Reappraisal of Target Definition for Sacrococcygeal Chordoma: Comparative Assessment with Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) Volume 55- Issue 1

Murat Beyzadeoglu*, Selcuk Demiral, Ferrat Dincoglan and Omer Sager

• Department of Radiation Oncology, University of Health Sciences, Gulhane Medical Faculty, Turkey

Received: February 11, 2024; Published: February 19, 2024

*Corresponding author: Murat Beyzadeoglu, University of Health Sciences, Gulhane Medical Faculty, Department of Radiation Oncology, Gn. Tevfik Saglam Cad. 06018, Etlik, Kecioren, Ankara, Turkey

DOI: 10.26717/BJSTR.2024.55.008659

Abstract PDF

Objective: Chordomas account for a relatively small proportion of intracranial and primary bone tumors. However, they may cause local bone destruction with a typically aggressive disease course. Chordomas arise from embryonic remnants of the primitive notochord. Common localizations for chordoma include the spheno occipital region, sacrococcygeal region, and vertebral bodies. While distant metastasis is typically rare, chordomas may cause mass effect on the brainstem, cranial nerves and the spinal cord. Also, palpable mass may be a presentation for sacrococcygeal chordomas. While surgery remains to play a major role for successful management of sacrococcygeal chordomas, irradiation may serve as a complementary or alternative therapeutic strategy in certain circumstances. In the current study, we aimed at assessing target definition for sacrococcygeal chordomas with comparative evaluation of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI).

Materials and Methods: Primary objective of the current study was focused on target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI. All included patients were referred for RT at Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences for sacrococcygeal chordoma. We have performed a comparative analysis of target definition by CT simulation images for radiation treatment planning and with MRI.

Results: As the main result of this study, we have found that CT and MRI defined target definition resulted in differences.

Conclusion: In this study, we have found that CT and MRI defined target definition resulted in differences. Thus, fusion of CT and MRI has been utilized for ground truth target volume determination. Our results may have implications for implementation of multimodality imaging for target definition of sacrococcygeal chordomas despite the need for further supporting evidence.

Keywords: Sacrococcygeal Chordoma; Radiation Therapy (RT); Target Definition; Computed Tomography (CT); Magnetic Resonance Imaging (MRI)

Abbreviations: CT: Computed Tomography; MRI: Magnetic Resonance Imaging; EBRT: External Beam Radiation Therapy; IMRT: Intensity Modulated Radiation Therapy; ART: Adaptive Radiation Therapy; AAPM: American Association of Physicists in Medicine; ICRU: International Commission on Radiation Units and Measurements; IGRT: Image Guided Radiotherapy

Chordomas account for a relatively small proportion of intracranial and primary bone tumors. However, they may cause local bone destruction with a typically aggressive disease course. Chordomas arise from embryonic remnants of the primitive notochord. Common localizations for chordoma include the sphenooccipital region, sacrococcygeal region, and vertebral bodies. While distant metastasis is typically rare, chordomas may cause mass effect on the brainstem, cranial nerves, and the spinal cord. Also, palpable mass may be a presentation for sacrococcygeal chordomas. Microscopically, physaliphorous cells can be observed [1,2]. Sacrococcygeal chordomas may extend to the sacrum and may manifest as painful swelling within the sacrococcygeal region. Typical findings on Computed Tomography (CT) include an expansile lesion accompanied by peripheral calcification. Magnetic Resonance Imaging (MRI) may serve as an excellent imaging tool for assessment of osseous extent and soft tissue involvement. Both surgery and irradiation may be utilized for management of chordomas [3-11]. Irradiation may be used as an adjuvant or alternative therapeutic approach. External Beam Radiation Therapy (EBRT), particule therapy, and Stereotactic RT techniques may be utilized for effective management. While using higher doses for irradiation may contribute to improved local control outcomes, toxicity profile of radiation delivery should also be taken into account to maintain patient’s quality of life.

Several advances have taken place in technology in the millennium era. Molecular imaging methods, Image Guided RT (IGRT), automatic segmentation techniques, Intensity Modulated RT (IMRT), stereotactic RT, and Adaptive RT (ART) have been introduced for optimal radiotherapeutic management of patients [12-49]. Admittedly, improved treatment outcomes may solely be achieved through close collaboration among related disciplines for cancer management. Tumor boards may significantly contribute to bringing together surgical oncologists, radiation oncologists, medical oncologists, imaging and other relevant specialists to discuss about patient, tumor, and treatment characteristics. While surgery remains to play a major role for successful management of sacrococcygeal chordomas, irradiation may serve as a complementary or alternative therapeutic strategy in certain circumstances. In the current study, we aimed at assessing target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI.

