Objective.Develop an anatomical model based on the statistics of the population data and evaluate the model for anatomical robust optimisation in head and neck cancer proton therapy.Approach.Deformable image registration was used to build the probability model (PM) that captured the major deformation from patient population data and quantified the probability of each deformation. A cohort of 20 nasopharynx patients was included in this retrospective study. Each patient had a planning CT and 6 weekly CTs during radiotherapy. We applied the model to 5 test patients. Each test patient used the remaining 19 training patients to build the PM and estimate the likelihood of a certain anatomical deformation to happen. For each test patient, a spot scanning proton plan was created. The PM was evaluated using proton spot location deviation and dose distribution.Main results. Using the proton spot range, the PM can simulate small non-rigid variations in the first treatment week within 0.21 ± 0.13 mm. For overall anatomical uncertainty prediction, the PM can reduce anatomical uncertainty from 4.47 ± 1.23 mm (no model) to 1.49 ± 1.08 mm at week 6. The 95% confidence interval (CI) of dose metric variations caused by actual anatomical deformations in the first week is -0.59% ∼ -0.31% for low-risk CTD95, and 0.84-3.04 Gy for parotidDmean. On the other hand, the 95% CI of dose metric variations simulated by the PM at the first week is -0.52 ∼ -0.34% for low-risk CTVD95, and 0.58 ∼ 2.22 Gy for parotidDmean.Significance.The PM improves the estimation accuracy of anatomical uncertainty compared to the previous models and does not depend on the acquisition of the weekly CTs during the treatment. We also provided a solution to quantify the probability of an anatomical deformation. The potential of the model for anatomical robust optimisation is discussed.

Photobiomodulation therapy (PBMT) is the use of red or near-infrared light to heal, restore, and stimulate physiological processes that repair damage caused by trauma or a disease. PBMT is widely used in sports injuries, arthritis, neuropathic pain, and back and neck pain. In recent years, PBMT is a safe and effective tool for toxic reactions associated with cancer treatment, such as oral mucositis in patients undergoing chemo-radiotherapy for head and neck cancer or stem cell transplantation, radiation-associated dry mouth, taste disorders, radiation dermatitis, post-radiotherapy fibrosis, and lymphedema associated with head and neck cancer and breast cancer. However, the equipment and optimal dosimetric parameters for PBMT have not been fully defined and need to be further explored.

Objective To quantify the setup errors for the different anatomical sites of patients who received intensity-modulated radiotherapy (IMRT) with linear accelerator on-board kilovolt fan beam CT(kV-FBCT) as non-isocenter IGRT and megavolt cone beam CT (MV-CBCT) as isocenter IGRT. Methods A retrospective analysis was performedon 70 patients who underwent radiotherapy, kV-FBCT, and/or MV-CBCT scans after each routine setup prior to IMRT. The average displacement (M), systematic error (Σ), and random error (б) at different treatment sites in the left-right, anterior-posterior, and cranial-caudal directions were calculated according to the individual displacements. The formula 2.5Σ+0.7б was used to estimate the PTV margin in respective direction. For each single patient, the root mean square in three directions was used as 3D displacement. Results A total of 1130 displacements were recorded in the 70 patients. The PTV margin was estimated to be 1.9-3.1 mm in head and neck cancer, 2.8-5.1 mm in thoracic cancer, 4.6-5.1 mm in breast cancer, 3.0-5.5 mm in upper abdominal cancer, and 3.5-6.8 mm in pelvic tumor. For the 3D mean displacements, the head and neck, thoracic, breast, upper abdominal, and pelvic cancer were 2.4±1.0, 4.0±1.6, 4.1±2.0, 4.6±2.1, and 4.6±2.1 mm, respectively. The average 3D displacement obtained by kV-FBCT and MV-CBCT were 4.1 and 3.4 mm, respectively (P=0.212). Conclusion The quantitative setup-error data can be obtained using linear accelerator on-board FBCT, and the non-isocenter IGRT induced set-up error cannot be negligible.

