Usefulness of 18f-FDG PET-CT in Staging, Restaging, and Response Assessment in Pediatric Rhabdomyosarcoma

Rhabdomyosarcoma is the most common soft-tissue sarcoma of childhood. Despite clinical advances, subsets of these patients continue to suffer high morbidity and mortality rates associated with their disease. Following the European guidelines for 18F-FDG PET and PET-CT imaging in pediatric oncology, the routine use of 18F-FDG PET-CT may be useful for patients affected by rhabdomyosarcoma, in staging, in the evaluation of response to therapy, and for restaging/detection of relapse. The European Pediatric Protocols are very old, and for staging and restaging, they recommend only radionuclide bone scan. The 18F-FDG PET-CT exam is listed as an optional investigation prescribed according to local availability and local protocols in the investigations panel required at the end of the treatment. We present two cases highlighting the usefulness of 18F-FDG PET-CT in managing pediatric patients affected by rhabdomyosarcoma, providing some bibliographic references

Unusual diagnostic findings in temporal lobe epilepsy: A combined MRI and 18F-dopa case study

Temporal lobe epilepsy is the most common focal epilepsy in adults and often causes pharmacoresistant seizures. Magnetic resonance imaging (MRI) and PET studies have widely demonstrated a number of morphological and molecular abnormalities in epilepsy. However, considering the dopaminergic system, only a bilateral 18F-DOPA uptake reduction within the basal ganglia has been described. We report the unusual finding of increased 18F- DOPA uptake in a patient with focal recurrent seizures and "deja vu" experiences in the setting of cortical swelling detected at MRI exam. The final diagnosis was in in keeping with hippocampal sclerosis, confirmed during follow-up MR exams. In this case 18F-DOPA uptake may represent increased dopamine transport induced by seizures. Nuclear medicine physicians and radiologists should be aware of clinical and electroencephalo- graphic findings when interpreting brain areas of tracer uptake, which are not always related to malignancy

Non invasive determination of IDH mutation status in high-grade gliomas: utility of ADC maps and (18F)-DOPA PET/ TC

Aim The brain tumors new classification (2016 WHO) distinguishes diffuse gliomas based on the molecular characteristics of isocitrate dehydrogenase (IDH) in IDH-mutated, IDH-wild type (WT) and not otherwise specified. The evaluation of IDH mutation status has diagnostic, prognostic and therapeutic implications. The aim of this study is to evaluate whether the analysis of ADC maps and (18F-DOPA) can non-invasively predict the IDH mutation status. Conventional MRI and ADC maps of 16 patients (11-M, 5-F) with histological diagnosis of high-grade diffuse glioma GIII, GIV and the evaluation of IDH mutation status (9-MUT, 7-WT), were retrospectively evaluated. Methods All MRI were performed on a 1.5T MR scan (GE-optima 450). In order to place the ROIs on the solid components of the lesion, the ADC maps were elaborated and co-registered with the T2w and c.e.T1w images. The ADC-mean values were calculated, choosing the lowest values for each patient. The same procedure was performed with PET/CT scan using (18F)-DOPA as tracer. We placed (VOIs) in the same area where was applied the ROIs in RM scan in both groups of patients in order to calculate the SUV-mean values between IDH-MUT and IDH-WT. To compare the ADCmean and SUVmean values between IDH-MUT and IDH-WT performing Student's "t" test, considering significant value of p <0.05 in both groups. Results The ADCmean values in IDH-WT patients (0.86x10-3mm2/s \ub1 0.06)were lower than those of IDH-MUT patients (1.24x10-3mm2 /s \ub10.19) with difference between the two groups significant for p<0.01. The value of ADC 65 1.01 x10-3mm2/s can be considered asa "cut-off" to differentiate them mutation status. The ratio between tumor uptake to background in PET/CT scan in IDH-WT group was (2.59x10-3mm2/s \ub1 0,448), higher than in IDH-MUT group (1.9x10-3mm2/s \ub1 0,533), with a significative p<0,05. Conclusion In the standard routine MR and PET are already assested to evaluate brain tumors but they are both of limited value if advanced techniques are not applied and if there is no integration of anatomical and functional data. In our experience adding quantitative data such as ADC to conventional MR and semi-quantitative analysis to PET with aminoacid tracers like DOPA is necessary for a better comprehension of tumor nature. In the era of molecular imaging this is a novel approach that could be introduced as a non-invasive marker of specific genomic patterns

UNUSUAL LYMPHATIC DRAINAGE TO CONTRALATERAL ROTTER'S LYMPH NODES IN BREAST CANCER: A SPECT/TC LYMPHOSCINTIGRAPHY CASE STUDY

Lymphatic drainage of the breast occurs mainly in ipsilateral axillary nodes, but up to 20\u201330% of cases may present drainage to other locations, although it is usually coupled to ipsilateral axillary nodes. Contralateral axillary drainage in daily clinical practice is very rare (0-2%), even more without associated ipsilateral drainage. We present the case of a 71-year-old woman with a personal history of ductal/lobular carcinoma at 49 years on the left breast and a second primary invasive lobular carcinoma in the right breast. Preoperative lymphoscintigraphy showed absence of lymphatic drainage in the ipsilateral axilla but unusual lymphatic drainage was detected in the contralateral Rotter's lymph nodes as confirmed by SPECT/TC imaging

