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2022 ◽  
Vol 12 ◽  
Author(s):  
Michaela Schuermann ◽  
Yvonne Dzierma ◽  
Frank Nuesken ◽  
Joachim Oertel ◽  
Christian Rübe ◽  
...  

BackgroundNavigated transcranial magnetic stimulation (nTMS) of the motor cortex has been successfully implemented into radiotherapy planning by a number of studies. Furthermore, the hippocampus has been identified as a radiation-sensitive structure meriting particular sparing in radiotherapy. This study assesses the joint protection of these two eloquent brain regions for the treatment of glioblastoma (GBM), with particular emphasis on the use of automatic planning.Patients and MethodsPatients with motor-eloquent brain glioblastoma who underwent surgical resection after nTMS mapping of the motor cortex and adjuvant radiotherapy were retrospectively evaluated. The radiotherapy treatment plans were retrieved, and the nTMS-defined motor cortex and hippocampus contours were added. Four additional treatment plans were created for each patient: two manual plans aimed to reduce the dose to the motor cortex and hippocampus by manual inverse planning. The second pair of re-optimized plans was created by the Auto-Planning algorithm. The optimized plans were compared with the “Original” plan regarding plan quality, planning target volume (PTV) coverage, and sparing of organs at risk (OAR).ResultsA total of 50 plans were analyzed. All plans were clinically acceptable with no differences in the PTV coverage and plan quality metrics. The OARs were preserved in all plans; however, overall the sparing was significantly improved by Auto-Planning. Motor cortex protection was feasible and significant, amounting to a reduction in the mean dose by >6 Gy. The dose to the motor cortex outside the PTV was reduced by >12 Gy (mean dose) and >5 Gy (maximum dose). The hippocampi were significantly improved (reduction in mean dose: ipsilateral >6 Gy, contralateral >4.6 Gy; reduction in maximum dose: ipsilateral >5 Gy, contralateral >5 Gy). While the dose reduction using Auto-Planning was generally better than by manual optimization, the radiated total monitor units were significantly increased.ConclusionConsiderable dose sparing of the nTMS-motor cortex and hippocampus could be achieved with no disadvantages in plan quality. Auto-Planning could further contribute to better protection of OAR. Whether the improved dosimetric protection of functional areas can translate into improved quality of life and motor or cognitive performance of the patients can only be decided by future studies.


Author(s):  
Michael J. McKay ◽  
Kim L. Taubman ◽  
Szeting Lee ◽  
Andrew M. Scott

2022 ◽  
Vol 11 ◽  
Author(s):  
Yu-mei Zhang ◽  
Guan-zhong Gong ◽  
Qing-tao Qiu ◽  
Yun-wei Han ◽  
He-ming Lu ◽  
...  

Nasopharyngeal carcinoma (NPC) is a malignant tumor of the head and neck. The primary clinical manifestations are nasal congestion, blood-stained nasal discharge, headache, and hearing loss. It occurs frequently in Southeast Asia, North Africa, and especially in southern China. Radiotherapy is the main treatment, and currently, imaging examinations used for the diagnosis, treatment, and prognosis of NPC include computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET)-CT, and PET-MRI. These methods play an important role in target delineation, radiotherapy planning design, dose evaluation, and outcome prediction. However, the anatomical and metabolic information obtained at the macro level of images may not meet the increasing accuracy required for radiotherapy. As a technology used for mining deep image information, radiomics can provide further information for the diagnosis and treatment of NPC and promote individualized precision radiotherapy in the future. This paper reviews the application of radiomics in the diagnosis and treatment of nasopharyngeal carcinoma.


2022 ◽  
Author(s):  
Stine Nyby ◽  
Signe Hertz Hansen ◽  
Sophie Yammeni ◽  
Agnieszka Monika Delekta ◽  
Gintare Naujokaite ◽  
...  

Abstract Purpose: Breast cancer patients scheduled for postoperative radiotherapy undergo radiotherapy-planning computed tomography (CT), and incidental findings (IFs) may appear. This study investigated the interobserver variability between radiologists and oncologists when assessing IFs on radiotherapy-planning CT scans in breast cancer patients prior to adjuvant radiotherapy. Methods: We included 383 breast cancer patients who underwent planning CT at the Aalborg University Hospital between February 1, 2017 and February 28, 2018. IFs noted by the oncologists were identified from medical records. Two specialized radiologists reviewed the scans and described their IFs. IFs were classified as benign or potential malignant lesions. Cohen’s kappa statistic was used to measure interobserver agreement.Results: A total of 513 IFs were registered. The radiologists registered 433 findings, and the oncologists noted 80 (1.1 and 0.2 IFs per patient, respectively). Most potential malignant IFs were found in the liver, lungs, bones, and lymph nodes. The radiologists and oncologists detected potential malignant lesions in 94 (25%) and 34 (9%) patients, respectively. The oncologists’ sensitivity for detecting IFs in the liver and lungs were 29% and 20%, respectively. The agreements on IFs in the liver and lungs were fair (Cohen’s kappa values of 0.33 and 0.28, respectively).Conclusion: Radiologists reported a significantly higher frequency of IFs and potential malignant lesions than oncologists. Additionally, the oncologists had a low sensitivity when reporting IFs in both the liver and lungs. These results emphasize the need for specialized radiologists to scrutinize planning CT scans of breast cancer patients to ensure the intention to treat.