Purpose: To demonstrate predictive anatomical modelling for improving the clinical workflow of adaptive intensity-modulated proton therapy (IMPT) for head and neck cancer.Methods: 10 radiotherapy patients with nasopharyngeal cancer were included in this retrospective study. Each patient had a planning CT, weekly verification CTs during radiotherapy and predicted weekly CTs from our anatomical model. Predicted CTs were used to create predicted adaptive plans in advance with the aim of maintaining clinically acceptable dosimetry. Adaption was triggered when the increase in mean dose (Dmean) to the parotid glands exceeded 3 Gy(RBE). We compared the accumulated dose of two adaptive IMPT strategies: 1) Predicted plan adaption: One adaptive plan per patient was optimised on a predicted CT triggered by replan criteria. 2) Standard replan: One adaptive plan was created reactively in response to the triggering weekly CT.Results: Statistical analysis demonstrates that the accumulated dose differences between two adaptive strategies are not significant (p > 0.05) for CTVs and OARs. We observed no meaningful differences in D95 between the accumulated dose and the planned dose for the CTVs, with mean differences to the high-risk CTV of -1.20 %, -1.23 % and -1.25 % for no adaption, standard and predicted plan adaption, respectively. The accumulated parotid Dmean using predicted plan adaption is within 3 Gy(RBE) of the planned dose and 0.31 Gy(RBE) lower than the standard replan approach on average.Conclusion: Prediction-based replanning could potentially enable adaptive therapy to be delivered without treatment gaps or sub-optimal fractions, as can occur during a standard replanning strategy, though the benefit of using predicted plan adaption over the standard replan was not shown to be statistically significant with respect to accumulated dose in this study. Nonetheless, a predictive replan approach can offer advantages in improving clinical workflow efficiency.(c) 2022 The Author(s). Published by Elsevier B.V. Radiotherapy and Oncology 173 (2022) 93-101 This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

The aim of this study was to investigate the therapeutic value of neoadjuvant chemotherapy for breast cancer (BC) based on magnetic resonance imaging (MRI) and to evaluate its effect on depressive mood and immune function in patients. 70 female patients with BC who received neoadjuvant chemotherapy were selected for the experiment to comprehensively evaluate the MRI image findings, immune cell levels before and after chemotherapy, as well as the depression score and influencing factors of the patients during chemotherapy. The results showed that 49 patients (70%) responded to treatment, and MRI showed that the breast mass after chemotherapy was significantly reduced. 55 patients experienced depressive mood during chemotherapy, and the incidence of depression was 78.5%. Adverse symptoms such as pain, worry, sadness, vertigo, and nausea are important factors in the development of depression in patients. However, there were no significant changes in the levels of CD4+, CD8+, CD4+/CD8+, and killer cells before and after chemotherapy, and only B cells showed a significant decrease (9.78 ± 3.65% and 7.63 ± 3.65%) (P < 0.05). In summary, neoadjuvant chemotherapy can effectively shrink the breast mass and provide favorable conditions for subsequent surgery, and its clinical efficacy can be more accurately assessed by MRI. Neoadjuvant chemotherapy has little effect on the immune function of patients, but it will promote patients to experience depression. It provides a reference for the clinical treatment and prognosis of BC patients.

ABSTRACT PURPOSE We aimed to quantify the sublocal geometric uncertainties of the neck prophylactic clinical target volume (CTV prophy ) during image-guided radiotherapy for nasopharyngeal cancer (NPC). MATERIALS AND METHODS Twenty patients with locally advanced NPC underwent one planning computed tomography (CT plan ) followed by six weekly CT (CT repeat ) scans during chemotherapy and intensity-modulated radiation therapy. The sternocleidomastoid muscle (SCM) and its anterior, middle, and posterior parts, as well as the body contours at the 1 st (C1) and 2 nd (C2) cervical vertebrae, hyoid bone (HB), and cricoid cartilage (CC) in transverse CT sections, were manually delineated in the CT plan and each CT repeat . The residual error and 2D or 3D vector displacements of each sublocation were calculated, and the planning target volume (PTV) margins were estimated using the PTV margin formula. RESULTS The left- and right-sided SCM volume decreased by 3.7 ± 9.6% (1.9–5.4%) and 5.1 ± 6.7% (3.9–6.3%), respectively, and the center of mass shifted medially 0.8–0.9 mm. An anisotropic PTV margin of 2–4 and 1–5 mm was needed in the left-right and anterior-posterior directions, respectively. The geometric changes in the upper neck at the C1 and C2 sections were smaller than those in the middle-lower neck at the HB and CC levels. At the same sublocation, the margin needed in the anterior-middle part was smaller than that needed in the posterior part of the neck. The rigid imaging registration-induced anatomical errors in the upper neck were < 1.9%, and those in the middle and lower neck level were 0.6–3.8%. CONCLUSIONS The surface geometrical changes of the neck prophylactic CTV in the sublocations are substantial and an anisotropic PTV margin of 1–5 mm is needed in the context of image-guided radiotherapy for NPC.

