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Background: Intensity modulation with dynamic multi‐leaf collimator (MLC) and monitor unit (MU) changes across control points (CPs) characterizes volumetric modulated arc therapy (VMAT). The increased uncertainty in plan deliverability required patient‐specific quality assurance (PSQA), which remained inefficient upon Quality Assurance (QA) failure. To prevent waste before QA, plan complexity metrics (PCMs) and machine learning models with the metrics were generated, which were lack of providing CP‐specific information upon QA failures. Purpose: By generating 3D images from digital imaging and comminications in medicine in radiation therapy (DICOM RT) plan, we proposed a predictive model that can estimate the deliverability of VMAT plans and visualize CP‐specific regions associated with plan deliverability. Methods: The patient cohort consisted of 259 and 190 cases for left‐ and right‐breast VMAT treatments, which were split into 235 and 166 cases for training and 24 cases from each treatment for testing the networks. Three‐channel 3D images generated from DICOM RT plans were fed into a DenseNet‐based deep learning network. To reflect VMAT plan complexity as an image, the first two channels described MLC and MU variations between two consecutive CPs, while the last channel assigned the beam field size. The network output was defined as binary classified PSQA results, indicating deliverability. The predictive performance was assessed by accuracy, sensitivity, specificity, F1‐score, and area under the curve (AUC). The gradient‐weighted class activation map (Grad‐CAM) highlighted the regions of CPs in VMAT plans associated with deliverability, compared against PCMs by Spearman correlation. Results: The DenseNet‐based predictive model yielded AUCs of 92.2% and 93.8%, F1‐scores of 97.0% and 93.8% and accuracies of 95.8% and 91.7% for the left‐ and right‐breast VMAT cases. Additionally, the specificity of 87.5% for both cases indicated that the predictive model accurately detected QA failing cases. The activation maps significantly differentiated QA failing‐labeled from passing‐labeled classes for the non‐deliverable cases. The PCM with the highest correlation to the Grad‐CAM varied from patient cases, implying that plan deliverability would be considered patient‐specific. Conclusion: This work demonstrated that the deep learning‐based network based on visualization of dynamic VMAT plan information successfully predicted plan deliverability, which also provided control‐point specific planning parameter information associated with plan deliverability in a patient‐specific manner. [ABSTRACT FROM AUTHOR]

Background: Despite the extensive implementation of an organized multidisciplinary team (MDT) approach in cancer treatment, there is little evidence regarding the optimal format of MDT. We aimed to investigate the impact of patient participation in MDT care on the actual application rate of metastasis‐directed local therapy. Methods: We identified all 1211 patients with locally advanced rectal cancer treated with neoadjuvant radiochemotherapy at a single institution from 2006 to 2018. Practice patterns, tumor burden and OMD state were analyzed in recurrent, metastatic cases. Results: With a median follow‐up of 60.7 months, 281 patients developed metastases, and 96 (34.2%), 92 (32.7%), and 93 (33.1%) patients had 1, 2–5, and >5 lesions, respectively. In our study, 27.1% were managed in the MDT clinic that mandated the participation of at least four to five board‐certified multidisciplinary experts and patients in decision‐making processes, while the rest were managed through diverse MDT approaches such as conferences, tumor board meetings, and discussions conducted via phone calls or email. Management in MDT clinic was significantly associated with more use of radiotherapy (p = 0.003) and more sessions of local therapy (p < 0.001). At the time of MDT clinic, the number of lesions was 1, 2–5, and >5 in 9 (13.6%), 35 (53.1%), and 19 (28.8%) patients, respectively. The most common states were repeat OMD (28.8%) and de novo OMD (27.3%), followed by oligoprogression (15%) and induced OMD (10.6%). Conclusion: Our findings suggest that active involvement of patients and radiation oncologists, and surgeons in MDT care has boosted the probability of using local therapies for various types of OMD throughout the course of the disease. [ABSTRACT FROM AUTHOR]

