Browsing by Author "Ozyar, Enis"

Now showing 1 - 20 of 29

Carotid blowout syndrome after intensity-modulated radiation therapy: A case report
(MARMARA UNIV, FAC MEDICINE, 2017-01-01) Sahin, Bilgehan; Atalar, Banu; Yakupoglu, Abdullah; Ozyar, Enis
Carotid blowout syndrome (CBS) is a rarely seen complication of head-neck surgery and radiation therapy. It may present by massive ear bleeding or epistaxis with high morbidity and mortality rates. Success rate of endovascular therapy or emergency surgery is unfortunately low because of massive bleeding and weakened vessel architecture. Here, we present a 45-year-old male with nasopharyngeal carcinoma and treated with intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy. The patient was diagnosed with stage III (T3N2M0) carcinoma of the nasopharynx. Eight months after radiotherapy, he was admitted to hospital with the complaint of epistaxis. Right internal carotid angiography revealed a 4 mm pseudoaneurysm at the superior-anterior wall of the petrous and his bleeding was controlled by stenting in the same session. In this report we aimed to draw attention to this rare clinical situation that might enhance the chance of early diagnosis enabling less morbid treatment opportunities.
Clinical adoption patterns of 0.35 Tesla MR-guided radiation therapy in Europe and Asia
(BMC, 2022-01-01) Slotman, Berend J.; Clark, Mary Ann; Ozyar, Enis; Kim, Myungsoo; Itami, Jun; Tallet, Agnes; Debus, Juergen; Pfeffer, Raphael; Gentile, PierCarlo; Hama, Yukihiro; Andratschke, Nicolaus; Riou, Olivier; Camilleri, Philip; Belka, Claus; Quivrin, Magali; Kim, BoKyong; Pedersen, Anders; Felter, Mette van Overeem; Kim, Young Il; Kim, Jin Ho; Fuss, Martin; Valentini, Vincenzo
Background Magnetic resonance-guided radiotherapy (MRgRT) utilization is rapidly expanding, driven by advanced capabilities including better soft tissue imaging, continuous intrafraction target visualization, automatic triggered beam delivery, and the availability of on-table adaptive replanning. Our objective was to describe patterns of 0.35 Tesla (T)-MRgRT utilization in Europe and Asia among early adopters of this novel technology. Methods Anonymized administrative data from all 0.35T-MRgRT treatment systems in Europe and Asia were extracted for patients who completed treatment from 2015 to 2020. Detailed treatment information was analyzed for all MR-linear accelerators (linac) and -cobalt systems. Results From 2015 through the end of 2020, there were 5796 completed treatment courses delivered in 46,389 individual fractions. 23.5\% of fractions were adapted. Ultra-hypofractionated (UHfx) dose schedules (1-5 fractions) were delivered for 63.5\% of courses, with 57.8\% of UHfx fractions adapted on-table. The most commonly treated tumor types were prostate (23.5\%), liver (14.5\%), lung (12.3\%), pancreas (11.2\%), and breast (8.0\%), with increasing compound annual growth rates (CAGRs) in numbers of courses from 2015 through 2020 (pancreas: 157.1\%
Dealing with the gray zones in the management of gastric cancer: The consensus statement of the Istanbul Group
(AVES, 2019-01-01) Aytac, Erman; Aslan, Fatih; Cicek, Bahattin; Erdamar, Sibel; Gurses, Bengi; Guven, Koray; Falay, Okan; Karahasanoglu, Tayfun; Selcukbiricik, Fatih; Selek, Ugur; Atalar, Banu; Balik, Emre; Tozun, Nurdan; Rozanes, Izzet; Arican, Ali; Hamzaoglu, Ismail; Baca, Bilgi; Mandell, Nil Molinas; Saruc, Murat; Goksel, Suha; Demir, Gokhan; Agaoglu, Fulya; Yakicier, Cengiz; Ozbek, Ugur; Ozben, Volkan; Ozyar, Enis; Guner, Ahmet Levent; Er, Ozlem; Kaban, Kerim; Bolukbasi, Yasemin; Bugra, Dursun; Ahishali, Emel; Asian, Fatih; Boz-bas, Aysun; Hamzaoglu, Hulya; Karaman, Ahmet; Kucukmetin, Nurten Turkel; Vardareli, Eser Kutsal; Onder, Fatih Oguz; Sisman, Gurhan; Tiftikci, Arzu; Unal, Hakan Umit; Yapali, Suna; Acar, Sami; Agcaoglu, Orhan; Aghayeva, Afag; Akyuz, Ali; Atasoy, Deniz; Batik, Emre; Bayraktar, Ilknur Erenler; Bayram, Onur; Bilgic, Cagri; Bilgin, Ismail Ahmet; Can, Ugur; Dulgeroglu, Onur; Durukan, Ugur; Gencosmanoglu, Rasim; Gonenc, Murat; Gurbuz, Bulent; Kaya, Mesut; Omarov, Nail; Ozben, Volkan; Ozgur, Ilker; Ozoran, Emre; Sobutay, Erman; Uras, Cihan; Uymaz, Derya; Zenger, Serkan; Ozbek, Ugur; Yakicier, M. Cengiz; Afsar, Cigdem