. In particular, metabolic information provided by small-animal positron emission tomography (PET) is very useful to closely monitor tumour growth and assess therapy response in murine models of human disease. There are various murine models for human lung adenocarcinoma, but those for squamous cell lung carcinoma, the most common form of human cancer, are lacking. Aim To assess the feasibility of 18F-FDG small-animal PET to monitor tumour growth in a chemically induced model of squamous cell carcinoma of the lung. Materials and methods Nineteen NIH Swiss mice were skin painted by N-nitroso-tris-chloroethylurea (NTCU) twice a week, with a 3 day interval, for 8 months and 10 NIH Swiss mice skin painted with NTCU solvent (acetone) were used as controls. 18F-FDG PET was performed under sevofluorane anaesthesia and oxygen supplementation at 2, 4, 6 and 8 months from initial treatment. Images were assessed by visual analysis and semi-quantitatively. When a diffuse distribution of tumour was noted, the mean of the counts/pixel measured at three lung levels, corrected for the effective dose injected and for decay, was used for comparison between mutagen-painted and control mice. Pathological evaluation was carried out from the time of the first positive PET results in a subgroup of the whole population to assess correlation with PET findings. Small animal CT was performed at 8 months in another subgroup. Results In both terms of visual analysis and measurement of total lung activity, 18F-FDG PET at 2 and 4 months from initial treatment were comparable in mutagen-painted and controls. At 6 months, PET images showed a faint and diffuse uptake over both lung fields in mutagen-painted mice with multiple focal areas of increased tracer uptake that merged into confluent masses at 8 months and seriously subverting lung architecture on computed tomography. Total lung activity was significantly higher in mutagen-painted versus control mice at 6 (P=0.00000668) and 8 months (P=0.00000043) from initial treatment and paralleled the progressive lung involvement and histological severity. Conclusions 18F-FDG PET may be useful in the assessment of this chemically induced murine model of lung squamous cells carcinoma. The total lung activity may be used as a measure of tumour metabolic activity of the tumour-bearing animals and may be useful in new drug testing studies.

Positron emission tomography (PET) is a non-invasive imaging modality, which is clinically widely used both for diagnosis and accessing therapy response in oncology, cardiology and neurology. Fusing PET and CT images in a single dataset would be useful for physicians who could read the functional and the anatomical aspects of a disease in a single shot. The use of fusion software has been replaced in the last few years by integrated PET/CT systems, which combine a PET and a CT scanner in the same gantry. CT images have the double function to correct PET images for attenuation and can fuse with PET for a better visualization and localization of lesions. The use of CT for attenuation correction yields several advantages in terms of accuracy and patient comfort, but can also introduce several artefacts on PET-corrected images. PET/CT image artefacts are due primarily to metallic implants, respiratory motion, use of contrast media and image truncation. This paper reviews different types artefacts and their correction methods. PET/CT improves image quality and image accuracy. However, to avoid possible pitfalls the simultaneous display of both Computed Tomography Attenuation Corrected (CTAC) and non corrected PET images, side by side with CT images is strongly recommended. © 2006 Biomedical Imaging and Intervention Journal. All rights reserved.

The aim of this study was to evaluate the rate of postactinic inflammatory alterations that could lead to false-positive results in FDG-PET images, in a group of lymphoma patients studied with positron emission tomography (PET) early after the end of radiation therapy.Sixteen (16) consecutive patients were referred to our center for malignant lymphoma; 14 of 16 patients had a mediastinal bulky mass at diagnosis. Each patient underwent chemotherapy and then radiotherapy (RT): for clinical reasons, shortly after RT (range, 25-56 days; mean, 38.7 days) a FDG PET scan was required to evaluate the effect of therapy. We intravenously injected 370 MBq of 18F-FDG, and after 60-90 minutes we recorded images.Despite a relatively short time after RT, there was no pathological tracer uptake in 13 of 16 patients. In 3 cases, a mild increase in FDG uptake was observed, but no findings which would lead to a false-positive diagnosis. In 2 of 3 cases, postactinic pneumopathy was diagnosed (PET scan performed 51 and 52 days after RT); while in 1 patient, soft-tissue inflammation was present (PET scan performed 42 days after RT).Our data indicates that the rate of postactinic PET inflammatory alterations in lymphoma patients is not very high and appear to be not strictly linked to the elapsed time since the end of RT treatment.

To evaluate the prevalence and scan interpretation criteria useful in identifying non-tumoural F-FDG focal uptakes (potential pitfalls) in patients who had been previously treated for a malignant lymphoma studied by positron emission tomography (PET).Nine hundred and ninety-six consecutive PET scans obtained in 706 patients with malignant lymphoma were reviewed. All patients had been previously treated by first-line chemo-radiotherapy, plus surgery when required, and were then studied by FDG PET to investigate suspected recurrence at doubtful or inconclusive conventional radiological imaging (ultrasound, computed tomography, magnetic resonance imaging). PET was obtained with patients in the fasted condition and after i.v. injection of 370 MBq of F-FDG; imaging was acquired 60-90 min later. In patients with focal FDG uptake the final diagnosis was reached on the basis of histological findings or long-term follow-up.Thirty-one of 134 PET scans (23.1%) showing focal FDG uptake were diagnosed as non-tumoural radiotracer uptake, related to the presence of brown fat in seven cases, thymic hyperplasia in five, muscles contraction in four, lymph node unspecific inflammation in four, mediastinal/pulmonary unspecific inflammation in four, gastritis in two, colitis in two, bacterial abscess in one, lactating breast in one, and herpes zoster in one. Each of the above cited situations has been reported in the literature, generally in the form of sporadic reports, as a potential cause of misinterpretation (false positive) in reading a PET scan with the potential for incorrect patient management. An accurate diagnosis in these patients was important for the following therapeutic decision making.In the whole series of patients with treated malignant lymphoma, the prevalence of non-tumoural FDG focal uptake during follow-up was relatively low (3.1%); conversely, it was relatively high when considering the sub-group of 'positive' PET only (23.1%). The importance of knowing these situations in order to avoid misinterpretation in reading PET scans needs to be emphasized. In this light, an accurate patient's history and a skilful nuclear medicine physician are very important factors. For the same purpose, it is reasonable to think that the use of hybrid PET/CT tomographs could also play an important role in helping to identify non-tumoural FDG focal uptake.