Objective . We proposed two anatomical models for head and neck patients to predict anatomical changes during the course of radiotherapy. Approach . Deformable image registration was used to build two anatomical models: (1) the average model (AM) simulated systematic progressive changes across the patient cohort; (2) the refined individual model (RIM) used a patient’s CT images acquired during treatment to update the prediction for each individual patient. Planning CTs and weekly CTs were used from 20 nasopharynx patients. This dataset included 15 training patients and 5 test patients. For each test patient, a spot scanning proton plan was created. Models were evaluated using CT number differences, contours, proton spot location deviations and dose distributions. Main results . If no model was used, the CT number difference between the planning CT and the repeat CT at week 6 of treatment was on average 128.9 Hounsfield Units (HU) over the test population. This can be reduced to 115.5 HU using the AM, and to 110.5 HU using the RIM 3 (RIM, updated at week (3). When the predicted contours from the models were used, the average mean surface distance of parotid glands can be reduced from 1.98 (no model) to 1.16 mm (AM) and 1.19 mm (RIM 3 ) at week 6. Using the proton spot range, the average anatomical uncertainty over the test population reduced from 4.47 ± 1.23 (no model) to 2.41 ± 1.12 mm (AM), and 1.89 ± 0.96 mm (RIM 3 ). Based on the gamma analysis, the average gamma index over the test patients was improved from 93.87 ± 2.48 % (no model) to 96.16 ± 1.84% (RIM 3 ) at week 6. Significance . The AM and the RIM both demonstrated the ability to predict anatomical changes during the treatment. The RIM can gradually refine the prediction of anatomical changes based on the AM. The proton beam spots provided an accurate and effective way for uncertainty evaluation.