Purpose: Heart toxicity, such as major acute coronary events (ACE), following breast radiation therapy (RT) is of utmost concern. Thus, many studies have been investigating the effect of mean heart dose (MHD) and dose received in heart sub‐structures on toxicity. Most studies focused on the dose thresholds in the heart and its sub‐structures, while few studies adopted such computational methods as deep neural networks (DNN) and radiomics. This work aims to construct a feature‐driven predictive model for ACE after breast RT. Methods: A recently proposed two‐step predictive model that extracts a number of features from a deep auto‐segmentation network and processes the selected features for prediction was adopted. This work refined the auto‐segmenting network and feature processing algorithms to enhance performance in cardiac toxicity prediction. In the predictive model, the deep convolutional neural network (CNN) extracted features from 3D computed tomography (CT) images and dose distributions in three automatically segmented heart sub‐structures, including the left anterior descending artery (LAD), right coronary artery (RCA), and left ventricle (LV). The optimal feature processing workflow for the extracted features was explored to enhance the prediction accuracy. The regions associated with toxicity were visualized using a class activation map (CAM)‐based technique. Our proposed model was validated against a conventional DNN (convolutional and fully connected layers) and radiomics with a patient cohort of 84 cases, including 29 and 55 patient cases with and without ACE. Of the entire 84 cases, 12 randomly chosen cases (5 toxicity and 7 non‐toxicity cases) were set aside for independent test, and the remaining 72 cases were applied to 4‐fold stratified cross‐validation. Results: Our predictive model outperformed the conventional DNN by 38% and 10% and radiomics‐based predictive models by 9% and 10% in AUC for 4‐fold cross‐validations and independent test, respectively. The degree of enhancement was greater when incorporating dose information and heart sub‐structures into feature extraction. The model whose inputs were CT, dose, and three sub‐structures (LV, LAD, and RCA) reached 96% prediction accuracy on average and 0.94 area under the curve (AUC) on average in the cross‐validation, and also achieved prediction accuracy of 83% and AUC of 0.83 in the independent test. On 10 correctly predicted cases out of 12 for the independent test, the activation maps implied that for cases of ACE toxicity, the higher intensity was more likely to be observed inside the LV. Conclusions: The proposed model characterized by modifications in model input with dose distributions and cardiac sub‐structures, and serial processing of feature extraction and feature selection techniques can improve the predictive performance in ACE following breast RT. [ABSTRACT FROM AUTHOR]

Chondroradionecrosis (CRN) is an infrequent phenomenon after definitive RT. The clinical manifestation is usually difficult to distinguish from that of tumor recurrence; however, clinicians should be aware of the possibility of CRN. [ABSTRACT FROM AUTHOR]

We assessed the clinical benefit of combining volumetric‐modulated arc therapy (VMAT) and hypofractionated radiotherapy (HF‐RT) considering the incidence of radiation‐related toxicities. After a retrospective review for breast cancer patients treated with adjuvant RT between 2005 and 2017, a total of 4209 patients treated with three‐dimensional conventional fractionation (CF‐3D, 50.4 Gy/28 fractions) and 1540 patients treated with HF‐RT (768 received HF‐3D; 772, HF‐VMAT; 40 Gy/15 fractions) were included. A total of 2229 patients (38.8%) received regional node irradiation (RNI): 1642 (39.0%), 167 (21.7%) and 420 (54.4%) received RNI via CF‐3D, HF‐3D and HF‐VMAT, respectively. Acute/subacute and late toxicities were evaluated. Propensity scores were calculated via logistic regression. Grade 2+ acute/subacute toxicities was the highest in CF‐3D group (15.0%, 2.6% and 1.6% in CF‐3D, HF‐3D and HF‐VMAT, respectively; P <.001). HF‐VMAT reduced Grade 2+ acute/subacute toxicities significantly compared to CF‐3D (odds ratio [OR] 0.11, P <.001) and HF‐3D (OR 0.45, P =.010). The 3‐year cumulative rate of late toxicities was 18.0% (20.1%, 10.9% and 13.4% in CF‐3D, HF‐3D and HF‐VMAT, respectively; P <.001). On sensitivity analysis, the benefit of HF‐VMAT was high in the RNI group. Acute and late toxicities were fewer after HF‐VMAT than after HF‐3D or CF‐3D, especially in women who underwent RNI. What's new? Hypofractionated radiotherapy (HF‐RT) is increasingly used for whole breast irradiation. However, concerns of possible radiation‐related toxicities persist. Here, in a cohort of breast cancer patients treated with adjuvant RT, the clinical benefits of intensity‐modulated RT (IMRT) with HF were compared with three‐dimensional conventional fractionation (CF‐3D), HF‐3D, and HF volumetric‐modulated arc therapy (HF‐VMAT). Compared to CF‐3D and HF‐3D, a three‐week schedule of 40 Gy in 15 fractions of HF‐VMAT had the lowest rate of radiation‐related acute and late toxicities. HF‐VMAT also had fewer subacute toxicities. The findings indicate that HF‐VMAT can significantly benefit breast cancer patients treated with regional node irradiation. [ABSTRACT FROM AUTHOR]

