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adaptive radiotherapy

Julie Schatteman, Dirk Van Gestel, Dieter Berwouts, Werner De Gersem, Geert De Kerf, Wilfried De Neve, Bie De Ost, Ana Maria Luiza Olteanu, Sylvie Rottey, Tom Vercauteren, Ingeborg Goethals, Fréderic Duprez
PURPOSE: To evaluate feasibility, disease control, survival, and toxicity after adaptive18 F-fluorodeoxyglucose (FDG) positron emisson tomography (PET) guided radiotherapy in patients with recurrent and second primary head and neck squamous cell carcinoma. METHODS: A prospective trial investigated the feasibility of adaptive intensity modulated radiotherapy (IMRT) ± concomitant cetuximab in 10 patients. The primary endpoint was achieving a 2-year survival free of grade >3 toxicity in ≥30% of patients...
March 19, 2018: Strahlentherapie und Onkologie: Organ der Deutschen Röntgengesellschaft ... [et Al]
Bin Cai, Olga L Green, Rojano Kashani, Vivian L Rodriguez, Sasa Mutic, Deshan Yang
The fast evolution of technology in radiotherapy (RT) enabled the realization of adaptive radiotherapy (ART). However, the new characteristics of ART pose unique challenges for efficiencies and effectiveness of quality assurance (QA) strategies. In this paper, we discuss the necessary QAs for ART and introduce a practical implementation. A previously published work on failure modes and effects analysis (FMEA) of ART is introduced first to explain the risks associated with ART sub-processes. After a brief discussion of QA challenges, we review the existing QA strategies and tools that might be suitable for each ART step...
March 14, 2018: Zeitschrift Für Medizinische Physik
Robin De Roover, Wouter Crijns, Kenneth Poels, Ronald Peeters, Cédric Draulans, Karin Haustermans, Tom Depuydt
PURPOSE: Liquid fiducial markers have shown to be a promising alternative to solid gold markers in terms of imaging artifact reduction, patient comfort and compatibility with different imaging modalities. This study aims to investigate the performance of the novel BioXmark® liquid marker for state-of-the-art multi-modal imaging used in prostate cancer (PCa) radiotherapy, encompassing kV CT/CBCT, multi-parametric MRI and kV X-ray imaging. In addition, automatic detection of the liquid markers in X-ray imaging for prostate motion monitoring during treatment was investigated...
March 14, 2018: Medical Physics
Yoshikazu Maeda, Yoshitaka Sato, Hiroki Minami, Yutaka Yasukawa, Kazutaka Yamamoto, Hiroyasu Tamamura, Satoshi Shibata, Sayuri Bou, Makoto Sasaki, Yuji Tameshige, Kyo Kume, Hiroshi Ooto, Shigeru Kasahara, Yasuhiro Shimizu, Yusuke Saga, Akira Omoya, Makoto Saitou
PURPOSE: To evaluate the effectiveness of CT image-guided proton radiotherapy for prostate cancer by analyzing the positioning uncertainty and assessing daily dose change due to anatomical variations. MATERIALS AND METHODS: Patients with prostate cancer were treated by opposed lateral proton beams based on a passive scattering method using an in-room CT image-guided system. The system employs a single couch for both CT scanning and beam delivery. The patient was positioned by matching the boundary between the prostate and the rectum's anterior region identified in the CT images to the corresponding boundary in the simulator images after bone matching...
March 12, 2018: Medical Physics
John P Sheppard, Carlito Lagman, Giyarpuram N Prashant, Yasmine Alkhalid, Thien Nguyen, Courtney Duong, Methma Udawatta, Bilwaj Gaonkar, Stephen E Tenn, Orin Bloch, Isaac Yang
OBJECTIVE: To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon) to those determined by Adaptive Hybrid Surgery (AHS) operative planning software in 7 vestibular schwannoma (VS) cases. METHODS: Four attending surgeons (3 neurosurgeons and 1 ear, nose, and throat surgeon) manually contoured planned residual tumors volumes for 7 consecutive VS patients. Next, the AHS software determined the ideal radiosurgical target volumes based on a specified radiotherapy plan...
March 9, 2018: World Neurosurgery
Vikas Gupta, Yibing Wang, Alejandra Méndez Romero, Andriy Myronenko, Petr Jordan, Calvin Maurer, Ben Heijmen, Mischa Hoogeman
PURPOSE: To validate a novel deformable image registration (DIR) method for online adaptation of planning organ-at-risk (OAR) delineations to match daily anatomy during hypo-fractionated RT of abdominal tumors. MATERIALS AND METHODS: For 20 liver cancer patients, planning OAR delineations were adapted to daily anatomy using the DIR on corresponding repeat CTs. The DIR's accuracy was evaluated for the entire cohort by comparing adapted and expert-drawn OAR delineations using geometric (Dice Similarity Coefficient (DSC), Modified Hausdorff Distance (MHD) and Mean Surface Error (MSE)) and dosimetric (Dmax and Dmean ) measures...