Background Considerable geometric changes to the organs at risk (OARs) have been reported during treatment with chemotherapy and intensity modulated radiotherapy (chemo-IMRT) for locally advanced nasopharyngeal carcinoma (LA-NPC). This study aimed to quantify geometric changes to the central nervous system-related OARs (CNS-OARs), during chemo-IMRT for LA-NPC.Methods This prospective study included 20 patients with LA-NPC, treated with chemo-IMRT. Patients underwent a planning computed tomography (CT-plan) scan with intravenous contrast, followed by six weekly scans without contrast (CT-rep). For CNS-OARs, including the spinal cord, brainstem, optic chiasm and nerves, the globes of the eye, lens, and inner ears, their volume loss, the center of mass (COM) displacement, and spatial deformation was compared among weeks, respectively. The correlation between organ volume reduction and patients’ weight loss was estimated.Results The volume of the brainstem, spinal cord, and the globe of left-and right-side eye averagely decreased by 2.6±2.3% (95% CI: 2.1%, 3.1%), 6.5±4.8% (5.6%,7.4%), 9.4±6.9% (8.1%, 10.6%) and 9.6±7.8% (8.2, 11.1%) respectively. The volume reduction of the spinal cord and that of the brainstem were significantly correlated with patients’ weight loss. For all OARs, the COM displacement was within 3 mm, except for the lower level of the spinal cord. The DSC value of the spinal cord, brainstem, and the globes of the eye was of >0.85 throughout treatment.Conclusions The volume and shape changes to the CNS-OARs during chemo-IMRT for NPC were quantifiable, which could be useful to refine radiation treatment protocols.### Competing Interest StatementThe authors have declared no competing interest.### Funding StatementThis research was funded by National Natural Science Funding of China (81974462)### Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:The study was conducted in accordance with the Declaration of Helsinki, and approved by the Institutional Review Board for the Hubei Cancer Hospital (No. 2010V011, Aug. 19, 2010).I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesThe datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Background: Intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) acts on the tumor and affects surrounding organs at risk (OARs). This study aimed to quantify the geometric changes in the parotid gland, the submandibular gland (SMG), and the thyroid, during the course of treatment. Methods: Twenty patients diagnosed with locally advanced NPC were consecutively enrolled, and received definitive chemoradiotherapy in 33 fractions over 6.5 weeks. Each patient underwent planning computed tomography (pCT) followed by six weekly repeat CTs (rCTs) without contrast enhancement. Each rCT was rigidly registered to its pCT. Changes in terms of volume, position, and shape of the OARs were assessed. Differences in left- and right-sided OARs were compared. Results: Radiation doses to the parotid, SMG, and thyroid were 32.12 ± 11.2 Gy (mean ± standard deviation SD), 25.46 ± 8.62 Gy, and 18.89 ± 10.24 Gy, respectively. Volume reductions of 28.6% ± 14.6% (mean ± SD), 26.6% ± 17.1%, and 12.3% ± 11.3% were observed in the parotid, SMG, and thyroid, respectively. Rate of volume loss for the parotid and SMG decreased from 1.6-1.7% per day in the first week to 0.5%-0.6% in the last week. Contrarily, not all thyroid lobes decreased in volume during treatment. The center of mass of the parotid shifted 2.0-2.6 mm medially; for the SMG and thyroid, a 0.1-0.5 mm medial shift was noted. The displacement in the anterior-posterior and cranial-caudal directions was < 0.6 mm. The 3-dimensional vector displacements of the parotid and SMG were 2.2-2.9 mm, and that of thyroid was 4.0-4.3 mm. The overlapping metrics of all three OARs decreased over time, and the shortest perpendicular distance increased from 1.5-1.8 mm in the first week to 2.4-2.5 mm in the last week. The geometric differences between weeks were statistically significant (P<0.05). Conclusions: The volume, position, and shape of the OARs changed significantly during IMRT for NPC. These geometric changes displayed a time association, suggesting the necessity to re-plan treatment for better sparing of these OARs.

Background Colorectal cancer (CRC) ranks the third among the most common malignancies globally. It is well known that microRNAs (miRNAs) play vital roles in destabilizing mRNAs and repressing their translations in this disease. However, the mechanism of miRNA-induced mRNA cleavage remains to be investigated. Method In this study, high-throughput small RNA (sRNA) sequencing was utilized to identify and profile miRNAs from six pairs of colorectal cancer tissues (CTs) and adjacent tissues (CNs). Degradome sequencing (DS) was employed to detect the cleaved target genes. The Database for Annotation, Visualization and Integrated Discovery (DAVID) software was used for GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis. Results In total, 1278 known miRNAs (clustered into 337 families) and 131 novel miRNAs were characterized in the CT and CN libraries, respectively. Of those, 420 known and eight novel miRNAs were defined as differentially expressed miRNAs (DEmiRNAs) by comparing the expression levels observed in the CT and CN libraries. Furthermore, through DS, 9685 and 202 potential target transcripts were characterized as target genes for 268 known and 33 novel miRNAs, respectively. It was further predicted that a total of 264 targeted genes for the 85 DEmiRNAs are involved in proteoglycans in cancer and the AMP-activated protein kinase signaling pathway. After systemic analysis of prognosis-related miRNA targets in those cancer-related signal pathways, we found that two targets ezrin (EZR) and hematopoietic cell-specific Lyn substrate 1 (HCLS1) had the potential prognostic characteristics with CRC regarding over survival (OS) or recurrence. Conclusion In total, we found that endonucleolytic miRNA-directed mRNA cleavage occurs in CRC. A number of potential genes targeted by CRC-related miRNAs were identified and some may have the potential as prognosis markers of CRC. The present findings may lead to an improved better appreciation of the novel interaction mode between miRNAs and target genes in CRC.