Usul; Bozkurt, Mustafa; Demir, Atakan; Er, Ozlem; Kanitez, Metin; Korkmaz, Taner; Mandel, Nil Molina; Mert, Askhan Guven; Ozer, Leyla; Sonmez, Ozlem; Tunali, Didem; Uluc, Basak Oyan; Yazar, Aziz; Yildiz, Ibrahim; Demirkurek, Cengiz; Guner, Ahmet Levent; Vardareli, Erkan; Armutlu, Aye; Baba, Fisun; Ersozlu, Ilker; Kapran, Yersu; Sahin, Davut; Abacioglu, Mehmet Ufuk; Bese, Nuran; Durankus, Nilufer Kilic; Gural, Zeynep; Ozyar, Enis; Sengoz, Meric; Sezen, Duygu; Caliskan, Can; Guven, Koray; Karaaslan, Ercan; Kizilkaya, Esref; Suleyman, Erdogan; Grp, Istanbul
The geographical location and differences in tumor biology significantly change the management of gastric cancer. The prevalence of gastric cancer ranks fifth and sixth among men and women, respectively, in Turkey. The international guidelines from the Eastern and Western countries fail to manage a considerable amount of inconclusive issues in the management of gastric cancer. The uncertainties lead to significant heterogeneities in clinical practice, lack of homogeneous data collection, and subsequently, diverse outcomes. The physicians who are professionally involved in the management of gastric cancer at two institutions in Istanbul, Turkey, organized a consensus meeting to address current problems and plan feasible, logical, measurable, and collective solutions in their clinical practice for this challenging disease. The evidence-based data and current guidelines were reviewed. The gray zones in the management of gastric cancer were determined in the first session of this consensus meeting. The second session was constructed to discuss, vote, and ratify the ultimate decisions. The identification of the T stage, the esophagogastric area, imaging algorithm for proper staging and follow-up, timing and patient selection for neoadjuvant treatment, and management of advanced and metastatic disease have been accepted as the major issues in the management of gastric cancer. The recommendations are presented with the percentage of supporting votes in the results section with related data.
Evaluation of response to stereotactic radiosurgery in patients with radioresistant brain metastases
(KOREAN SOC THERAPEUTIC RADIOLOGY \& ONCOLOGY, 2019-01-01) Sayan, Mutlay; Mustafayev, Teuta Zoto; Sahin, Bilgehan; Kefelioglu, Erva Seyma Sare; Wang, Shang-Jui; Kurup, Varsha; Balmuk, Aykut; Gungor, Gorkem; Ohri, Nisha; Weiner, Joseph; Ozyar, Enis; Atalar, Banu
Purpose: Renal cell carcinoma (RCC) and melanoma have been considered `radioresistant' due to the fact that they do not respond to conventionally fractionated radiation therapy. Stereotactic radiosurgery (SRS) provides high-dose radiation to a defined target volume and a limited number of studies have suggested the potential effectiveness of SRS in radioresistant histologies. We sought to determine the effectiveness of SRS for the treatment of patients with radioresistant brain metastases. Materials and Methods: We performed a retrospective review of our institutional database to identify patients with RCC or melanoma brain metastases treated with SRS. Treatment response were determined in accordance with the Response Evaluation Criteria in Solid Tumors. Results: We identified 53 radioresistant brain metastases (28\% RCC and 72\% melanoma) treated in 18 patients. The mean target volume and coverage was 6.2 +/- 9.5 mL and 95.5\% +/- 2.9\%, respectively. The mean prescription dose was 20 +/- 4.9 Gy. Forty lesions (75\%) demonstrated a complete/partial response and 13 lesions (24\%) with progressive/stable disease. Smaller target volume (p < 0.001), larger SRS dose (p < 0.001), and coverage (p = 0.008) were found to be positive predictors of complete response to SRS. Conclusion: SRS is an effective management option with up to 75\% response rate for radioresistant brain metastases. Tumor volume and radiation dose are predictors of response and can be used to guide the decision-making for patients with radioresistant brain metastases.