Predict Treatment Response by Magnetic Resonance Diffusion Weighted Imaging: A Preliminary Study on 46 Meningiomas Treated with Proton-Therapy

none7noObjective: a considerable subgroup of meningiomas (MN) exhibit indolent and insidious growth. Strategies to detect earlier treatment responses based on tumour biology rather than on size can be useful. We aimed to characterize therapy-induced changes in the apparent diffusion coefficient (ADC) of MN treated with proton-therapy (PT), determining whether the pre- and early post-treatment ADC values may predict tumour response. Methods: Forty-four subjects with MN treated with PT were retrospectively enrolled. All patients underwent conventional magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) at baseline and each 3 months for a follow-up period up to 36 months after the beginning of PT. Mean relative ADC (rADCm) values of 46 MN were measured at each exam. The volume variation percentage (VV) for each MN was calculated. The Wilcoxon test was used to assess the differences in rADCm values between pre-treatment and post-treatment exams. Patients were grouped in terms of VV (threshold −20%). A p < 0.05 was considered statistically significant for all the tests. Results: A significant progressive increase of rADCm values was detected at each time point when compared to baseline rADCm (p < 0.05). Subjects that showed higher pre-treatment rADCm values had no significant volume changes or showed volume increase, while subjects that showed a VV < −20% had significantly lower pre-treatment rADCm values. Higher and earlier rADCm increases (3 months) are related to greater volume reduction. Conclusion: In MN treated with PT, pre-treatment rADCm values and longitudinal rADCm changes may predict treatment response.openFeraco, Paola; Scartoni, Daniele; Porretti, Giulia; Pertile, Riccardo; Donner, Davide; Picori, Lorena; Amelio, DanteFeraco, Paola; Scartoni, Daniele; Porretti, Giulia; Pertile, Riccardo; Donner, Davide; Picori, Lorena; Amelio, Dant

Heterogeneous response of cardiac sympathetic function to cardiac resynchronization therapy in heart failure documented by 11[C]-hydroxy-ephedrine and PET/CT

Introduction: Cardiac resynchronization therapy (CRT) is an accepted treatment in patients with end-stage heart failure. PET permits the absolute quantification of global and regional homogeneity in cardiac sympathetic innervation. We evaluated the variation of cardiac adrenergic activity in patients with idiopathic heart failure (IHF) disease (NYHA III-IV) after CRT using 11C-hydroxyephedrine (HED) PET/CT. Methods: Ten IHF patients (mean age. = 68; range. = 55-81; average left ventricular ejection fraction 26 ± 4%) implanted with a resynchronization device underwent three HED PET/CT studies: PET 1 one week after inactive device implantation; PET 2, one week after PET 1 under stimulated rhythm; PET 3, at 3 months under active CRT. A dedicated software (PMOD 3.4 version) was used to estimate global and regional cardiac uptake of HED through 17 segment polar maps. Results: At baseline, HED uptake was heterogeneously distributed throughout the left ventricle with a variation coefficient of 18 ± 5%. This variable markedly decreased after three months CRT (12 ± 5%, p. <. 0.01). Interestingly, subdividing the 170 myocardial segments (17 segments of each patient multiplied by the number of patients) into two groups, according to the median value of tracer uptake expressed as % of maximal myocardial uptake (76%), we observed a different behaviour depending on baseline innervation: HED uptake significantly increased only in segments with "impaired innervation" (SUV 2.61 ± 0.92 at PET1 and 3.05 ± 1.67 at three months, p. <. 0.01). Conclusion: As shown by HED PET/CT uptake and distribution, improvement in homogeneity of myocardial neuronal function reflected a selective improvement of tracer uptake in regions with more severe neuronal damage. Advances in Knowledge: These finding supported the presence of a myocardial regional variability in response of cardiac sympathetic system to CRT and a systemic response involving remote tissues with rich adrenergic innervation. Implication for patient care: This work might contribute to identify imaging parameters that could predict the response to CRT therapy

Mapping brain morphological and functional conversion patterns in predementia late-onset bvFTD

none15Morbelli, Silvia; Ferrara, Michela; Fiz, Francesco; Dessi, Barbara; Arnaldi, Dario; Picco, Agnese; Bossert, Irene; Buschiazzo, Ambra; Accardo, Jennifer; Picori, Lorena; Girtler, Nicola; Mandich, Paola; Pagani, Marco; Sambuceti, Gianmario; Nobili, FlavioMorbelli, Silvia; Ferrara, Michela; Fiz, Francesco; Dessi, Barbara; Arnaldi, Dario; Picco, Agnese; Bossert, Irene; Buschiazzo, Ambra; Accardo, Jennifer; Picori, Lorena; Girtler, NICOLA GIOVANNI; Mandich, Paola; Pagani, Marco; Sambuceti, Gianmario; Nobili, FLAVIO MARIAN