BACKGROUND:Colorectal Cancer (CRC) is a highly heterogeneous disease. RNA profiles of bulk tumors have enabled transcriptional classification of CRC. However, such ways of sequencing can only target a cell colony and obscure the signatures of distinct cell populations. Alternatively, single-cell RNA sequencing (scRNA-seq), which can provide unbiased analysis of all cell types, opens the possibility to map cellular heterogeneity of CRC unbiasedly.METHODS:In this study, we utilized scRNA-seq to profile cells from cancer tissue of a CRC patient. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to understand the roles of genes within the clusters.RESULTS AND CONCLUSION:The 2824 cells were analyzed and categorized into 5 distinct clusters by scRNA-seq. For every cluster, specific cell markers can be applied, indicating each 1 of them different from another. We discovered that the tumor of CRC displayed a clear sign of heterogenicity, while genes within each cluster serve different functions. GO term analysis also stated that different cluster's relatedness towards the tumor of CRC differs. Three clusters participate in peripheral works in cells, including, energy transport, extracellular matrix generation, etc; Genes in other 2 clusters participate more in immunology processes. Lastly, trajectory plot analysis also supports the viewpoint, in that some clusters present in different states and pseudo-time, while others present in a single state or pseudo time. Our analysis provides more insight into the heterogeneity of CRC, which can provide assistance to further researches on this topic.

0 Introduction Onco-cardiology (also known as Cardio-oncology) is defined as the medical specialty focused on the management of cardiovascular diseases in cancer patients.Significant progress has been achieved in the last several decades in the prevention,early detection,and treatment of both cardiac and oncologic diseases.Despite these advances,these two medical conditions continue to constitute the most common causes of deaths in the developed countries and although cancer remains a leading cause of morbidity and mortality worldwide,the survival rate of patients with malignancy has steadily increased over the last 4 decades.The 5-year relative survival rate of these patients increased from around 50％ between 1975 and 1977 to around 68％ between 1999 and 2005[1].In the USA alone,around 14.5 million cancer survivors were alive in 2014 and it is estimated that by 2024,the population of cancer survivors will be close to 19 million[2].

Background: Circulating endothelial cells (CECs) and their subpopulations could be potential novel biomarkers for various malignancies. However, reliable enumerable methods are warranted to further improve their clinical utility. This study aimed to optimize a flow cytometric method (FCM) assay for CECs and subpopulations in peripheral blood for patients with solid cancers. Patients and methods: An FCM assay was used to detect and identify CECs. A panel of 60 blood samples, including 44 metastatic cancer patients and 16 healthy controls, were used in this study. Some key issues of CEC enumeration, including sample material and anticoagulant selection, optimal titration of antibodies, lysis/wash procedures of blood sample preparation, conditions of sample storage, sufficient cell events to enhance the signal, fluorescence-minus-one controls instead of isotype controls to reduce background noise, optimal selection of cell surface markers, and evaluating the reproducibility of our method, were integrated and investigated. Wilcoxon and Mann-Whitney U tests were used to determine statistically significant differences. Results: In this validation study, we refined a five-color FCM method to detect CECs and their subpopulations in peripheral blood of patients with solid tumors. Several key technical issues regarding preanalytical elements, FCM data acquisition, and analysis were addressed. Furthermore, we clinically validated the utility of our method. The baseline levels of mature CECs, endothelial progenitor cells, and activated CECs were higher in cancer patients than healthy subjects (P<0.01). However, there was no significant difference in resting CEC levels between healthy subjects and cancer patients (P=0.193). Conclusion: We integrated and comprehensively addressed significant technical issues found in previously published assays and validated the reproducibility and sensitivity of our proposed method. Future work is required to explore the potential of our optimized method in clinical oncologic applications.

Black phosphorus quantum dots are incorporated into liposomal bilayers to produce a drug delivery system with excellent near-infrared (NIR) photothermal properties and drug release capability controlled by light. In vitro experiments demonstrate its good biocompatibility and NIR-light-induced chemo-photothermal antitumor efficiency.