First 500 Fractions Delivered with a Magnetic Resonance-guided Radiotherapy System: Initial Experience
(CUREUS INC, 2019-01-01) Sahin, Bilgehan; Mustafayev, Teuta Zoto; Gungor, Gorkem; Aydin, Gokhan; Yapici, Bulent; Atalar, Banu; Ozyar, Enis
Objectives Improved soft-tissue visualization, afforded by magnetic resonance imaging integrated into a radiation therapy linear accelerator-based radiation delivery system (MR-linac) promises improved image-guidance. The availability of MR-imaging can facilitate on-table adaptive radiation planning and enable real-time intra-fraction imaging with beam gating without additional exposure to radiation. However, the novel use of magnetic resonance-guided radiation therapy (MRgRT) in the field of radiation oncology also potentially poses challenges for routine clinical implementation. Herein the early experience of a single institution, implementing the first MRgRT system in the country is reported. We aim to describe the workflow and to characterize the clinical utility and feasibility of routine use of an MR-linac system. Methods The ViewRay MRIdian MR-linac system consists of a split-magnet 0.35 T MR-imaging scanner with a double focused multi-leaf collimator (MLC) equipped 6MV linear accelerator. Unique to the system are the control console integrated on-table adaptive radiation therapy (oART) planning capabilities as well as automated beam gating based on real-time intra-fraction MR imaging. From the first day of clinical implementation, oART was performed according to physicians' discretion when medically indicated. All fractions were delivered under real-time imaging with soft tissue-based automated beam gating with individualized gating boundary settings. Patients actively assisted in breath-hold beam gating with the help of custom designed prismatic glasses allowing sight of a computer monitor mounted on the back wall just behind the MRI system bore. Patient demographics and treatment experience, indications for MRgRT including diagnosis and disease site, radiation dose prescribed and fractionation scheme, utilization of oART, respiratory gating settings, as well as duration of each treatment phase were analyzed. Results Between September 2018 and May 2019, 72 patients with 84 tumor sites were treated with MRgRT in 500 total fractions. Median patient age was 66 years (range: 28-83 years). Among 84 tumor sites, the most frequently treated regions were upper abdominal and pelvic (n = 36, 43\% and n = 29, 34\%, respectively). The most common diagnosis was prostate cancer, with 14 patients treated. In 69 patients (93.2\%) oART was used at least once during a treatment course. Twenty-nine targets (43.1\%) with significant breathing-related motion were treated in breath-hold with patient visual feedback. Median prescribed dose was 36.25 Gy (range: 24-70 Gy) in median five fractions (range: 3-28 fractions). A gating boundary of 3 mm around a gating region of interest (gROI) was most commonly used (range: 3-5 mm) with 95\% of the gROI (range: 93-97\%) required to be within the gating boundary for the beam to automatically engage. Mean total treatment time was 47 min (range: 21-125 min) and mean beam-on time was 16.7 min (range: 6-62 min). Conclusions MRgRT afforded by an MR-linac system has been successfully implemented into routine clinical use at our institution as the first system of its kind in Turkey. While the overall number of patients treated and fractions delivered is still limited, we have demonstrated the feasibility of both on-table adaptive radiation therapy as well as automated real-time beam gating on a daily basis in acceptable time schedules.
History of the Rare Cancer Network and past research
(PAGEPRESS PUBL, 2014-01-01) Mirimanoff, Rene-Olivier; Ozsahin, Mahmut; Thariat, Juliette; Ozyar, Enis; Schick, Ulrike; Pehlivan, Berrin; Krengli, Marco; Pellanda, Alessandra Franzetti; Vees, Hansjoerg; Cai, Ling; Scandolaro, Luciano; Belkacemi, Yazid; Villa, Salvador; Igdem, Sefik; Lutsyk, Myroslav; Miller, Robert C.
Approximately, twenty years ago, the Rare Cancer Network (RCN) was formed in Lausanne, Switzerland, to support the study of rare malignancies. The RCN has grown over the years and now includes 130 investigators from twenty-four nations on six continents. The network held its first international symposium in Nice, France, on March 21-22, 2014. The proceedings of that meeting are presented and contains the abstracts of fourteen oral presentations made at the meeting of prior RCN studies. From 1993 to 2014, 74 RCN studies have been initiated, of which 54 were completed, 10 are in progress or under analysis, and 9 were stopped due to poor accrual. Forty-four peer reviewed publications have been written on behalf of the RCN.
