Objectives The study is to evaluate biodistribution, dosimetry, safety, and clinical usefulness of 18F-AlF-NOTA-octreotide (18F-OC) PET/CT in combination with 18F-FDG PET/CT for detection of neuroendocrine neoplasms (NENs). Methods The biodistribution, dosimetry, and safety of 18F-OC were evaluated in 3 healthy volunteers. Twenty-two NEN patients underwent PET/CT at 60 minutes after intravenous injection of 3.7 to 4.44 MBq (0.1–0.12 mCi) per kilogram of body weight of 18F-OC. This was followed by 18F-FDG PET/CT within a 2-week period. Results 18F-OC was well tolerated by all healthy volunteers and NEN patients. The calculated effective dose of 18F-OC was 0.023 ± 0.002 mSv/MBq. In NEN patients, we observed prominent 18F-OC tumor uptake and high tumor-to-background ratios. Tumor uptake of 18F-OC was greater than that of 18F-FDG, and this was particularly evident in G2 NENs (median SUVmax, 45.6 vs 4.3; P < 0.015). Tumor uptake of 18F-OC or 18F-FDG was significantly correlated with tumor differentiation (P < 0.05). Dual tracer PET/CT detected more lesions and also yielded information on the biological status of tumors. Conclusions The tracer 18F-OC exhibited favorable safety and dosimetry profiles. 18F-OC provided superior imaging of well-differentiated NENs and significantly higher tumor-to-background ratio compared with 18F-FDG. Combining 18F-FDG with 18F-OC PET/CT has the potential to improve NEN staging and management of patient treatment.

The development of efficient strategies for the magnetic hyperthermia ablation of tumors remains challenging. To overcome the significant safety limitations, we developed a thermally contractible, injectable and biodegradable material for the minimally invasive and highly efficient magnetic hyperthermia ablation of tumors. This material was composed of hydroxypropyl methyl cellulose (HPMC), polyvinyl alcohol (PVA) and FeO. The thermal contractibility of HPMC/FeO was designed to avoid damaging the surrounding normal tissue upon heating, which was confirmed by visual inspection, ultrasound imaging and computed tomography (CT). The efficient injectability of HPMC/FeO was proven using a very small needle. The biosafety of HPMC/FeO was evaluated by MTT and biochemical assays as well as flow cytometry (FCM). All the aforementioned data demonstrated the safety of HPMC/FeO. The results of in vitro and ex vivo experiments showed that the temperature and necrotic volume of excised bovine liver were positively correlated with the HPMC/FeO weight, iron content and heating duration. The in vivo experimental results showed that the tumors could be completely ablated using 0.06 ml of HPMC/60%FeO after 180 s of induction heating. We believe that this novel, safe and biodegradable material will promote the rapid bench-to-bed translation of magnetic hyperthermia technology, and it is also expected to bring a new concept for the biomaterial research field.

BackgroundBrainstem dose limitations influence radiation dose reaching to tumor in the patients with locally-advanced nasopharyngeal cancer (NPC).MethodsA retrospective analysis of the prognostic value of the distance between the primary tumor and brainstem (Dbs) in 358 patients with locally-advanced NPC after intensity-modulated radiation therapy (IMRT). Receiver operating characteristic (ROC) curves were used to identify the cut-off value to analyze the impact of Dbs on tumor dose coverage and prognosis.ResultsThe three-year overall survival (OS), local relapse-free survival (LRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) were 88.8 vs. 78.4 % (P = 0.007), 96.5 vs. 91.1 % (P = 0.018), 87.8 vs. 79.3 % (P = 0.067), and 84.1 vs. 69.6 % (P = 0.002) for the patients with the Dbs > 4.7 vs. ≤ 4.7 mm, respectively. ROC curves revealed Dbs (4.7 mm) combined with American Joint Committee on Cancer (AJCC) T classification had a significantly better prognostic value for OS (P < 0.05).ConclusionsDbs (≤4.7 mm) is an independent negative prognostic factor for OS/LRFS/DFS and enhances the prognostic value of T classification in the patients with locally-advanced NPC.

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The aim of this study was to clarify the prognostic role of paranasal sinus invasion in advanced NPC patients. Data of patients (n = 295) with advanced NPC (T3/T4N0‐3 M0) treated with intensity‐modulated radiation therapy were retrospectively analyzed. Staging was according to the AJCC/UICC eighth edition staging system. Overall survival (OS), local recurrence‐free survival (LRFS), distant metastasis‐free survival (DMFS), and disease‐free survival (DFS) were calculated, and differences were compared between patients with and without paranasal sinus invasion. Multivariate analysis was used to identify the independent predictors of different survival parameters. Paranasal sinus invasion was present in 126 of 295 (42.7%) patients. Sphenoid, ethmoid, maxillary, and frontal sinus involvements were present in 123 of 295 (41.7%), 95 of 295 (32.2%), 45 of 295 (15.3%), and 0 of 295 (0%), respectively. All survival parameters were significantly better in patients without paranasal sinus invasion. When paranasal sinus invasion was reclassified as T4 instead of T3, all survival rates, other than LRFS (P = 0.156), were significantly better in the new T3 patients, and differences in all survival parameters remained nonsignificant between T3 with paranasal sinus invasion and T4 without paranasal sinus invasion patients (all P > 0.05). In multivariate analysis, paranasal sinus invasion was found to be an independent negative prognostic factor for OS, DFS, and DMFS (P = 0.016, P = 0.004, and P = 0.006, respectively), but not for LRFS (P = 0.068). Paranasal sinus invasion has prognostic value in advanced NPC. It may be reasonable to classify paranasal sinus invasion as T4 stage.