Neoadjuvant therapy (NAT) has been used increasingly in patients with locally advanced or early-stage breast cancer. However, the accurate evaluation and prediction of response to NAT remain the great challenge. Biomarkers could prove useful to identify responders or nonresponders, or even to distinguish between early and delayed responses. These biomarkers could include markers from the tumor itself, such as versatile proteins, genes, and ribonucleic acids, various biological factors or peripheral blood cells, and clinical and pathological features. Possible predictive markers could also include multiple features from functional imaging, such as standard uptake values in positron emission tomography, apparent diffusion coefficient in magnetic resonance, or radiomics imaging biomarkers. In addition, cells that indirectly present the immune status of tumor cells and/or their host could also potentially be used as biomarkers, eg, tumor-infiltrating lymphocytes, tumor-associated macrophages, and myeloid-derived suppressor cells. Though numerous biomarkers have been widely investigated, only estrogen and/or progesterone receptors and human epidermal growth factor receptor have been proven to be reliable biomarkers to predict the response to NAT. They are the only biomarkers recommended in several international guidelines. The other aforementioned biomarkers warrant further validation studies. Some multigene profiling assays that are commercially available, eg, Oncotype DX and MammaPrint, should be used with caution when extrapolated to NAT settings. A panel of combined multilevel biomarkers might be able to predict the response to NAT more robustly than individual biomarkers. To establish such a panel and its prediction model, reliable methods and extensive clinical validation are warranted.

BACKGROUND:To quantify the geometrical changes of each neck nodal level (NNL) and estimate the geometric planning target volume (PTV) margin during image-guided radiotherapy (IGRT) for nasopharyngeal cancer (NPC). METHODS:Twenty patients with locally advanced NPC underwent one planning computed tomography (CTplan) and 6 weekly repeat CT (CTrep) scans during chemoradiotherapy. Each CTrep was rigidly registered to the CTplan. All the NNLs were manually delineated in each transverse CT section. When comparing the NNL in CTrep with CTplan, their volumes, displacement of the center of the mass, and the shortest perpendicular distance (SPD) were automatically calculated. This was followed by calculation of the systematic and random errors, overlapping index (OI), and dice similarity coefficient (DSC). With PTVs isotropically expanded from NNL by 1, 2, 3, 4, and 5 mm, they were compared with NNL itself; OI >0.95 was defined as the acceptable geometrical coverage. The Mann-Whitney test was used for statistical analysis. RESULTS:All volumes, OI, and DSC of the NNLs (not including level IA) showed a linear decrease over time throughout the treatment course. The volume of NNLs decreased by 1-6% in the first week and 10-21% in the sixth week. The mean SPD was 1.3-1.7 and 1.9-3.5 mm in the first and sixth week respectively. The DSCs for nodal level IB, II, III, and IV were >0.7 and that of level V was <0.7 throughout the treatment course. For level IA and VI, DSC was <0.7 after the 2nd week. To maintain the OI >0.95, 2-5 mm was needed to expand the different NNLs. CONCLUSIONS:The geometrical changes of each NNL are substantial and the necessary margin of 2-5 mm depended on individual NNL is needed to maintain geometrical coverage throughout the course of IGRT for NPC.

Angiogenesis contributes to the growth of solid tumors. Antiangiogenic agents are widely used in various cancers and considerable efforts have been made in the development of novel biomarkers that can predict the outcome of an anticancer treatment. Of those, circulating endothelial cells (CECs) and their subsets constitute a surrogate tool for monitoring disease activity. However, owing to the lack of standardization on the phenotypes and detection of CECs and their subsets, results have always been inconsistent and uninterpretable. In this review, we focus on the biological characteristics in terms of physiology, phenotypes and detection of CECs along with their subsets; review the current scenario of CEC enumeration as a surrogate biomarker in clinical oncology; and explore their future potential applications.

Approximately 25–30% of patients with cancer undergo thoracic radiation therapy (RT). RT might inadvertently induce heart injury and result in various forms of radiation-related heart disease (RRHD). The main endpoints of RRHD include cardiac death from RT, clinical heart disease (congestive heart disease, ischemic heart disease, and myocardial infarction), and subclinical heart disease (cardiac perfusion defects). Advanced RT techniques, such as breath control, intensity-modulated RT, and image-guided RT, as well as limited target volume definition might spare or avoid cardiac doses and/or volume, which may translate into decreased incidence of RRHD. The total delivered radiation dose to cardiac implantable electronic devices was strongly recommended not to exceed 2 Gy. The treatment strategies of RRHD were based on the various recommended consensus of related heart diseases in cardiology. However, the standardized definitions of the cardiac structures, dose-volume limits during radiation planning design, the optimal dose-volume parameters, and the dose-volume effects of various cardiac substructures warrant further investigation. The recognition, prediction, prevention, and management of RRHD require close collaboration between oncologists and cardiologists.