Improvement of conformal arc plans by using deformable margin delineation method for stereotactic lung radiotherapy
(WILEY, 2018-01-01) Gungor, Gorkem; Demir, Melek; Aydin, Gokhan; Yapici, Bulent; Atalar, Banu; Ozyar, Enis
Purpose: Stereotactic body radiotherapy (SBRT) is an established treatment technique in the management of medically inoperable early stage non-small cell lung cancer (NSCLC). Different techniques such as volumetric modulated arc (VMAT) and three-dimensional conformal arc (DCA) can be used in SBRT. Previously, it has been shown that VMAT is superior to DCA technique in terms of plan evaluation parameters. However, DCA technique has several advantages such as ease of use and considerable shortening of the treatment time. DCA technique usually results in worse conformity which is not possible to ameliorate by inverse optimization. In this study, we aimed to analyze whether a simple method-deformable margin delineation (DMD)-improves the quality of the DCA technique, reaching similar results to VMAT in terms of plan evaluation parameters. Methods: Twenty stage I-II (T1-2, N0, M0) NSCLC patients were included in this retrospective dosimetric study. Noncoplanar VMAT and conventional DCA plans were generated using 6 MV and 10 MV with flattening filter free (FFF) photon energies. The DCA plan with 6FFF was calculated and 95\% of the PTV was covered by the prescription isodose line. Hot dose regions (receiving dose over 100\% of prescription dose) outside PTV and cold dose regions (receiving dose under 100\% of prescription dose) inside PTV were identified. A new PTV (PTV-DMD) was delineated by deforming PTV margin with respect to hot and cold spot regions obtained from conventional DCA plans. Dynamic multileaf collimators (MLC) were set to PTV-DMD beam eye view (BEV) positions and the new DCA plans (DCA-DMD) with 6FFF were generated. Three-dimensional (3D) dose calculations were computed for PTV-DMD volume. However, the prescription isodose was specified and normalized to cover 95\% volume of original PTV. Several conformity indices and lung doses were compared for different treatment techniques. Results: DCA-DMD method significantly achieved a superior conformity index (CI), conformity number (CIPaddick), gradient index (R-50\%), isodose at 2 cm (D-2 (cm)) and external index (CD) with respect to VMAT and conventional DCA plans (P < 0.05 for all comparisons). CI ranged between 1.00-1.07 (Mean: 1.02)
Intensity modulated radiotherapy (IMRT) in bilateral retinoblastoma
(ASSOC RADIOLOGY \& ONCOLOGY, 2010-01-01) Atalar, Banu; Ozyar, Enis; Gunduz, Kaan; Gungor, Gorkem
Background. External beam radiotherapy (EBRT) for retinoblastoma has traditionally been done with conventional radiotherapy techniques which resulted high doses to the surrounding normal tissues. Case report. A 20 month-old girl with group D bilateral retinoblastoma underwent intensity modulated radiotherapy (IMRT) to both eyes after failing chemoreduction and focal therapies including cryotherapy and transpupillary thermotherapy. In this report, we discuss the use of IMRT as a method for reducing doses to adjacent normal tissues while delivering therapeutic doses to the tumour tissues compared with 3-dimensional conformal radiotherapy (3DCRT). At one year follow-up, the patient remained free of any obvious radiation complications. Conclusions. Image guided IMRT provides better dose distribution than 3DCRT in retinoblastoma eyes, delivering the therapeutic dose to the tumours and minimizing adjacent tissue damage.
International guideline for the delineation of the clinical target volumes (CTV) for nasopharyngeal carcinoma
(ELSEVIER IRELAND LTD, 2018-01-01) Lee, Anne W.; Ng, Wai Tong; Pan, Jian Ji; Poh, Sharon S.; Ahn, Yong Chan; AlHussain, Hussain; Corry, June; Grau, Cai; Gregoire, Vincent; Harrington, Kevin J.; Hu, Chao Su; Kwong, Dora L.; Langendijk, Johannes A.; Le, Quynh Thu; Lee, Nancy Y.; Lin, Jin Ching; Lu, Tai Xiang; Mendenhall, William M.; O'Sullivan, Brian; Ozyar, Enis; Peters, Lester J.; Rosenthal, David I.; Soong, Yoke Lim; Tao, Yungan; Yom, Sue S.; Wee, Joseph T.
Purpose: Target delineation in nasopharyngeal carcinoma (NPC) often proves challenging because of the notoriously narrow therapeutic margin. High doses are needed to achieve optimal levels of tumour control, and dosimetric inadequacy remains one of the most important independent factors affecting treatment outcome. Method: A review of the available literature addressing the natural behaviour of NPC and correlation between clinical and pathological aspects of the disease was conducted. Existing international guidelines as well as published protocols specified by clinical trials on contouring of clinical target volumes (CTV) were compared. This information was then summarized into a preliminary draft guideline which was then circulated to international experts in the field for exchange of opinions and subsequent voting on areas with the greatest controversies. Results: Common areas of uncertainty and variation in practices among experts experienced in radiation therapy for NPC were elucidated. Iterative revisions were made based on extensive discussion and final voting on controversial areas by the expert panel, to formulate the recommendations on contouring of CTV based on optimal geometric expansion and anatomical editing for those structures with substantial risk of microscopic infiltration. Conclusion: Through this comprehensive review of available evidence and best practices at major institutions, as well as interactive exchange of vast experience by international experts, this set of consensus guidelines has been developed to provide a practical reference for appropriate contouring to ensure optimal target coverage. However, the final decision on the treatment volumes should be based on full consideration of individual patients' factors and facilities of an individual centre (including the quality of imaging methods and the precision of treatment delivery). (C) 2017 Elsevier B.V. All rights reserved.