At our Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences, we have long been treating a high patient population from several places from Turkey and abroad. Within this context, several benign and malignant tumors have been irradiated at our tertiary cancer center for decades. The primary objective of the current study was focused on target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI. All included patients were referred for RT at Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences for sacrococcygeal chordoma. We have performed a comparative analysis of target definition by CT simulation images for radiation treatment planning and with MRI. CT simulations of the patients were performed at CT-simulator (GE Lightspeed RT, GE Healthcare, Chalfont St. Giles, UK) available at our institution. Also, MRI of patients have been acquired and used for comparative assessment. A Linear Accelerator (LINAC) with the capability of contemporary IGRT techniques has been utilized for irradiation. After rigid patient immobilization, planning CT images have been acquired at CT simulator for radiation treatment planning. Thereafter, acquired RT planning images have been transferred to the contouring workstation via the network. Treatment volumes and critical organs have been defined on these images and structure sets have been generated. Also, target definition has also been performed on MRI for comparison. All patients have been treated by using state of the art RT techniques at the Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences.

This original research article has been designated for reappraisal of target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI. Irradiation procedures have been carried out at our Radiation Oncology Department of Gulhane Medical Faculty at University of Health Sciences, Ankara. Prior to treatment, all included patients have been individually evaluated by a multidisciplinary team of experts from surgical oncology and radiation oncology. We considered the reports by American Association of Physicists in Medicine (AAPM) and International Commission on Radiation Units and Measurements (ICRU) for accurate radiation treatment planning. Radiation physicists have generated radiation treatment plans by taking into account the relevant normal tissue dose limitations through meticulous consideration of contemporary guidelines and clinical experience. Tissue heterogeneity, electron density, CT number and HU values in CT images have also been considered by radiation physicists for precise radiation treatment planning. Main endpoint of radiation treatment planning has been to achieve optimal target coverage without violation of normal tissue dose constraints. Image Guided Radiotherapy (IGRT) techniques including kilovoltage cone beam CT and electronic digital portal imaging have been used, and radiation treatment was performed by Synergy (Elekta, UK) LINAC. As the main result of this study, we have found that CT and MRI defined target definition resulted in differences. Thus, fusion of CT and MRI has been utilized for ground truth target volume determination.

Chordomas comprise a relatively smaller proportion of intracranial and primary bone tumors. Nevertheless, they may cause local bone destruction with a typically aggressive disease course. Chordomas originate from embryonic remnants of the primitive notochord. Common localizations for chordoma include the sphenooccipital region, sacrococcygeal region, and vertebral bodies. While distant metastasis is typically rare, chordomas may cause mass effects on the brainstem, cranial nerves, and the spinal cord. Also, palpable mass may be a presentation for sacrococcygeal chordomas. Microscopically, physaliphorous cells can be observed [1,2]. Sacrococcygeal chordomas may extend to the sacrum and may manifest as painful swelling within the sacrococcygeal region. Typical findings on Computed Tomography (CT) include an expansile lesion accompanied by peripheral calcification. Magnetic Resonance Imaging (MRI) may serve as an excellent imaging tool for assessment of osseous extent and soft tissue involvement. Both surgery and irradiation may be utilized for management of chordomas [3-11]. Irradiation may be used as an adjuvant or alternative therapeutic approach. External Beam Radiation Therapy (EBRT), particule therapy, and stereotactic RT techniques may be utilized for effective management. While using higher doses for irradiation may contribute to improved local control outcomes, toxicity profile of radiation delivery should also be taken into account to maintain patient’s quality of life. Several advances have taken place in technology in the millennium era.

Molecular imaging methods, Image Guided RT (IGRT), automatic segmentation techniques, Intensity Modulated RT (IMRT), stereotactic RT, and Adaptive RT (ART) have been introduced for optimal radiotherapeutic management of patients [12-49]. Admittedly, improved treatment outcomes may solely be achieved through close collaboration among related disciplines for cancer management. Tumor boards may significantly contribute to bringing together surgical oncologists, radiation oncologists, medical oncologists, imaging and other relevant specialists to discuss about patient, tumor, and treatment characteristics. While surgery remains to play a major role for successful management of sacrococcygeal chordomas, irradiation may serve as a complementary or alternative therapeutic strategy in certain circumstances. In the current study, we aimed at assessing target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI. At our Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences, we have long been treating a high patient population from several places from Turkey and abroad. Within this context, several benign and malignant tumors have been irradiated at our tertiary cancer center for decades. The primary objective of the current study was focused on target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI. All included patients were referred for RT at Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences for sacrococcygeal chordoma.

