Prognostic value of functional tumor burden on 68Ga-DOTATOC PET/CT in patients with pancreatic neuro-endocrine tumors.

Despite their relative quiescence, pancreatic neuro-endocrine tumors (pNET) can correspond to various presentations and outcomes. Several prognostic factors have been identified, including maximal standardized uptake value of the most intense focus (maxSUVmax) on Positron Emission Tomography (PET) with a somatostatin analogue. Herein, we investigate the prognostic value on progression free-survival of the total functional tumor volume (TFTV) measured by 68Ga-DOTATOC PET. From patients who underwent 68Ga-DOTATOC PET from 2008 to 2014, we selected consecutive patients with G1 or G2 pNET (2010 World Health Organization classification), at least one abnormal focus on PET and available follow-up data. TFTV was computed by summing the volumes of all pathological foci, delineated use of 41% of its SUVmax for each threshold focus. Fifty patients were included. During the follow-up period, 33 patients had stable or responsive disease (66%; median duration 28.5 months; range 6.3-77.7 months) and 17 patients experienced disease progression (34%; median progression time 21 months; range 6.7-44.7 months). Median PFS was 43.5 months. The best TFTV cut-off for predicting progression within 24 months was 13.8 cm3. Multivariate analysis determined that TFTV greater than 13.8 cm3 was the only criterion considered a significant risk factor for tumor progression (HR 2.9; p=0.0003). A significant difference in PFS was observed for TFTV (<13.8 vs. ≥ 13.8 cm3: median not reached vs. 25 months; p=0.0001). Our study suggests that 68Ga-DOTATOC TFTV measured on PET images is a valuable prognostic biomarker in patients with well-differentiated pNETs of all stages.

[PET/CT and biochemical recurrence of prostate adenocarcinoma: Added value of 68Ga-PSMA-11 when 18F-fluorocholine is non-contributive]. / TEP/TDM et récidive biologique d'adénocarcinome prostatique : apport du 68Ga-PSMA-11 lorsque la 18F-fluorocholine n'est pas contributive.

INTRODUCTION: Since April 201, we have introduced PET/CT using a ligand of prostate-specific membrane antigen labeled with gallium-68 (PSMA-11). We aimed to evaluate its positivity rate and impact in patients presenting biochemical recurrence of prostate cancer whose 18F-fluorocholine (FCH) PET/CT was non-contributive. PATIENTS AND METHOD: Patients were prospectively included between April and December 2016. PET/CT was performed 60min after injection of 2MBq/kg of body mass of 68Ga-PSMA-11. Three anatomical areas were considered: prostatic lodge, pelvic lymph nodes and distant locations. The impact of PSMA-11 PET/CT was assessed by comparing changes in therapeutic strategy decided during multidisciplinary meeting. RESULTS: Thirty-three patients were included. The mean PSA serum level measured on the month of the PSMA-11 PET/CT was 2,8ng/mL. Twenty-five (76%) PSMA-11 PET/CT were positive, 7 (21%) negative and 1 (3%) equivocal. Of 11 patients whose FCH PET/CT showed equivocal foci, PSMA-11 PET/CT confirmed those foci in 5 cases. Follow-up was available for 18 patients (55%). PSMA-11 PET/CT results led to a change in management in 12 patients (67%). CONCLUSION: 68Ga-PSMA-11 PET/CT is useful in detecting recurrence of prostate cancer, by identifying residual disease which was not detected on other imaging modalities and by changing management of 2 patients out of 3. LEVEL OF EVIDENCE: 5.

[Multimodal imaging of ischemic heart diseases: A 2015 update]. / Imagerie multimodale des cardiopathies ischémiques : possibilités et indications en 2015.

Current realities and future possibilities of imaging in the ischemic heart diseases are very broad and constantly evolving, with the improvement of existing technologies and the introduction of new features such as dual-energy CT, strain ultrasound, multimodality fusion or perfusion MRI. Regular collaboration between prescribing clinicians, cardiologists, radiologists and nuclear radiologists is therefore essential to tailor the examination to the specific clinical question. The indications for each modality will therefore depend on its diagnostic performance, cost, acquisition and post-processing times and eventual radiation exposure. This review will detail principles and applications of current cardiac imaging examinations: echocardiography, nuclear medicine, MRI, CT and coronary angiography, emphasizing their current strengths and weaknesses in the ischemic heart diseases management.