International Guideline on Dose Prioritization and Acceptance Criteria in Radiation Therapy Planning for Nasopharyngeal Carcinoma
(ELSEVIER SCIENCE INC, 2019-01-01) Lee, Anne W.; Ng, Wai Tong; Pan, Jian Ji; Chiang, Chi-Leung; Poh, Sharon S.; Choi, Horace C.; Ahn, Yong Chan; AlHussain, Hussain; Corry, June; Grau, Cai; Gregoire, Vincent; Harrington, Kevin J.; Hu, Chao Su; Kwong, Dora L.; Langendijk, Johannes A.; Le, Quynh Thu; Lee, Nancy Y.; Lin, Jin Ching; Lu, Tai Xiang; Mendenhall, William M.; O'Sullivan, Brian; Ozyar, Enis; Peters, Lester J.; Rosenthal, David I.; Sanguineti, Giuseppe; Soong, Yoke Lim; Tao, Yungan; Yom, Sue S.; Wee, Joseph T.
Purpose: The treatment of nasopharyngeal carcinoma requires high radiation doses. The balance of the risks of local recurrence owing to inadequate tumor coverage versus the potential damage to the adjacent organs at risk (OARs) is of critical importance. With advancements in technology, high target conformality is possible. Nonetheless, to achieve the best possible dose distribution, optimal setting of dose targets and dose prioritization for tumor volumes and various OARs is fundamental. Radiation doses should always be guided by the As Low As Reasonably Practicable principle. There are marked variations in practice. This study aimed to develop a guideline to serve as a global practical reference. Methods and Materials: A literature search on dose tolerances and normal-tissue complications after treatment for nasopharyngeal carcinoma was conducted. In addition, published guidelines and protocols on dose prioritization and constraints were reviewed. A text document and preliminary set of variants was circulated to a panel of international experts with publications or extensive experience in the field. An anonymized voting process was conducted to rank the proposed variants. A summary of the initial voting and different opinions expressed by members were then recirculated to the whole panel for review and reconsideration. Based on the comments of the panel, a refined second proposal was recirculated to the same panel. The current guideline was based on majority voting after repeated iteration for final agreement. Results: Variation in opinion among international experts was repeatedly iterated to develop a guideline describing appropriate dose prioritization and constraints. The percentage of final agreement on the recommended parameters and alternative views is shown. The rationale for the recommendations and the limitations of current evidence are discussed. Conclusions: Through this comprehensive review of available evidence and interactive exchange of vast experience by international experts, a guideline was developed to provide a practical reference for setting dose prioritization and acceptance criteria for tumor volumes and OARs. The final decision on the treatment prescription should be based on the individual clinical situation and the patient's acceptance of optimal balance of risk. (C) 2019 Elsevier Inc. All rights reserved.
International Recommendations on Reirradiation by Intensity Modulated Radiation Therapy for Locally Recurrent Nasopharyngeal Carcinoma
(ELSEVIER SCIENCE INC, 2021-01-01) Ng, Wai Tong; Soong, Yoke Lim; Ahn, Yong Chan; AlHussain, Hussain; Choi, Horace C. W.; Corry, June; Gregoire, Vincent; Harrington, Kevin J.; Hu, Chao Su; Jensen, Kenneth; Kwong, Dora L.; Langendijk, Johannes A.; Le, Quynh Thu; Lee, Nancy Y.; Lin, Jin Ching; Lu, Tai Xiang; Mendenhall, William M.; O'Sullivan, Brian; Ozyar, Enis; Pan, Jian Ji; Peters, Lester J.; Poh, Sharon S.; Rosenthal, David I.; Sanguineti, Giuseppe; Tao, Yungan; Wee, Joseph T.; Yom, Sue S.; Chua, Melvin L. K.; Lee, Anne W. M.
Purpose: Reirradiation for locally recurrent nasopharyngeal carcinoma (NPC) is challenging because prior radiation dose delivered in the first course is often close to the tolerance limit of surrounding normal structures. A delicate balance between achieving local salvage and minimizing treatment toxicities is needed. However, high-level evidence is lacking because available reports are mostly retrospective studies on small series of patients. Pragmatic consensus guidelines, based on an extensive literature search and the pooling of opinions by leading specialists, will provide a useful reference to assist decision-making for these difficult decisions. Methods and Materials: A thorough review of available literature on recurrent NPC was conducted. A set of questions and preliminary draft guideline was circulated to a panel of international specialists with extensive experience in this field for voting on controversial areas and comments. A refined second proposal, based on a summary of the initial voting and different opinions expressed, was recirculated to the whole panel for review and reconsideration. The current guideline was based on majority voting after repeated iteration for final agreement. Results: The initial round of questions showed variations in clinical practice even among the specialists, reflecting the lack of high-quality supporting data and the difficulties in formulating clinical decisions. Through exchange of comments and iterative revisions, recommendations with high-to-moderate agreement were formulated on general treatment strategies and details of reirradiation (including patient selection, targets contouring, dose prescription, and constraints). Conclusion: This paper provides useful reference on radical salvage treatment strategies for recurrent NPC and optimization of reirradiation through review of published evidence and consensus building. However, the final decision by the attending clinician must include full consideration of an individual patient's condition, understanding of the delicate balance between risk and benefits, and acceptance of risk of complications. (C) 2021 Elsevier Inc. All rights reserved.