Both the tumor and organs at risk (OARs) occurred considerable changes during the intensity modulated radiation therapy (IMRT) course for nasopharyngeal carcinoma (NPC). This study aims to analyze quantitatively the geometrical variations of the parotid, submandibular gland (SMG) and thyroid as three independent OARs throughout IMRT course. Twenty NPC patients received the definitive chemoIMRT in 33 fractions within 6.5 week-long course. Each patient had a planning CT (pCT) and six weekly repeat CT (rCT) without enhanced contrast. Each rCT was rigidly registered to its pCT. The parotid, SMG and thyroid were manually delineated in the axial pCT and rCT imaging by a single radiation oncologist. When compared a contour in pCT with rCT, it was calculated the volume of each contour (V_pCT, V_rCT), the common volume (V_com) and the shortest perpendicular distance (SPD) between two contours. Each surface voxel of a contour in rCT has a SPD and the standard deviation (SD) of all the SPDs was calculated. Both the SPD and Dice similarity coefficient (DSC) calculated as 2*V_com / (V_pCT + V_rCT) were used as the surrogate of the shape variations. The displacement of center of mass as the positional shift was calculated and the mean displacement, system and random error were statistically calculated. The difference of geometrical changes among six week, the left- and right- sided OAR was compared using one-way analysis of variance or Mann-Whitney U test. The mean radiation dose of the parotid, SMG, thyroid gland were 32.12 ± 11.2 Gy, 25.46 ± 8.62 Gy, 18.89 ± 10.24 Gy, (mean ± standard deviation) respectively. And their mean and maximal volume reduction were 28.6% ± 14.6%, 26.6% ± 17.1%, 12.3% ± 11.3% and 40.6% ± 12.4%, 38.9% ± 14.9%, 16.3% ± 14.3%, respectively. For the parotid and SMG, the volume loss per treatment day decreased from 1.7%, 1.6% in the first week to 0.5%, 0.6% in the last week, and that of thyroid was of 0.4% - 0.5% after the 2nd week. The center of mass displacement of parotid gland shifted medially 2.0 mm - 2.6 mm, SMG and thyroid did medially 0.1 mm - 0.5 mm. In addition, the displacement in anterior-posterior and cranial-caudal direction were < 0.6 mm. The 3-demensional vector displacements of the parotid and SMG were 2.2 mm – 2.9 mm and that of thyroid were 4.0 mm - 4.3 mm. The DSCs of parotid, SMG and thyroid showed the decreased time-trend. For the parotid, SMG, thyroid, the SD of SPDs increased from 1.5 mm – 1.8 mm in the first week to 2.1 mm – 2.5 mm. The variations among the different weeks were statistically different (P < 0.05) and there was no difference between the left- and right-sided OARs (P> 0.05). For NPC, the volume, position and shape of parotid, SMG, thyroid occurred in quantifiable variations and these geometrical changes have their time-trend, which suggests the necessity of re-planning for the further sparing of OAR further during IMRT.

目的 比较同期推量放射治疗(SIB)和全脑照射+三维适形放射治疗(WBRT+ 3D-CRT)序贯治疗在肺癌脑转移患者中的应用效果.方法 收集2006年1月至2011年4月间152例患者行SIB(研究组),146例肺癌脑转移瘤患者行WBRT+ 3D-CRT序贯治疗(对照组),比较两组患者的临床效果.结果 研究组患者的客观缓解率、疾病控制率和1年生存率均高于对照组,差异均有统计学意义(均P＜0.05).研究组患者中位无进展生存时间明显延长,与对照组差异有统计学意义(P＜0.05).结论 SIB能提高肺癌脑转移瘤患者的客观缓解率、疾病控制率和1年生存率,同时能延长中位生存时间.