We have performed a comparative analysis of target definition by CT simulation images for radiation treatment planning and with MRI. CT simulations of the patients were performed at CT-simulator (GE Lightspeed RT, GE Healthcare, Chalfont St. Giles, UK) available at our institution. Also, MRI of patients have been acquired and used for comparative assessment. A Linear Accelerator (LINAC) with the capability of contemporary IGRT techniques has been utilized for irradiation. After rigid patient immobilization, planning CT images have been acquired at CT simulator for radiation treatment planning. Thereafter, acquired RT planning images have been transferred to the contouring workstation via the network. Treatment volumes and critical organs have been defined on these images and structure sets have been generated. Also, target definition has also been performed on MRI for comparison. All patients have been treated by using state of the art RT techniques at Department of Radiation Oncology at Gulhane Medical Faculty, University of Health Sciences. This original research article has been designated for reappraisal of target definition for sacrococcygeal chordomas with comparative evaluation of CT and MRI. Irradiation procedures have been carried out at our Radiation Oncology Department of Gulhane Medical Faculty at University of Health Sciences, Ankara. Prior to treatment, all included patients have been individually evaluated by a multidisciplinary team of experts from surgical oncology and radiation oncology.

We considered the reports by American Association of Physicists in Medicine (AAPM) and International Commission on Radiation Units and Measurements (ICRU) for accurate radiation treatment planning. Radiation physicists have generated radiation treatment plans by taking into account the relevant normal tissue dose limitations through meticulous consideration of contemporary guidelines and clinical experience. Tissue heterogeneity, electron density, CT number and HU values in CT images have also been considered by radiation physicists for precise radiation treatment planning. Main endpoint of radiation treatment planning has been to achieve optimal target coverage without violation of normal tissue dose constraints. Image Guided Radiotherapy (IGRT) techniques including kilovoltage cone beam CT and electronic digital portal imaging have been used, and radiation treatment was performed by Synergy (Elekta, UK) LINAC. As the main result of this study, we have found that CT and MRI defined target definition resulted in differences. Thus, fusion of CT and MRI has been utilized for ground truth target volume determination. In the context of radiation oncology, optimal target definition and critical organ sparing may be considered among the critical components of optimal radiotherapeutic management. While definition of larger treatment volumes could lead to excessive radiation induced toxicity, definition of smaller treatment volumes may result in treatment failures. Adaptive RT strategies and multimodality imaging-based target definition have been suggested for achieving improved outcomes [50-102]. In this study, we have found that CT and MRI defined target definition resulted in differences. Thus, fusion of CT and MRI has been utilized for ground truth target volume determination.

Our results may have implications for implementation of multimodality imaging for target definition of sacrococcygeal chordomas despite the need for further supporting evidence.

There are no conflicts of interest and no acknowledgements.

