P. A. Erba

Radiolabeled Somatostatin Analogues Therapy in Advanced Neuroendocrine Tumors: A Single Centre Experience

The aim of this study was to assess the efficacy of PRRT in patients with advanced neuroendocrine tumors (NETs). Patients and Methods. From January 2007 to August 2011, we enrolled 65 patients (m/f 38/27; mean age 65 years, range 33–83) with advanced NETs having enhanced SSTR expression, treated with PRRT. The enhanced expression of SSTR was assessed using 68Ga-DOTATOC/DOTATATE PET/CT. Among all the enrolled patients, 6 of them were excluded from the present analysis since they voluntarily interrupted treatment. Mean activity/cycle of 2.6 GBq (90Y-DOTATOC/DOTATATE) or 6.0 GBq (177Lu-DOTATOC/DOTATATE) was administrated intravenously (max 9 cycles). Results. Complete response (CR) was found in 1/59 (2%) patients, partial remission (PR) in 24/59 (40.5%) patients, stable disease (SD) in 24/59 (40.5%), and progression (PD) in 10/59 (17%) patients. The overall tumor response rate (CR + PR) was 42.5%. In 40.5% of patients, the disease could be stabilized. Overall, 49 out of 59 patients had no tumor progression (83%). Twelve patients out of 59 (20%) had grade 2-3 hematological side effects including anemia, thrombocytopenia, and leukopenia. Long-term nephrotoxicity was observed in 3 patients (2 moderate, 1 severe). Conclusions. PRRT is a promising perspective for patients with advanced NETs.

Diagnostic performances of [18F]fluorocholine positron emission tomography in brain tumors

BACKGROUND Brain tumors characterization by molecular imaging that allows the depiction of brain lesions metabolic pattern is crucial. Our study aimed to: 1) to evaluate the diagnostic performances of [18F]fluoroethylcholine positron emission tomography/computed tomography ([18F]FECH PET/CT), and 2) correlate PET imaging derived parameters of [18F]FECH to survival in brain tumors. METHODS From 2009 to 2012, we enrolled 30 patients who underwent [18F]FECH PET/CT. Final diagnosis was established by clinical and radiological follow-up. RESULTS Final diagnosis was consistent with tumor disease in 27/30 cases. In 3/30 cases tumor disease was ruled out. [18F]FECH PET/CT resulted true positive and negative in 21/30 and 9/30 patients, respectively. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of [18F]FECH PET/CT were 78%, 100%, 100%, 33%, and 80%, respectively. Mean and maximum standardized uptake value (SUVmean and SUVmax) resulted statistically correlated to histology (P=0.0255 and P=0.0222, respectively). Using a SUVmax cut-off of 2.0 or 3.2, we distinguished between low- and high-grade gliomas with a good specificity (70% and 80%, respectively). SUVmax and histology resulted correlated to overall survival and disease related survival at multivariate analysis. CONCLUSIONS Our results, worthy of further investigations, show high diagnostic performances of [18F]FECH PET/CT, and a correlation between PET imaging derived parameters and survival.

Peripheral dual-phase bicompartmental lymphoscintigraphy to localize the site of lymphatic obstruction and guide therapeutic management of patients

Objective To comparatively assess two techniques, radiocolloid SPECT lymphoscintigraphy and interstitial MR lymphography using SPIO, in animal models and tongue cancer patients. Materials and Methods We used twenty one 8-weekold male nude mice of strain BALB/c Slc-nu/nu. The 4.7-tesla MRI equipment was used to detect the SNs. T2*WI of gradient-echo sequences was acquired sequentially up to 24 h after administering SPIO, ferucarbotran. Tc-phytate SPECT lymphoscintigraphy was taken at 30 min. after the injection to detect the SNs using animal-dedicated whole-body SPECT scanner. The injection was submucosally performed in the right tongue margin of each mouse. Reading performances concerning SN visualization and its quality on interstitial MR lymphogram and SPECT lymphoscintigram were performed by 3 radiologists. Three patients with tongue cancer underwent both Tc-phytate lymphoscintigraphy and interstitial MR lymphography using ferucarbotran in the method similar to the animal study. Results The SN intensities were 0.43 for the right, 0.61 for the left at 30 min after ferucarbotran injection, with gradual decrease in intensity. The mean numbers of lymph nodes visualized were 4.00 nodes for on SPECT lymphoscintigram and 2.0 for interstitial MR lymphogram. There was statistically significant difference in the mean scores between SPECT lymphoscintigraphy and interstitial MR lymphography (two-factor mixed design with repeated measures on one factor: p < 0.0002). The human study showed the results similar to the mice study, with higher quality MR images than the mice images. Conclusions In our comparative study using mice, the results of radiocolloid lymphoscintigraphy were superior to those of interstitial MR lymphography, while SPIO has a potential of being employed for sentinel node navigation surgery by interstitial MR lymphography in the head and neck region.