Radioimmunotherapy in non-Hodgkin lymphoma: Prediction and assessment of response

International audienceNon-Hodgkin lymphoma (NHL) is one of the most common malignancies and a major cause of morbidityand mortality. Radioimmunotherapy (RIT) is a novel modality for treating NHL which offers the combineduse of monoclonal antibodies for specific targeting of malignant cells and radiation for killing these cells.Despite the promising results favoring RIT in several clinical studies in different target populations andNHL types, Food and Drug Administration (FDA) approval for RIT agents is restricted to a limited numberof indications and agents, maybe because of several ambiguities that still exist in the field. One of theseambiguities are the lack of evidence-based prognostic factors that determine what patient populationwould benefit most from RIT, which is essential to know in order to optimize the efficacy and safetyof treatment with RIT. As well as selecting the best patient population for RIT, it is important to assessthe response to RIT in order to provide further treatment strategies or avoid unnecessary therapies anddiagnostic procedures. In this review we have explored the details of how to predict the efficiency of RIT

18F-FDOPA PET Compared With 123I-Metaiodobenzylguanidine Scintigraphy and 18F-FDG PET in Secreting Sporadic Pheochromocytoma

International audienceWe report the case of a 23-year-old man presenting a right hypersecreting pheochromocytoma, falsely negative on 18 F-FDG PET/CT and on 123 I-metaiodobenzylguanidine (123 I-MIBG) scintigraphy but strongly positive on 18 F-FDOPA PET/CT. Functional imaging has a key role in diagnosis and prognosis of pheochromocytomas, but choosing the most relevant modality remains difficult. Despite its high specificity, 123 I-MIBG has a limited sensitivity. 18 F-FDG can be used, but it is an unspecific tracer, and 18 F-FDG uptake in brown adipose tissue can hinder the analysis. However, 18 F-FDOPA shows very high sensitivity and specificity in pheochromocyto-mas with fewer drug interferences than 123 I-MIBG

Which radionuclide, carrier molecule and clinical indication for alpha-immunotherapy?

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Isolation of Coxiella burnetii from an acromioclavicular infection with low serological titres

International audienceCoxiella burnetii acromioclavicular infection is a new infectious focus, evidenced here for the first time using the gold standard, culture. Positron emission tomography had a crucial role in identifying the deep infectious focus, even when C. burnetii serological titres were low

Prognostic value of FDG-PET indices for the assessment of histological response to neoadjuvant chemotherapy and outcome in pediatric patients with Ewing sarcoma and osteosarcoma.

The objective of this retrospective work was to evaluate the prognostic value on histological response and survival of quantitative indices derived from FDG-PET performed before and after chemotherapy (CHT), in a homogeneous pediatric Ewing sarcoma (EWS) and Osteosarcoma (OST) population.Thirty-one patients with EWS and 31 with OST were included. All patients were treated with neoadjuvant CHT, and underwent surgery for local control. All patients had FDG-PET at diagnosis and after CHT, prior to surgery. Several parameters were evaluated: SUVmax, SUVpeak, SUVmean, metabolic tumor volume, total lesion glycolysis, 7 textural features and 3 shape features (SF). The segmentation was performed using an adaptive approach. Results were compared to histopathological regression of the resected tumor and to clinical follow-up for survival evaluation.For EWS, univariate analysis did not highlight any prognostic value on histological response, or survival regardless of all the considered metrics. For OST, only one of the SF, namely elongation, was significantly associated with PFS and OS on both univariate and multivariate analysis (PFS: p = 0.019, HR = 5.583; OS: p = 0.0062, HR = 7.113).Only elongation determined on initial FDG-PET has a potential interest as a prognostic factor of PFS and OS in pediatric OST patients. Unlike recent studies of the literature realized in adult population, all the metrics reveal limited additional prognostic value in pediatric EWS patients. This seems to reinforce the question of whether children experience different subtypes of the same pathologies than older patients, with different outcomes

Leveraging RSF and PET images for prognosis of Multiple Myeloma at diagnosis

International audiencePurpose Multiple myeloma (MM) is a bone marrow cancer that accounts for 10% of all hemato-logical malignancies. It has been reported that FDG PET imaging provides prognostic information for both baseline and therapeutic follow-up of MM patients using visual analysis. In this study, we aim to develop a computer-assisted method based on PET quantitative image features to assist diagnoses and treatment decisions for MM patients.Methods Our proposed model relies on a two-stage method with Random Survival Forest (RFS) and Variable importance (VIMP) for both feature selection and prediction. The targeted variable for prediction is the progression-free survival (PFS). We consider texture-based (radiomics), conventional (e.g. SUVmax) and clinical biomarkers. We evaluate PFS predictions in terms of C-index and final prognosis separation in two risk groups, from a database of 66 patients who were part of the prospective multi-centric french IMAJEM study.Results Our method (VIMP+RSF) provides better results (1-C-index of 0.36) than conventional methods such as Lasso-Cox and Gradient-Boosting Cox (0.48 and 0.56 respectively). We experimentally proved the interest of using selection (0.61 for RSF without selection) and showed that VIMP selection is more stable and gives better results than Minimal-depth and Variable-Hunting (0.47 and 0.43). The approach gives better prognosis group separation (a p-value of 0.05 against 0.11 to 0.4 for others).Conclusion Our results confirm the predictive value of radiomics for MM patients, in particular, they demonstrate that quantitative/heterogeneity image-based features reduce the error of the predicted progression. To our knowledge, this is the first work using RFS on PET images for the progression prediction of MM patients. Moreover, we provide an analysis of the feature selection process, which points towards the identification of clinically relevant biomarkers

Mild sporadic primary hyperparathyroidism: high rate of multiglandular disease is associated with lower surgical cure rate

International audienceBACKGROUND:Mild primary hyperparathyroidism (serum calcium ≤ 2.85 mmol/L) is the most representative form of pHPT nowadays. The aim of this study was to evaluate its subtypes and the multiglandular disease (MGD) rate as it may lower the sensitivity of preoperative parathyroid scintigraphy and the surgical cure rate.METHODS:We retrospectively included patients with mild pHPT who underwent parathyroid dual-tracer scintigraphy with 99mTc-MIBI SPECT/CT and surgery between January 2013 and December 2015. Cure was defined as normalization of serum calcium (or PTH in the normocalcemic form) at 6 months. MGD was defined by either two abnormal resected glands or persistent disease after resection of at least one abnormal gland.RESULTS:We included 121 patients. Median preoperative serum calcium was 2.68 mmol/L and median PTH was 83.4 pg/mL. A total of 141 glands were resected (95 adenomas, 33 hyperplasias). The subtypes were 57% classic, 32.2% normohormonal, and 10.7% normocalcemic. MGD occurred in 23.5% of patients divided as 13%, 30%, and 64% respectively (p = 0.0011). The surgical cure rate was 85.2%. The normocalcemic form had lower cure rate than the normohormonal (45% vs 84%, p = 0.018) and classic forms (45% vs 93%, p = 0.0006). MIBI scintigraphy identified at least one abnormal lesion, later confirmed by the pathologist in 90/98 patients, making the sensitivity per patient 91.8% (95% CI 84.1-96.2%).CONCLUSIONS:MGD is strongly associated with mild pHPT, especially the normocalcemic form where it accounts for 64% of cases. Bilateral neck exploration should be performed in this population to improve the cure rate, even if the scintigraphy shows a single focus