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Background: The purpose is to investigate the efficacy of distant metastasis (DM) and locoregional recurrences (LRs) prediction through radiomics and dosimics in head-and-neck cancer (HNC) cases. Methods: The cases of HNC were obtained from The Cancer Imaging Archive. For the radiomics model, the features were extracted from the pretreatment computed tomography image by the pyradiomics, then the condensed features were selected as the clinically related features by the Boruta method. Finally, the random forest was used to construct the DM and LR prediction model by inputting those condensed features. For the dosiomics model, the features were extracted from the 3-dimensional dose distribution from radiation treatment plans. The radiomics and dosiomics condensed features were utilized to training and validate the prediction model's performance. The area under the curve (AUC) value and receiver operating characteristic (ROC) curve were used to assess and compare these models. Results: Seven related features were extracted by the Boruta algorithm, which included one radiomics and two dosiomics features for the DM; two radiomics and two dosiomics features for the LR. Independent training and validation of the prediction and prognostic performance of the model have been observed. The roc-AUC values of the training model for the Rmodel and Dmodel were 0.793 and 0.797, 0.657 and 0.650 for the DM and LR; the roc-AUC values of the validation model for the Rmodel and Dmodel were 0.733 and 0.767, 0.646 and 0.6 for the DM and LR. The roc-AUC values of the training and validation for the radiomics and dosiomics integration model were 0.772 and 0.7, 0.792 and 0.762 for the DM and LR, respectively. Conclusion: Integration of radiomics and dosiomics prediction model can benefit LR in the radiotherapy patient of the head-and-neck squamous cell carcinoma, so the dosiomics should not be neglected for the related investigations.

Abstract Objective The purpose of this study is to investigate the dosimetric advantages of volumetric modulated arc therapy (VMAT) in the treatment of intraocular cancer by comparing it directly with three-dimensional conformal radiotherapy (CRT) and intensity-modulated radiotherapy (IMRT). Methods CRT plan, 7f-IMRT plan, and one-arc VMAT plan were generated for 14 intraocular cancer patients. Dosimetric and biological quality indices for target volume and organs at risks (OARs) were evaluated and compared. Results The target coverage presented by V95 for CRT, IMRT and VMAT were 95.02% ± 0.67%, 95.51% ± 2.25%, and 95.92% ± 3.05%, respectively. The homogeneity index (HI) for CRT, IMRT and VMAT were 0.15 ± 0.05, 0.23 ± 0.05, and 0.23 ± 0.06, respectively. IMRT and VMAT greatly decreased the dose to ipsilateral lens compared with CRT with a D1 of 2972.66 ± 1407.12 cGy, 3317.82 ± 915.28 cGy and 4809.54 ± 524.60 cGy for IMRT, VMAT and CRT, respectively. Similar results were observed for ipsilateral eyeballs. IMRT and VMAT also spared better on brainstem, optical nerves and optical chiasm compared CRT. However, CRT achieved lower dose to the eyeballs compared with IMRT and VMAT. VMAT and IMRT showed mixed results on target coverage and OAR sparing. The average MUs and delivery time of IMRT and VMAT were 531.25 ± 81.21 vs. 400.99 ± 61.49 and 5.05 ± 0.53 vs.1.71 ± 0.69 min, respectively. Conclusions Although no clear distinction on PTV coverage among CRT, IMRT and VMAT plans was observed in the treatment of intraocular cancer, VMAT and IMRT achieved better homogeneity and conformity for target volume, and delivered fewer doses to ipsilateral lens and eyeballs compared with CRT. However, VMAT and IMRT increased the low dose volume to the contralateral OARs. Although VMAT and IMRT showed mixed results on target coverage and OAR sparing, VMAT decreased MU and delivery time significantly compared with IMRT. VMAT is a promising and feasible external beam radiotherapy technique in the treatment of intraocular cancer patients.

Nasopharyngeal cancer (NPC) is a malignant epithelial carcinoma of the head and neck. Cancer therapy targeting programmed cell death protein-1 (PD-1) or programmed death ligand-1 (PD-L1) is revolutionary. However, the tumorigenic mechanism of PD-L1 is not yet clear in NPC. Here we demonstrated an oncogenic role of PD-L1 via activating PI3K/AKT in NPC cells. PD-L1 overexpression was frequently detected in NPC biopsies and cell lines by qRT-PCR. PD-L1 overexpression and knockdown demonstrated that PD-L1 promoted NPC cell invasion and metastasis in vitro and in vivo. Mechanistically, PD-L1 prominently activated the epithelial-mesenchymal transition (EMT) process in a PI3K/AKT-dependent manner. Taken together, we found that PD-L1 overexpression confers NPC cell malignancy and aggressiveness via activating the downstream PI3K/AKT signaling. Thus, these results provide a basis for diagnosis and treatment of NPC. [ABSTRACT FROM AUTHOR]

Dynamic myocardial perfusion CT (DMP-CT) imaging provides quantitative functional information for diagnosis and risk stratification of coronary artery disease by calculating myocardial perfusion hemodynamic parameter (MPHP) maps. However, the level of radiation delivered by dynamic sequential scan protocol can be potentially high. The purpose of this work is to develop a pre-contrast normal-dose scan induced structure tensor total variation regularization based on the penalized weighted least-squares (PWLS) criteria to improve the image quality of DMP-CT with a low-mAs CT acquisition. For simplicity, the present approach was termed as ‘PWLS-ndiSTV’. Specifically, the ndiSTV regularization takes into account the spatial-temporal structure information of DMP-CT data and further exploits the higher order derivatives of the objective images to enhance denoising performance. Subsequently, an effective optimization algorithm based on the split-Bregman approach was adopted to minimize the associative objective function. Evaluations with modified dynamic XCAT phantom and preclinical porcine datasets have demonstrated that the proposed PWLS-ndiSTV approach can achieve promising gains over other existing approaches in terms of noise-induced artifacts mitigation, edge details preservation, and accurate MPHP maps calculation. [ABSTRACT FROM AUTHOR]