Background: We investigated the risk of carpal tunnel syndrome (CTS) in diabetic polyneuropathy (DPN).Methods: This study was conducted using records from the National Health Insurance System (NHIS). We divided patients diagnosed with diabetes mellitus (DM) into those with and without DPN. We assessed the effect of DPN on the risk of CTS using Cox proportional hazards regression analyses.Results: DPN was associated with an increased risk of CTS (hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.12-1.58). In sub-analyses, female gender (HR, 1.45; 95% CI, 1.20-1.76), presence of type 2 DM (HR, 1.36; 95% CI, 1.11-1.64), and age 35 to 64 years (HR 1.35; 95% CI, 1.11-1.64) were significantly associated with an increased risk of CTS.Conclusions: Patients with DPN had an increased risk of CTS compared with the non-DPN group, particularly females, those with type 2 DM, and those aged 35 to 64 years. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to determine whether pretreatment 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) volumetric parameters add more prognostic information to p16-positive oropharyngeal squamous cell carcinoma (SCC). Methods We retrospectively analyzed 86 patients with p16-positive oropharyngeal SCC who underwent surgery and postoperative radiotherapy (RT) or chemoradiotherapy (CRT). Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured. Results Higher total MTV (tMTV), nodal MTV (nMTV), and tumor TLG (tTLG) were significantly associated with lower disease-free survival (DFS) (all p < .05) and higher distant metastasis rates (all p < .05). Multivariate analysis of DFS revealed that tMTV ( p = .032), nMTV ( p = .004), and tTLG ( p = .018) were independently significant prognosticators. Conclusion Patients with p16-positive disease with high metabolic tumor burden were associated with higher distant metastasis rates, translating into worse survival. These patients may not be optimal candidates for treatment deintensification. © 2016 Wiley Periodicals, Inc. Head Neck 38: First-1524, 2016 [ABSTRACT FROM AUTHOR]

Aims To determine the utility of FDG- PET in predicting long-term infield tumour control after RT in patients with metastatic hepatocellular carcinoma ( HCC) to bone. Methods Among 223 patients with HCC skeletal metastases diagnosed, we reviewed 22 patients with 45 total sites treated with RT who had at least two FDG- PETs prior to and after RT. The median RT dose was 42 Gy (range, 22-48) with a median fraction of 3 Gy (range, 2-8). Helical tomotherapy was generally offered for lesions that received higher RT dose (36%). The intrahepatic control rate in all patients was 73% at the time of referral. The ratio of tumour SUV to blood-pool activity SUV ( SUV-ratio) was calculated. The primary end-points were infield progression-free survival (infield- PFS) and infield event-free survival (infield- EFS; recurrent and intractable pain or skeletal-related events). Results Among 45 sites, 20 had tumour progression and 21 developed events in the previously treated area. A higher SUV-ratio before RT, SUV-ratio decline and higher radiation dose were independently and significantly correlated with better infield- PFS (both P < 0.05). The tumours with a pre- RT SUV-ratio ≥3.0 and SUV-ratio decline ≥40% had significantly better infield- PFS and EFS than those with either a pre- RT SUV-ratio <3.0 or SUV-ratio decline <40% (both P < 0.05). Conclusions FDG- PET may help to predict outcomes of infield tumour control following palliative RT for treatment of HCC bone metastases. Tumours with low metabolic uptake before RT or with a minor decline in post- RT SUV-ratio showed poor long-term infield tumour control. [ABSTRACT FROM AUTHOR]

Background & Aims Huge (≥10 cm) hepatocellular carcinomas ( HCCs) show dismal prognosis and only a limited number of cases are eligible for curative resection. We studied the therapeutic benefit of radiotherapy ( RT) in patients with huge unresectable HCCs. Methods Data from 283 patients with huge HCCs and preserved liver function who underwent non-surgical treatment from July 2001 to March 2012 were retrospectively reviewed. Patients were divided into 4 groups according to the initial treatment: Group A ( N= 49), transarterial chemoembolization ( TACE); Group B ( N = 35), TACE + RT; Group C ( N = 50), hepatic arterial infusion chemotherapy; and Group D ( n = 149), concurrent chemoradiotherapy ( CCRT). Results and Conclusions The median follow-up period was 27.8 months (range, 12.9-121.9 months). The median overall survival (OS) was longer in Groups B (15.3 months) and D (12.8 months) than in Groups A (7.5 months) and C (8.2 months; Group B vs. A, Bonferroni corrected P [ P c] = 0.04; Group B vs. C, P c = 0.02; Group D vs. A, P c = 0.01; Group D vs. C, P c = 0.006). Groups B and D also showed superior progression-free survival (PFS) and intrahepatic control than Groups A and C. In multivariate analysis, tumour multiplicity, serum alpha-foetoprotein level (≥200 ng/ ml) and initial treatment were independent prognostic factors for OS and PFS. Patients with huge unresectable HCCs treated with RT, either as CCRT or in combination with TACE, showed excellent intrahepatic control and prolonged survival. RT could be considered a promising treatment modality in these patients. [ABSTRACT FROM AUTHOR]