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Objective: DNA copy number alterations and difference expression are frequently observed in ovarian cancer. The purpose of this way was to pinpoint gene expression change that was associated with alterations in DNA copy number and could therefore enlighten some potential oncogenes and stability genes with functional roles in cancers, and investigated the bioinformatics significance for those correlated genes. Method: We obtained the DNA copy number and mRNA expression data from the Cancer Genomic Atlas and identified the most statistically significant copy number alteration regions using the GISTIC. Then identified the significance genes between the tumor samples within the copy number alteration regions and analyzed the correlation using a binary matrix. The selected genes were subjected to bioinformatics analysis using GSEA tool. Results: GISTIC analysis results showed there were 45 significance copy number amplification regions in the ovarian cancer, SAM and Fisher’s exact test found there have 40 genes can affect the expression level, which located in the amplification regions. That means we obtained 40 genes which have a correlation between copy number amplification and drastic up- and down-expression, which p-value ere overlapped with the several published studies which were focused on the gene study of tumorigenesis. Conclusion: The use of statistics and bioinformatics to analyze the microarray data can found an interaction network involved. The combination of the copy number data and expression has provided a short list of candidate genes that are consistent with tumor driving roles. These would offer new ideas for early diagnosis and treat target of ovarian cancer.

Purpose: This study aims to evaluate the treatment plans of Volumetric-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT) techniques for cervical-thoracic esophageal cancers. Methods and Materials: Sixty patients were retrospectively identified. Several parameters were evaluated based on target conformity and dose-volume histograms of organs at risk (lung, spinal cord, and heart). A phantom for time comparison was also assessed for each plan. Results: The IMRT plans (5f-IMRT: V95% = 99.4 ± 0.3, 7f-IMRT: V95% = 99.8 ± 0.1) results in better PTV coverage than RA plans (Single-arc: V95% = 95.8 ± 3.2, Double-arc: V95% = 95.4 ± 2.3). The target dose conformity of the 5f-IMRT plan was inferior to all plans (CI = 70.4 ± 7.1). The Single-arc plan achieved the best conformity (CI = 72.5 ± 4.6), whereas the Double-arc plan (CI = 72.1 ± 5.1) was slightly inferior to the Single-arc plan but superior to the 7f-IMRT plan (CI = 71.7 ± 8.6). The total MU was reduced by 42.1% in VMAT plan. The average MU needed to deliver the dose of 60 Gy for Single-arc (423.5 ± 52.1 MU) was found to be the least. Similarly, the average MU for the 5f-IMRT, 7f-IMRT and Double-arc were 868.2 ± 182.0 MU, 870.0 ± 225.3 MU and 548.8 ± 47.2 MU, respectively. The delivery time in VMAT plans was reduced from 193.8 seconds to 99.2 seconds by around 48.8% compared to IMRT plans. Conclusion: For similar PTV parameters, VMAT delivers a lower dose to organs at risk than IMRT in a shorter time, and this has warranted clinical implementation.

Purpose: Verified the delivered dose distribution of lung cancer Stereotactic Body Radiotherapy (SBRT) using the cone-beam CT images. Methods: Twenty lung cancer patients who underwent SBRT with 100 CBCT images were enrolled in this study. Delivered dose distributions were recalculated on CBCT images with the deformed and non-deformed methods, respectively. The planned and delivered dose distributions were compared using the dose-volume histograms. Results: The delivered target coverage (V100) per patient inside target volume deviated on average were 0.83% ± 0.86% and 1.38% ± 1.40% for Pct vs. Pcbct and Pct vs. Pdcbct, respectively. The Conformity Index (CI) and Gradient Index (GI) showed a good agreement among the plans. For the critical organs, only minor differences were observed between the planned dose and the delivered dose. Conclusions: CBCT images were a useful tool for setup and dose delivery verification for lung cancer patients who underwent SBRT.