Linguistic Validation of the Turkish Version of the MD Anderson Symptom Inventory - Head and Neck Cancer Module
(GALENOS PUBL HOUSE, 2016-01-01) Gunn, G. Brandon; Atalar, Banu; Mendoza, Tito R.; Cleeland, Charles S.; Selek, Ugur; Ozyar, Enis; Rosenthal, David I.
Background: The use of patient symptom reports with frequent symptom assessment may be preferred over the more commonly used health-related quality of life questionnaires. Aims: We sought to linguistically validate the Turkish version of the M.D. Anderson Symptom Inventory-Head and Neck module (MDASI-HN) patient reported outcome questionnaire. Study Design: Validation study. Methods: Following standard forward and backward translation of the original and previously validated English MDASI-HN into a Turkish version (T-MDASI-HN), it was administered to patients with head and neck cancer able to read and understand Turkish. Patients were then cognitively debriefed to evaluate their understanding and comprehension of the T-MDASI-HN. Individual and group responses are presented using descriptive statistics. Results: Twenty-six participants with head and neck cancer completed the T-MDASI-HN and accompanying cognitive debriefing. Overall, 97 percent of the individual TMDASI-HN items were completed. Average recorded time to complete the 28 item TMDASI-HN questionnaire was 5.4 minutes (range 2-10). Average overall ease of completion, understandability, and acceptability were favorably rated at 1.0, 1.1, and 0.2, respectively, on scales from 0 to 10. Only 5 of the 26 of participants reported trouble completing any single questionnaire items, namely the ``difficulty remembering{''} item for 3 individuals. Conclusion: The T-MDASI-HN is linguistically valid with ease of completion, relevance, comprehensibility, and applicability and it can be a useful clinical and research tool.
Long-term toxicity and survival outcomes after stereotactic ablative radiotherapy for patients with centrally located thoracic tumors
(WALTER DE GRUYTER GMBH, 2020-01-01) Atalar, Banu; Mustafayev, Teuta Zoto; Sio, Terence T.; Sahin, Bilgehan; Gungor, Gorkem; Aydin, Gokhan; Yapici, Bulent; Ozyar, Enis
Background. Stereotactic ablative radiotherapy (SABR) is effective for thoracic cancer and metastases
Magnetic resonance image-guided adaptive stereotactic body radiotherapy for prostate cancer: preliminary results of outcome and toxicity
(BRITISH INST RADIOLOGY, 2021-01-01) Ugurluer, Gamze; Atalar, Banu; Mustafayev, Teuta Zoto; Gungor, Gorkem; Aydin, Gokhan; Sengoz, Meric; Abacioglu, Ufuk; Tuna, Mustafa Bilal; Kural, Ali Riza; Ozyar, Enis
Objective: Using moderate or ultra-hypofractionation, which is also known as stereotactic body radiotherapy (SBRT) for treatment of localized prostate cancer patients has been increased. We present our preliminary results on the clinical utilization of MRI-guided adaptive radiotherapy (MRgRT) for prostate cancer patients with the workflow, dosimetric parameters, toxicities and prostate-specific antigen (PSA) response. Methods: 50 prostate cancer patients treated with ultrahypofractionation were included in the study. Treatment was performed with intensity-modulated radiation therapy (step and shoot) technique and daily plan adaptation using MRgRT. The SBRT consisted of 36.25 Gy in 5 fractions with a 7.25 Gy fraction size. The time for workflow steps was documented. Patients were followed for the acute and late toxicities and PSA response. Results: The median follow-up for our cohort was 10 months (range between 3 and 29 months). The median age was 73.5 years (range between 50 and 84 years). MRgRT was well tolerated by all patients. Acute genitourinary (GU) toxicity rate of Grade 1 and Grade 2 was 28 and 36\%, respectively. Only 6\% of patients had acute Grade 1 gastrointestinal (GI) toxicity and there was no Grade 2G1 toxicity. To date, late Grade 1 GU toxicity was experienced by 24\% of patients, 2\% of patients experienced Grade 2 GU toxicity and 6\% of patients reported Grade 2 GI toxicity. Due to the short follow-up, PSA nadir has not been reached yet in our cohort. Conclusion: In conclusion, MRgRT represents a new method for delivering SBRT with markerless soft tissue visualization, online adaptive planning and real-time tracking. Our study suggests that ultra-hypofractionation has an acceptable acute and very low late toxicity profile. Advances in knowledge: MRgRT represents a new markerless method for delivering SBRT for localized prostate cancer providing online adaptive planning and real-time tracking and acute and late toxicity profile is acceptable.
