Optimizing the Radiation Treatment Planning of Brain Tumors by Integration of Functional MRI and White Matter Tractography

Background: Diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) present the ability to selectively protect functional regions and fiber tracts of the brain when brain tumors are treated with radiotherapy. Objective: This study aimed to assess whether the incorporation of fMRI and DTI data into the radiation treatment planning process of brain tumors could prevent the neurological parts of the brain from high doses of radiation. Material and Methods: In this investigational theoretical study, the fMRI and DTI data were obtained from eight glioma patients. This patient-specific fMRI and DTI data were attained based on tumor location, the patient’s general conditions, and the importance of the functional and fiber tract areas. The functional regions, fiber tracts, anatomical organs at risk, and the tumor were contoured for radiation treatment planning. Finally, the radiation treatment planning with and without fMRI & DTI information was obtained and compared. Results: The mean dose to the functional areas and the maximum doses were reduced by 25.36% and 18.57% on fMRI & DTI plans compared with the anatomical plans. In addition, 15.59% and 20.84% reductions were achieved in the mean and maximum doses of the fiber tracts, respectively.  Conclusion: This study demonstrated the feasibility of using fMRI and DTI data in radiation treatment planning to maximize radiation protection of the functional cortex and fiber tracts. The mean and maximum doses significantly decreased to neurologically relevant brain regions, resulting in reducing the neuro-cognitive complications and improving the patient’s quality of life

Grading of Gliomas by Contrast-Enhanced CT Radiomics Features

Background: Gliomas, as Central Nervous System (CNS) tumors, are greatly common with 80% of malignancy. Treatment methods for gliomas, such as surgery, radiation therapy, and chemotherapy depend on the grade, size, location, and the patient’s age. Objective: This study aimed to quantify glioma based on the radiomics analysis and classify its grade into High-grade Glioma (HGG) or Low-grade Glioma (LGG) by various machine-learning methods using contrast-enhanced brain Computerized Tomography (CT) scans. Material and Methods: This retrospective study involved acquiring and segmenting data, selecting and extracting features, classifying, analyzing, and evaluating classifiers. The study included a total of 62 patients (31 with LGG and 31 with HGG). The tumors were segmented by an experienced CT-scan technologist with 3D slicer software. A total of 14 shape features, 18 histogram-based features, and 75 texture-based features were computed. The Area Under the Curve (AUC) and Receiver Operating Characteristic Curve (ROC) were used to evaluate and compare classification models. Results: A total of 13 out of 107 features were selected to differentiate between LGGs and HGGs and to perform various classifier algorithms with different cross-validations. The best classifier algorithm was linear-discriminant with 93.5% accuracy, 96.77% sensitivity, 90.3% specificity, and 0.98% AUC in the differentiation of LGGs and HGGs.  Conclusion: The proposed method can identify LGG and HGG with 93.5% accuracy, 96.77% sensitivity, 90.3% specificity, and 0.98% AUC, leading to the best treatment for glioma patients by using CT scans based on radiomics analysis

The Cytotoxicity of Dextran-coated Iron Oxide Nanoparticles on Hela and MCF-7 Cancerous Cell Lines

Background: Recently, iron oxide nanoparticles have attracted attention in various diagnosis and treatment fields. The aim of the present study was to investigate the cytotoxicity of various concentrations and incubation times of dextran-coated iron oxide nanoparticles (DIONPs) on HeLa and MCF-7 cancerous cell lines. Methods: This in-vitro study was conducted at Pharmaceutical Sciences Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran in 2016. The dextran-coated iron oxide nanoparticles (DIONPs) uptake and cytotoxicity at different concentrations (10, 40 and 80 µg/ml) and different incubation times (6, 12 and 24 h) were assessed on HeLa and MCF-7 cell lines. The viability of the cells was measured by MTT assay. Results: DIONPs entered into the HeLa and MCF-7 cells. After 6, 12 and 24 h incubation times and in all concentrations, the viability of HeLa cells was more than 94%. For MCF-7 cell line, increasing incubation time from 6 to 24 h at a concentration of 10 μg/ml decreased the cells viability from 98% to 95%. When the cells were exposed to concentrations of 40 and 80 μg/ml of the nanoparticles, significant reductions in the cells viability was observed from 98% to 91.6% and from 95% to 88%, respectively. Conclusion: DIONPs cytotoxicity increased by increasing the incubation time from 6 to 24 h and also increased with increasing the nanoparticles concentration from 0 to 80 μg/ml. In general, DIONPs did not cause considerable toxicity in both cell lines especially at lower concentrations. Therefore, these nanoparticles are good candidates for use in biomedical and cancer research studies

Investigation of Specific Targeting of Triptorelin-Conjugated Dextran-Coated Magnetite Nanoparticles as a Targeted Probe in GnRH+ Cancer Cells in MRI

In recent years, the conjugation of superparamagnetic iron oxide nanoparticles (SPIONs), as tumor-imaging probes for magnetic resonance imaging (MRI), with tumor targeting peptides possesses promising advantages for specific delivery of MRI agents. The objective of the current study was to design a targeted contrast agent for MRI based on Fe3O4 nanoparticles conjugated triptorelin (SPION@triptorelin), which has a great affinity to the GnRH receptors. The SPIONs-coated carboxymethyl dextran (SPION@CMD) conjugated triptorelin (SPION@CMD@triptorelin) were synthesized using coprecipitation method and characterized by DLS, TEM, XRD, FTIR, Zeta, and VSM techniques. The relaxivities of synthetized formulations were then calculated using a 1.5 Tesla clinical magnetic field. MRI, quantitative cellular uptake, and cytotoxicity level of them were estimated. The characterization results confirmed that the formation of SPION@CMD@triptorelin has been conjugated with a suitable size. Our results demonstrated the lack of cellular cytotoxicity of SPION@CMD@triptorelin, and it could increase the cellular uptake of SPIONs to MDA-MB-231 cancer cells 6.50-fold greater than to SPION@CMD at the concentration of 75 μM. The relaxivity calculations for SPION@CMD@triptorelin showed a suitable r2 and r2/r1 with values of 31.75 mM−1·s−1 and 10.26, respectively. Our findings confirm that triptorelin-targeted SPIONs could provide a T2-weighted probe contrast agent that has the great potential for the diagnosis of GnRH-positive cancer in MRI