March 8, 2018: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
M Lazzeroni, J Uhrdin, S Carvalho, W van Elmpt, P Lambin, A Dasu, P Wersäll, I Toma-Dasu
PURPOSE: Early assessment of tumour response to treatment with repeated FDG-PET-CT imaging has potential for treatment adaptation but it is unclear what the optimal time window for this evaluation is. Previous studies indicate that changes in SUVmean and the effective radiosensitivity (αeff , accounting for uptake variations and accumulated dose until the second FDG-PET-CT scan) are predictive of 2-year overall survival (OS) when imaging is performed before radiotherapy and during the second week...
February 2018: Physica Medica: PM
Ryo Nishikawa, Kenji Yoshida, Yasuhiko Ebina, Mayumi Omoteda, Daisuke Miyawaki, Takeaki Ishihara, Yasuo Ejima, Hiroaki Akasaka, Hitoaki Satoh, Katsusuke Kyotani, Satoru Takahashi, Ryohei Sasaki
This study aimed to compare dosimetric parameters between non-optimized and optimized treatment planning (NOP and OP, respectively) of magnetic resonance imaging (MRI) -based intracavitary (IC) image-guided adaptive brachytherapy (IGABT) using the central shielding (CS) technique for cervical cancer. Fifty-three patients treated with external beam radiotherapy using CS and MRI-based IGABT with the IC approach alone were evaluated. The total high-risk clinical target volume (HR-CTV) D90 was aimed at >70 Gy equivalent dose in 2 Gy fractions (EQD2)...
March 6, 2018: Journal of Radiation Research
D Nashan, S Dengler
The spectrum of dermato-oncological emergencies is multifaceted. They are particularly observed in cases with malignant melanoma due to the large number of patients and prolonged survival rates that are associated with new therapies for advanced disease. Dermato-oncological patients present to the hospital with symptoms like nausea and emesis, unexpected neurological deficits, various gastrointestinal problems, and even acute abdomen, acute breathlessness, or hemoptysis. Furthermore, emergencies can be caused by hematological problems like anemia and leukopenia...
March 7, 2018: Der Hautarzt; Zeitschrift Für Dermatologie, Venerologie, und Verwandte Gebiete
Stéphane Supiot, Caroline Rousseau, Mélanie Dore, Catherine Cheze-Le-Rest, Christine Kandel-Aznar, Vincent Potiron, Stéphane Guerif, François Paris, Ludovic Ferrer, Loïc Campion, Philippe Meingan, Gregory Delpon, Mathieu Hatt, Dimitris Visvikis
Purpose: Hypoxia is a major factor in prostate cancer aggressiveness and radioresistance. Predicting which patients might be bad candidates for radiotherapy may help better personalize treatment decisions in intermediate-risk prostate cancer patients. We assessed spatial distribution of18 F-Misonidazole (FMISO) PET/CT uptake in the prostate prior to radiotherapy treatment. Materials and Methods: Intermediate-risk prostate cancer patients about to receive high-dose (>74 Gy) radiotherapy to the prostate without hormonal treatment were prospectively recruited between 9/2012 and 10/2014...
February 9, 2018: Oncotarget
Ali Ajdari, Archis Ghate, Minsun Kim
Recent theoretical research on spatiobiologically integrated 
 radiotherapy has focused on optimization models that adapt fluence-maps to the 
 evolution of tumor state, for example, cell densities, as observed in quantitative 
 functional images 
 acquired over the treatment course. We propose an optimization 
 model that adapts the length of the treatment course as well as the fluence-maps 
 to such imaged tumor state. Specifically, after observing the tumor cell 
 densities at the beginning of a session, the treatment planner solves a group of convex optimization problems to determine an optimal number of remaining treatment sessions, and a corresponding optimal fluence-map for each of these sessions...
March 7, 2018: Physics in Medicine and Biology
Adam Wang, Alexander Maslowski, Philippe Messmer, Mathias Lehmann, Adam Strzelecki, Elaine Yu, Pascal Paysan, Marcus Brehm, Peter Munro, Josh Star-Lack, Dieter Seghers
PURPOSE: To correct for scatter in kV cone-beam CT (CBCT) projection data on a clinical system using a new tool, Acuros® CTS, that estimates scatter images rapidly and accurately by deterministically solving the linear Boltzmann transport equation. METHODS: Phantom and patient CBCT scans were acquired on TrueBeam® radiotherapy machines. A first-pass reconstruction was used to create water and bone density maps of the imaged object, which was updated to include a more accurate representation of the patient couch...
March 6, 2018: Medical Physics
Abdelfettah Zidane, Adil Arsalane, Mohammed Lahkim, Issam Lalya, Abderrahim Ktaibi, Ismail Essadi
BACKGROUND: Radiotherapy associated with chemotherapy is a well-established treatment modality for locally advanced non-small cell lung cancers. Radiation-induced second malignancies, particularly radiation-induced sarcomas, are rare. Some authors reported a recent increase in the incidence of this rare complication, especially because of the improved prognosis and survival of patients after radiotherapy. Pathogenic mechanisms of radiation-induced sarcomas are poorly understood. However, diagnosis criteria are well established...