1. Gui X, Siddiqui NH, Guo M (2004) Physaliphorous cells in chordoma. Arch Pathol Lab Med 128(12): 1457-1458.
2. Cha YJ, Suh YL (2019) Chordomas: Histopathological Study in View of Anatomical Location. J Korean Med Sci 34(13): e107.
3. Yadav SK, Kunal K, Kantiwal P, Rajnish RK, Elhence A, et al. (2023) Sacrococcygeal chordoma-illustrative cases and our experience. Int J Burns Trauma 13(3): 110-115.
4. Agrawal PP, Bahadur AK, Mohanta PK, Singh K, Rathi AK (2006) Chordoma: 6 years' experience at a tertiary centre. Australas Radiol 50(3): 201-205.
5. Ho BS, Nei WL (2023) Treatment Response of Sacrococcygeal Chordoma to Palliative Stereotactic Body Radiotherapy: A Case Report. Case Rep Oncol 16(1): 315-324.
6. Garcia Mora M, Mariño IF, Puerto Horta LJ, Gonzalez F, Diaz Casas S (2021) The Surgical Approach Combined with Minimally Invasive Surgery for Sacral Chordoma. Cureus 13(10): e18690.
7. Lu S, Peng X, Zou B, Zhou C, Feng M, et al. (2019) Adjuvant gamma knife surgery and image-guided, intensity-modulated radiation therapy for the treatment of sacral chordomas. Rep Pract Oncol Radiother 24(1): 74-79.
8. Denaro L, Berton A, Ciuffreda M, Loppini M, Candela V, et al. (2020) Surgical management of chordoma: A systematic review. J Spinal Cord Med 43(6): 797-812.
9. Ahmed AT, Abdel-Rahman O, Morsy M, Mustafa K, Testini P, et al (2018) Management of Sacrococcygeal Chordoma: A Systematic Review and Meta-analysis of Observational Studies. Spine Phila Pa 1976 43(19): E1157-E1169.
10. Preda L, Stoppa D, Fiore MR, Fontana G, Camisa S, et al. (2018) MRI evaluation of sacral chordoma treated with carbon ion radiotherapy alone. Radiother Oncol 128(2): 203-208.
11. Uhl M, Welzel T, Jensen A, Ellerbrock M, Haberer T, et al. (2015) Carbon ion beam treatment in patients with primary and recurrent sacrococcygeal chordoma. Strahlenther Onkol 191(7): 597-603.
12. Sager O, Dincoglan F, Demiral S, Gamsiz H, Uysal B, et al. (2022) Optimal timing of thoracic irradiation for limited stage small cell lung cancer: Current evidence and future prospects. World J Clin Oncol 13: 116-124.
13. Demiral S, Sager O, Dincoglan F, Uysal B, Gamsiz H, et al. (2021) Evaluation of breathing-adapted radiation therapy for right-sided early-stage breast cancer patients. Indian J Cancer 58: 195-200.
14. Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, et al. (2021) Omission of Radiation Therapy (RT) for Metaplastic Breast Cancer (MBC): A Review Article. International Journal of Research Studies in Medical and Health Sciences 6: 10-15.
15. Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, et al. (2021) Concise review of stereotactic irradiation for pediatric glial neoplasms: Current concepts and future directions. World J Methodol 11: 61-74.
16. Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, et al. (2020) Adaptive radiation therapy of breast cancer by repeated imaging during irradiation. World J Radiol 12: 68-75.
17. Sager O, Beyzadeoglu M, Dincoglan F, Demiral S, Gamsiz H, et al. (2020) Multimodality management of cavernous sinus meningiomas with less extensive surgery followed by subsequent irradiation: Implications for an improved toxicity profile. J Surg Surgical Res 6: 056-061.
18. Beyzadeoglu M, Sager O, Dincoglan F, Demiral S, Uysal B, et al. (2020) Single Fraction Stereotactic Radiosurgery (SRS) versus Fractionated Stereotactic Radiotherapy (FSRT) for Vestibular Schwannoma (VS). J Surg Surgical Res 6: 062-066.
19. Dincoglan F, Beyzadeoglu M, Sager O, Demiral S, Uysal B, et al. (2020) A Concise Review of Irradiation for Temporal Bone Chemodectomas (TBC). Arch Otolaryngol Rhinol 6: 016-020.
20. Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, et al. (2019) Utility of Molecular Imaging with 2-Deoxy-2-[Fluorine-18] Fluoro-DGlucose Positron Emission Tomography (18F-FDG PET) for Small Cell Lung Cancer (SCLC): A Radiation Oncology Perspective. Curr Radiopharm 12: 4-10.
21. Dincoglan F, Sager O, Demiral S, Gamsiz H, Uysal B, et al. (2019) Fractionated stereotactic radiosurgery for locally recurrent brain metastases after failed stereotactic radiosurgery. Indian J Cancer 56: 151-156.
22. Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, et al. (2019) Breathing adapted radiation therapy for leukemia relapse in the breast: A case report. World J Clin Oncol 10: 369-374.