2022 ◽  
Author(s):  
K. Harrison ◽  
H. Pullen ◽  
C. Welsh ◽  
O. Oktay ◽  
J. Alvarez-Valle ◽  
...  

2022 ◽  
Vol 355 ◽  
pp. 03022
Author(s):  
Linghao Du ◽  
Rui Wang ◽  
Lin Cui ◽  
Xiaolin Min ◽  
Qingyi Liu ◽  
...  

Automatic body region localization in medical three-dimensional (3D)-CT images is a critical step of computerized body-wide Automatic Anatomy Recognition (AAR) system, which can be applied for radiotherapy planning and interest slices retrieving. Currently, the complex internal structure of human body and time consuming computation are the main challenges for the localization. Therefore, this paper introduces and improves the YOLO-v3 model into the body region localization for these problems. First, seven categories of body regions in a CT volume image I are defined based on the modification version of our previous work. Second, an improved YOLO-v3 model is trained to classify each axial slice into one of the seven categories. Then, the effectiveness of the proposed method is evaluated on 3D-CT images that collected from 220 subjects. The experimental results demonstrate that the slice localizing error is less than 3 NoS (Number of slices), which is competitive to the state-of-the-art methods. Beyond this, our method is simple and computationally efficient owing to its less training time, and the average computational time for localizing a volume CT images is about 3 second, which shows potential for a further application.


Author(s):  
Kevin Chiu ◽  
Peter Hoskin ◽  
Amit Gupta ◽  
Roeum Butt ◽  
Samsara Terparia ◽  
...  

Objectives: Radiologist input in peer review of head and neck radiotherapy has been introduced as a routine departmental approach. The aim was to evaluate this practice and to quantitatively analyse the changes made. Methods: Patients treated with radical-dose radiotherapy between August–November 2020 were reviewed. The incidence of major and minor changes, as defined by The Royal College of Radiologists guidance, was prospectively recorded. The amended radiotherapy volumes were compared with the original volumes using Jaccard Index (JI) to assess conformity; Geographical Miss Index (GMI) for under contouring; and Hausdorff Distance (HD) between the volumes. Results: In total 73 out of 87 (84%) patients were discussed. Changes were recommended in 38 (52%) patients: 30 had ≥1 major change, eight had minor changes only. There were 99 amended volumes: The overall median JI, GMI and HD was 0.91 (interquartile range [IQR]=0.80–0.97), 0.06 (IQR = 0.02–0.18) and 0.42 cm (IQR = 0.20–1.17 cm) respectively. The nodal gross-tumour-volume (GTVn) and therapeutic high-dose nodal clinical-target-volume (CTVn) had the biggest magnitude of changes: The median JI, GMI and HD of GTVn was 0.89 (IQR = 0.44–0.95), 0.11 (IQR = 0.05–0.51), 3.71 cm (IQR = 0.31–6.93 cm); high-dose CTVn was 0.78 (IQR = 0.59–0.90), 0.20 (IQR = 0.07–0.31) and 3.28 cm (IQR = 1.22–6.18 cm) respectively. There was no observed difference in the quantitative indices of the 85 ‘major’ and 14 ‘minor’ volumes (p = 0.5). Conclusions: Routine head and neck radiologist input in radiotherapy peer review is feasible and can help avoid gross error in contouring. Advances in knowledge: The major and minor classification may benefit from differentiation with quantitative indices but requires correlation from clinical outcomes.


Cancers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 6106
Author(s):  
Kerstin Michalski ◽  
Lars Kemna ◽  
Jasmin Asberger ◽  
Anca L. Grosu ◽  
Philipp T. Meyer ◽  
...  

Background: Positron emission tomography (PET)/computed tomography (CT) using the gastrin-releasing peptide receptor antagonist [68Ga]RM2 has shown to be a promising imaging method for primary breast cancer (BC) with positive estrogen receptor (ER) status. This study assessed tumor visualization by [68Ga]RM2 PET/CT in patients with pre-treated ER-positive BC and suspected metastases. Methods: This retrospective pilot study included eight female patients with initial ER-positive, pre-treated BC who underwent [68Ga]RM2 PET/CT. Most of these patients (seven out of eight; 88%) were still being treated with or had received endocrine therapy. [68Ga]RM2 PET/CTs were visually analyzed by two nuclear medicine specialists in consensus. Tumor manifestations were rated qualitatively (i.e., RM2-positive or RM2-negative) and quantitatively using the maximum standardized uptake value (SUVmax). SUVmax values were compared between the two subgroups (RM2-positive vs. RM2-negative). Results: Strong RM2 binding was found in all metastatic lesions of six patients (75%), whereas tracer uptake in all metastases of two patients (25%) was rated negative. Mean SUVmax of RM2-positive metastases with the highest SUVmax per patient (in lymph node and bone metastases; 15.8 ± 15.1 range: 3.7–47.8) was higher than mean SUVmax of the RM2-negative metastases with the highest SUVmax per patient (in bone metastases; 1.6 ± 0.1, range 1.5–1.7). Conclusions: Our data suggest that RM2 binding is maintained in the majority of patients with advanced disease stage of pre-treated ER-positive BC. Thus, [68Ga]RM2 PET/CT could support treatment decision in these patients, radiotherapy planning in oligometastatic patients or selection of patients for RM2 radioligand therapy. Further studies with larger patient cohorts are warranted to confirm these findings.


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