March 5, 2018: Journal of Medical Case Reports
Paul J Bröckelmann, Stephanie Sasse, Andreas Engert
With defined chemo- and radiotherapy and risk-adapted treatment, early-stage classical Hodgkin lymphoma (HL) has become curable in the majority of patients. A major current goal is hence to reduce treatment-related toxicity while maintaining long-term disease control. Patients with early-stage favorable disease, i.e. limited stage without risk factors (RFs), are frequently treated with two cycles of doxorubicin, bleomycin, vinblastine and dacarbazine (2xABVD) followed by 20Gy involved-field or -site radiotherapy (IF/IS-RT)...
March 2, 2018: Blood
Sean H Lim, Peter W M Johnson
The treatment of Hodgkin Lymphoma has evolved continuously since the introduction of extended-field radiotherapy in the 1960s to involved-field then involved-node radiotherapy, multi-agent chemotherapy, combined chemo-radiotherapy, risk-adapted and response-adapted modulation, and most recently, introduction of antibody-drug conjugates and immune checkpoint-blocking antibodies. These changes have translated into progressively increasing cure rates, so that 10-year survival figures now exceed 80%, compared to less than 50% 40 years ago...
March 2, 2018: Blood
Hoda Sharifi, Hong Zhang, Hassan Bagher Ebadian, Wei Lu, Munther I Ajlouni, Jian-Yue Jin, Feng-Ming Spring Kong, Indrin J Chetty, Hualiang Zhong
Tumor response to radiation treatment (RT) can be evaluated from changes in metabolic activity between two positron emission tomography (PET) images. Activity changes at individual voxels in pre-treatment PET images (PET1), however, cannot be derived until their associated PET-CT (CT1) images are appropriately registered to during-treatment PET-CT (CT2) images. This study aimed to investigate the feasibility of using deformable image registration (DIR) techniques to quantify radiation-induced metabolic changes on PET images...
February 26, 2018: Physics in Medicine and Biology
Lei Zhou, Xiaoying Zhang, Hui Li, Chao Niu, Dehai Yu, Guozi Yang, Xinyue Liang, Xue Wen, Min Li, Jiuwei Cui
Although low-dose radiation (LDR) possesses the two distinct functions of inducing hormesis and adaptive responses, which result in immune enhancement and tumor inhibition, its clinical applications have not yet been elucidated. The major obstacle that hinders the application of LDR in the clinical setting is that the mechanisms underlying induction of tumor inhibition are unclear, and the risks associated with LDR are still unknown. Thus, to overcome this obstacle and elucidate the mechanisms mediating the antitumor effects of LDR, in this study, we established an in vivo lung cancer model to investigate the participation of the immune system in LDR-induced tumor inhibition and validated the pivotal role of the immune system by impairing immunity with high-dose radiation (HDR) of 1 Gy...
February 25, 2018: Cancer Medicine
Roberto Berenguer, Victoria de la Vara, Veronica Lopez-Honrubia, Ana Teresa Nuñez, Miguel Rivera, Maria Victoria Villas, Sebastia Sabater
PURPOSE: To analyse the influence of the image registration method on the adaptive radiotherapy of an IMRT prostate treatment, and to compare the dose accumulation according to 3 different image registration methods with the planned dose. MATERIAL AND METHODS: The IMRT prostate patient was CT imaged 3 times throughout his treatment. The prostate, PTV, rectum and bladder were segmented on each CT. A Rigid, a deformable (DIR) B-spline and a DIR with landmarks registration algorithms were employed...
January 2018: Physica Medica: PM
Ian R Wisecarver, Gerhard S Mundinger, Michael S Tarakji, Hugo St Hilaire
Squamous cell carcinoma (SCC) of the head and neck affects a significant number of people around the world every year. Treatment generally entails surgical resection, radiotherapy, chemotherapy, or some combination of the three. Following resection, microsurgical reconstruction can provide definitive coverage, replace many tissue types simultaneously, and bring healthy tissue to irradiated wound beds. Microsurgical engineering, the manipulation and reorganization of native vascular tissue, can further augment the adaptability of free tissue transfer to complex, compromised wound beds...
January 2018: Plastic and Reconstructive Surgery. Global Open
Odelin Charron, Alex Lallement, Delphine Jarnet, Vincent Noblet, Jean-Baptiste Clavier, Philippe Meyer
Stereotactic treatments are today the reference techniques for the irradiation of brain metastases in radiotherapy. The dose per fraction is very high, and delivered in small volumes (diameter <1 cm). As part of these treatments, effective detection and precise segmentation of lesions are imperative. Many methods based on deep-learning approaches have been developed for the automatic segmentation of gliomas, but very little for that of brain metastases. We adapted an existing 3D convolutional neural network (DeepMedic) to detect and segment brain metastases on MRI...
February 9, 2018: Computers in Biology and Medicine
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