Cristina Messa

Predictive value of pre-therapy (18)F-FDG PET/CT for the outcome of (18)F-FDG PET-guided radiotherapy in patients with head and neck cancer.

PurposeThe aim of this study was to evaluate the predictive role of pre-therapy fluorodeoxyglucose (FDG) uptake parameters of primary tumour in head and neck cancer (HNC) patients undergoing intensity-modulated radiotherapy (IMRT) with simultaneous integrated boost (SIB) on FDG-positive volume—positron emission tomography (PET) gross tumour volume (PET-GTV).MethodsThis retrospective study included 19 patients (15 men and 4 women, mean age 59.2xa0years, range 23–81xa0years) diagnosed with HNC between 2005 and 2011. Of 19 patients, 15 (79xa0%) had stage III–IV. All patients underwent FDG PET/CT before treatment. Metabolic indexes of primary tumour, including metabolic tumour volume (MTV), maximum and mean standardized uptake value (SUVmax, SUVmean) and total lesion glycolysis (TLG) were considered. Partial volume effect correction (PVC) was performed for SUVmean and TLG estimation. Correlations between PET/CT parameters and 2-year disease-free survival (DFS), local recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS) were assessed. Median patient follow-up was 19.2xa0months (range 4–24xa0months).ResultsMTV, TLG and PVC-TLG predicting patients’ outcome with respect to all the considered local and distant disease control endpoints (LRFS, DMFS and DFS) were 32.4xa0cc, 469.8xa0g and 547.3xa0g, respectively. SUVmean and PVC-SUVmean cut-off values predictive of LRFS and DFS were 10.8 and 13.3, respectively. PVC was able to compensate errors up to 25xa0% in the primary HNC tumour uptake. Moreover, PVC enhanced the statistical significance of the results.ConclusionFDG PET/CT uptake parameters are predictors of patients’ outcome and can potentially identify patients with higher risk of treatment failure that could benefit from more aggressive approaches. Application of PVC is recommended for accurate measurement of PET parameters.

Metabolic changes after MRgFUS treatment of a bone metastasis using PET/CT: A case report

Aim of the present study is to evaluate the efficacy of the Magnetic Resonance guided Focused Ultrasound (Insightec ExAblate 2000 system) in a clinical case of a pelvic bone metastasis, accessible to the ultrasonic beam. Multiple 18F-FDG PET/CT examinations allowed to follow the metabolic and morphological modification of the cancerous lesion.

Increased [11C]Choline Uptake in Bronchioloalveolar Cell Carcinoma with Negative [18F]FDG Uptake. A PET/CT and Pathology Study

A case of a patient with bronchioloalveolar cell predominate lung adenocarcinoma (BAC) studied using integrated Positron Emission Tomography and Computed Tomography (PET/CT) with both 18F-fluorodeoxyglucose ([18F]FDG-PET) and [11C]Choline ([11C]Choline-PET) is described, with the aim of evaluating a new non invasive imaging method to detect and stage BAC, and providing information on tumour biology in vivo. The information derived from combining the two tracers could help in distinguishing lung adenocarcinoma with large BAC components ([18F]FDG negative and [11C]Choline positive) from inflammatory lesion ([18F]FDG and [11C]Choline positive). In addition, the simultaneous use of two PET tracers, evaluating two different metabolic pathways, together with histopathologic, immunohistochemical and gene expression analysis, could help to improve understanding of tumour in vivo behaviour.