Magnetic Resonance Image-Guided Hypofractionated Ablative Radiation Therapy for Hepatocellular Carcinoma With Tumor Thrombus Extending to the Right Atrium
(CUREUS INC, 2022-01-01) Dincer, Neris; Ugurluer, Gamze; Mustafayev, Teuta Zoto; Gungor, Gorkem; Atalar, Banu; Guven, Koray; Ozyar, Enis
Hepatocellular carcinoma (HCC) presenting with tumor thrombus and inferior vena cave (IVC)/right atrium (RA) infringement point to an advanced-stage disease that is deemed inoperable. Stereotactic body radiotherapy is an emerging treatment option for this group of patients with promising outcomes in recent studies that are comparable to conventional treatment methods, namely, transarterial chemoembolization and transarterial radioembolization. Here, we report a case of HCC with RA extension through the IVC. The patient was referred to our clinic for treatment options, and he was found suitable for magnetic resonance imaging-guided radiotherapy (MRgRT). We treated the patient with MRgRT in five fractions to a total dose of 40 Gray. The tumor was tracked during the treatment sessions, and adaptive treatment planning was performed before each fraction. The patient tolerated the treatment well with no acute grade 3-4 toxicities. The last follow-up showed that the patient had a complete biochemical response and is now a candidate for an orthotopic liver transplant. To our knowledge, this report is the first to document the MRgRT treatment of an HCC with TT and RA extension. MRgRT is safe and feasible for this patient group and can be an effective bridging therapy for liver transplants.
Magnetic Resonance Imaging-Guided Online Adaptive Lattice Stereotactic Body Radiotherapy in Voluminous Liver Metastasis: Two Case Reports
(CUREUS INC, 2022-01-01) Dincer, Neris; Ugurluer, Gamze; Korkmaz, Latif; Serkizyan, Anatolia; Atalar, Banu; Gungor, Gorkem; Ozyar, Enis
Lattice Radiotherapy (LRT) is a technique in which heterogeneous doses are delivered to the target so large tumors can have optimal doses of radiation without compromising healthy tissue sparing. lb date, case reports and case series documented its application for bulky tumors mainly in the pelvic region. LRT not only provides dosimetric advantages but also promotes tumor control by triggering some radiobiological and immunological pathways. We report two cases of giant liver metastases for whom other treatment options were not suitable. We treated both patients with Magnetic Resonance Image-Guided Radiotherapy (MRgRT) with online adaptive LRT (OALRT) technique. Adaptive plans were generated before each fraction. Tumors were observed to have regressed interfractionally so the location and number of spheres were adapted to tumor size and daily anatomy of the surrounding organs at risk (OAR). Both patients had good treatment compliance without any Grade 3+ side effects. They are both under follow-up and report improvement. By reporting the first application of OALRT by using MRgRT in liver metastases, we show that MRgRT is a promising modality for LRT technique with better target and OAR visualization as well as online adaptive planning before each fraction according to the daily anatomy of the patient.
Magnetic Resonance Imaging-Guided Radiation Therapy for Early-Stage Gastric Mucosa-Associated Lymphoid Tissue Lymphoma
(CUREUS INC, 2022-01-01) Dincer, Neris; Ugurluer, Gamze; Gungor, Gorkem; Mustafayev, Teuta Zoto; Atalar, Banu; Ozyar, Enis
Lymphoid neoplasia derived from mucosa-associated lymphoid tissue (MALT
Management of symptomatic radiation necrosis after stereotactic radiosurgery and clinical factors for treatment response
(KOREAN SOC THERAPEUTIC RADIOLOGY \& ONCOLOGY, 2020-01-01) Sayan, Mutlay; Mustafayev, Teuta Zoto; Balmuk, Aykut; Mamidanna, Swati; Kefelioglu, Erva Seyma Sare; Gungor, Gorkem; Chundury, Anupama; Ohri, Nisha; Karaarslan, Ercan; Ozyar, Enis; Atalar, Banu
Purpose: Approximately 10\% of patients who received brain stereotactic radiosurgery (SRS) develop symptomatic radiation necrosis (RN). We sought to determine the effectiveness of treatment options for symptomatic RN, based on patient-reported outcomes. Materials and Methods: We conducted a retrospective review of 217 patients with 414 brain metastases treated with SRS from 2009 to 2018 at our institution. Symptomatic RN was determined by appearance on serial magnetic resonance images (MRIs), MR spectroscopy, requirement of therapy, and development of new neurological complaints without evidence of disease progression. Therapeutic interventions for symptomatic RN included corticosteroids, bevacizumab and/or surgical resection. Patient-reported therapeutic outcomes were graded as complete response (CR), partial response (PR), and no response. Results: Twenty-six patients experienced symptomatic RN after treatment of 50 separate lesions. The mean prescription dose was 22 Gy (range, 15 to 30 Gy) in 1 to 5 fractions (median, 1 fraction). Of the 12 patients managed with corticosteroids, 6 patients (50\%) reported CR and 4 patients (33\%) PR. Of the 6 patients managed with bevacizumab, 3 patients (50\%) reported CR and 1 patient (18\%) PR. Of the 8 patients treated with surgical resection, all reported CR (100\%). Other than surgical resection, age >= 54 years (median, 54 years
Multi-Institutional Outcomes of Stereotactic Magnetic Resonance Image Guided Adaptive Radiation Therapy With a Median Biologically Effective Dose of 100 Gy(10) for Non-bone Oligometastases
(ELSEVIER INC, 2022-01-01) Kutuk, Tugce; Herrera, Robert; Mustafayev, Teuta Z.; Gungor, Gorkem; Ugurluer, Gamze; Atalar, Banu; Kotecha, Rupesh; Hall, Matthew D.; Rubens, Muni; Mittauer, Kathryn E.; Contreras, Jessika A.; McCulloch, James; Kalman, Noah S.; Alvarez, Diane; Romaguera, Tino; Gutierrez, Alonso N.; Garcia, Jacklyn; Kaiser, Adeel; Mehta, Minesh P.; Ozyar, Enis; Chuong, Michael D.