Malignant Pleural Mesothelioma (MPM) is a relatively rare neoplasia characterized by a poor prognosis. Recent studies show that new therapeutic approaches can lead to an improvement in life quality and to a prolonged survival; therefore, proper evaluation of MPM before, as well as after, therapy, is needed. The aim of this study was to evaluate the impact of 18F-FDG photon emission tomography (PET) scan compared to computed tomography (CT) findings in patients affected by MPM, whether untreated or already treated. We studied 15 consecutive patients (13 male and 2 female) with a histological diagnosis of MPM, with a mean age of 69.9 years (range: 38-78 years old) and a recent total-body CT scan. Five (5) patients were studied for staging, while 10 patients were studied after therapy. An FDG PET scan was carried out 60 minutes after an intravenous (i.v.) injection of 370 MBq of 18F-FDG. For each patient, we compared the PET stage to the CT stage, and evaluated the role of PET in choosing a therapeutic approach. In 9 of 15 (60%) patients, there was no difference between the PET and the CT stage. In 2 of 15 (13%) patients, PET upstaged the disease, while in 4 of 15 (27%) patients PET downstaged MPM. According to these results, patient management was changed in 3 cases. Specifically, 1 patient was excluded from surgery, and 2 patients had different chemotherapy. These data suggest that PET is useful in the evaluation of MPM, giving additional data that can clarify doubtful CT findings, especially regarding lymph node involvement and distant lesions. In conclusion, FDG PET was found to play a worth-while role in patient management.

Levodopa pharmacokinetic-phamacodynamic (PK-PD) modeling may be able to test the functional integrity of the nigrostriatal dopaminergic system in Parkinson's disease (PD). [(123)I]-FP-CIT SPECT imaging of striatal dopamine transporters has also been introduced for the evaluation of presynaptic dopaminergic homeostasis. We aimed to assess the intrapatient relation between levodopa PK-PD and SPECT measures of dopaminergic function in PD. Thirty-five PD patients, 1 to 4 on the Hoehn and Yahr (HY) scale, enrolled in the study. Each patient was examined by levodopa PK-PD modeling and SPECT imaging. Primary measure outcomes were the levodopa half-life in the effect compartment (t1/2(eq)) for PKPD modeling and the ratio of specific to non specific (SP/NSP) tracer striatal uptake for SPECT. Levodopa t1/2(eq) was highly significantly correlated with HY scale (r = -0.815, p0.0001), Unified Parkinson's disease Rating Scale (UPDRS) (r = -0.691, p0.0001) and PD symptom duration (r = -0.647, p0.0001). SPECT contralateral putamen SP/NSP ratio showed the most significant correlations with clinical indicators of disease severity: HY, r = -0.526, p0.002; UPDRS, r = -0.523, p0.002; symptom duration, r = -0.513, p0.002. Significant correlations were observed between levodopa t1/2(eq) and putamen SP/NSP ratios, yielding the closest correlation for the contralateral region (r = 0.522, p0.002). An indirect PK-PD dopaminergic functional variable and direct SPECT measures of presynaptic dopaminergic system homeostasis were in close agreement with clinical data and correlated to each other. Levodopa PK-PD modeling can be a practical clinical tool indirectly assessing the functional integrity of the nigrostriatal dopaminergic system in PD patients.

A selective intra-arterial liver injection using yttrium-90-loaded microspheres as sources for internal radiation therapy is a form of transarterial radioembolization (TARE). Current data from the literature suggest that TARE is effective in hepatocellular carcinoma (HCC) and is associated with a low rate of adverse events; however, they are all based on retrospective series or non-controlled prospective studies, since randomized controlled trials comparing the other liver-directed therapies for intermediate and locally advanced stages HCC are still ongoing. The available data show that TARE provides similar or even better survival rates. TARE is very well tolerated and has a low rate of complications; these complications do not result from the embolic effects but mainly from the unintended irradiation to non-target tissue, including the liver parenchyma. The complications can be further reduced by accurate patient selection and a strict pre-treatment evaluation, including dosimetry and assessment of the vascular anatomy. First-line TARE is best indicated for intermediate-stage patients (according to the Barcelona Clinic Liver Cancer [BCLC] staging classification) who are poor candidates for transarterial chemoembolization or patients having locally advanced disease with segmental or lobar branch portal vein thrombosis. Moreover, data are emerging regarding the use of TARE in patients classified slightly above the criteria for liver transplantation with the purpose of downstaging them. TARE can also be applied as a second-line treatment in patients progressing to transarterial chemoembolization or sorafenib; a large number of Phase II/III trials are in progress in order to evaluate the best association with systemic therapies. Given the complexity of a correct treatment algorithm for potential TARE candidates and the need for clinical guidance, a comprehensive review was carried out analyzing both the best selection criteria of patients who really benefit from TARE and the new advances of this therapy which add significant value to the therapeutic weaponry against HCC.