Purpose: Randomized data show a survival benefit of stereotactic ablative body radiation therapy in selected patients with oligometastases (OM). Stereotactic magnetic resonance guided adaptive radiation therapy (SMART) may facilitate the delivery of ablative dose for OM lesions, especially those adjacent to historically dose-limiting organs at risk, where conventional approaches preclude ablative dosing. Methods and Materials: The RS Search Registry was queried for OM patients (1-5 metastatic lesions) treated with SMART. Freedom from local progression (FFLP), freedom from distant progression (FFDP), progression-free survival (PFS), and overall survival (LS) were estimated using the Kaplan-Meier method. FFLP was evaluated using RECIST 1.1 criteria. Toxicity was evaluated using Common Terminology Criteria for Adverse Events version 4 criteria. Results: Ninety-six patients with 108 OM lesions were treated on a 0.35 T MR Linac at 2 institutions between 2018 and 2020. SMART was delivered to mostly abdominal or pelvic lymph nodes (48.1\%), lung (18.5\%), liver and intrahepatic bile ducts (16.7\%), and adrenal gland (11.1\%). The median prescribed radiation therapy dose was 48.5 Gy (range, 30-60 Gy) in 5 fractions (range, 3-15). The median biologically effective dose corrected using an alpha/beta value of 10 was 100 Gy10 (range, 48-180). No acute or late grade 3+ toxicities were observed with median 10 months (range, 3-25) follow-up. Estimated 1-year FFLP, FFDP, PFS, and OS were 92.3\%, 41.1\%, 39.3\%, and 89.6\%, respectively. Median FFDP and PFS were 8.9 months (95\% confidence interval, 5.2-12.6 months) and 7.6 months (95\% confidence interval, 4.5-10.6 months), respectively. Conclusions: To our knowledge, this represents the largest analysis of SMART using ablative dosing for non-bone OM. A median prescribed biologically effective dose of 100 Gy10 resulted in excellent early FFLP and no significant toxicity, likely facilitated by continuous intrafraction MR visualization, breath hold delivery, and online adaptive replanning. Additional prospective evaluation of dose-escalated SMART for OM is warranted. (C) 2022 The Author(s). Published by Elsevier Inc. on behalf of American Society for Radiation Oncology.
Multichannel Film Dosimetry for Quality Assurance of Intensity Modulated Radiotherapy Treatment Plans Under 0.35 T Magnetic Field
(CUREUS INC, 2020-01-01) Gungor, Gorkem; Korkmaz, Latif; Kayalilar, Namik; Aydin, Gokhan; Yapici, Bulent; Mustafayev, Teuta Zoto; Atalar, Banu; Ozyar, Enis
Purpose To evaluate the intensity modulated radiotherapy (IMRT) quality assurance (OA) results of the multichannel film dosimetry analysis with single scan method by using Gafchromic (TM) EBT3 (Ashland Inc., Covington, KY, USA) film under 0.35 T magnetic field. Methods Between September 2018 and June 2019, 70 patients were treated with ViewRay MRldian (R) (ViewRay Inc., Mountain View, CA) linear accelerator (Linac). Film dosimetry OA plans were generated for all IMRT treatments. Multichannel film dosimetry for red, green and blue (RGB) channels were compared with treatment planning system (TPS) dose maps by gamma evaluation analysis. Results The mean gamma passing rates of RGB channels are 97.3\% +/- 2.26\%, 96.0\% +/- 3.27\% and 96.2\% +/- 3.14\% for gamma evaluation with 2\% DD/2 mm distance to agreement (DTA), respectively. Moreover, the mean gamma passing rates of RGB channels are 99.7\% +/- 0.41\%, 99.6\% +/- 0.59\% and 99.5\% +/- 0.67\% for gamma evaluation with 3\% DD/3 mm DTA, respectively. Conclusion The patient specific QA using Gafchromic (TM) EBT3 film with multichannel film dosimetry seems to he a suitable tool to implement for MR-guided IMRT treatments under 0.35 T magnetic field. Multichannel film dosimetry with Gafchromic (TM) EBT3 is a consistent QA tool for gamma evaluation of the treatment plans even with 2\% DD/2 mm DTA under 0.35 T magnetic field presence.