23. Dincoglan F, Sager O, Uysal B, Demiral S, Gamsiz H, et al. (2019) Evaluation of hypofractionated stereotactic radiotherapy (HFSRT) to the resection cavity after surgical resection of brain metastases: A single center experience. Indian J Cancer 56: 202-206.
24. Sager O, Dincoglan F, Uysal B, Demiral S, Gamsiz H, et al. (2018) Evaluation of adaptive radiotherapy (ART) by use of replanning the tumor bed boost with repeated computed tomography (CT) simulation after whole breast irradiation (WBI) for breast cancer patients having clinically evident seroma. Jpn J Radiol 36: 401-406.
25. Demiral S, Dincoglan F, Sager O, Uysal B, Gamsiz H, et al. (2018) Contemporary Management of Meningiomas with Radiosurgery. Int J Radiol Imaging Technol 80: 187-190.
26. Sager O, Dincoglan F, Uysal B, Demiral S, Gamsiz H, et al. (2017) Splenic Irradiation: A Concise Review of the Literature. J App Hem Bl Tran 1: 101.
27. Dincoglan F, Sager O, Demiral S, Uysal B, Gamsiz H, et al. (2017) Radiosurgery for recurrent glioblastoma: A review article. Neurol Disord Therap 1: 1-5.
28. Demiral S, Dincoglan F, Sager O, Gamsiz H, Uysal B, et al. (2016) Hypofractionated stereotactic radiotherapy (HFSRT) for who grade I anterior clinoid meningiomas (ACM). Jpn J Radiol 34: 730-737.
29. Dincoglan F, Beyzadeoglu M, Sager O, Demiral S, Gamsiz H, et al. (2015) Management of patients with recurrent glioblastoma using hypofractionated stereotactic radiotherapy. Tumori 101: 179-184.
30. Gamsiz H, Beyzadeoglu M, Sager O, Demiral S, Dincoglan F, et al. (2015) Evaluation of stereotactic body radiation therapy in the management of adrenal metastases from non-small cell lung cancer. Tumori 101: 98-103.
31. Sager O, Beyzadeoglu M, Dincoglan F, Demiral S, Uysal B, et al. (2015) Adaptive splenic radiotherapy for symptomatic splenomegaly management in myeloproliferative disorders. Tumori 101: 84-90.
32. Sager O, Dincoglan F, Beyzadeoglu M (2015) Stereotactic radiosurgery of glomus jugulare tumors: Current concepts, recent advances and future perspectives. CNS Oncol 4: 105-114.
33. Sager O, Beyzadeoglu M, Dincoglan F, Uysal B, Gamsiz H, et al. (2014) Evaluation of linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) for cerebral cavernous malformations: A 15-year single-center experience. Ann Saudi Med 34: 54-58.
34. Demiral S, Beyzadeoglu M, Sager O, Dincoglan F, Gamsiz H, et al. (2014) Evaluation of Linear Accelerator (LINAC)-Based Stereotactic Radiosurgery (SRS) for the Treatment of Craniopharyngiomas. UHOD-Uluslararasi Hematoloji Onkoloji Dergisi 24(2): 123-129.
35. Sager O, Beyzadeoglu M, Dincoglan F, Gamsiz H, Demiral S, et al. (2014) Evaluation of linear accelerator-based stereotactic radiosurgery in the management of glomus jugulare tumors. Tumori 100: 184-188.
36. Ozsavaş EE, Telatar Z, Dirican B, Sager O, Beyzadeoğlu M (2014) Automatic segmentation of anatomical structures from CT scans of thorax for RTP. Comput Math Methods Med 2014: 472890.
37. Gamsiz H, Beyzadeoglu M, Sager O, Dincoglan F, Demiral S, et al. (2014) Management of pulmonary oligometastases by stereotactic body radiotherapy. Tumori 100: 179-183.
38. Dincoglan F, Sager O, Gamsiz H, Uysal B, Demiral S, et al. (2014) Management of patients with ≥ 4 brain metastases using stereotactic radiosurgery boost after whole brain irradiation. Tumori 100: 302-306.
39. Sager O, Beyzadeoglu M, Dincoglan F, Demiral S, Uysal B, et al. (2013) Management of vestibular schwannomas with linear accelerator-based stereotactic radiosurgery: a single center experience. Tumori 99: 617-622.
40. Dincoglan F, Beyzadeoglu M, Sager O, Uysal B, Demiral S, et al. (2013) Evaluation of linear accelerator-based stereotactic radiosurgery in the management of meningiomas: A single center experience. J BUON 18: 717-722.
41. Dincoglan F, Beyzadeoglu M, Sager O, Oysul K, Kahya YE, et al. (2013) Dosimetric evaluation of critical organs at risk in mastectomized left-sided breast cancer radiotherapy using breath-hold technique. Tumori 99: 76-82.
42. Demiral S, Beyzadeoglu M, Uysal B, Oysul K, Kahya YE, et al. (2013) Evaluation of stereotactic body radiotherapy (SBRT) boost in the management of endometrial cancer. Neoplasma 60: 322-327.
43. Sager O, Beyzadeoglu M, Dincoglan F, Oysul K, Kahya YE, et al. (2012) Evaluation of active breathing control-moderate deep inspiration breath-hold in definitive non-small cell lung cancer radiotherapy. Neoplasma 59: 333-340.
44. Saǧer Ö, Dinçoǧlan F, Gamsiz H, Demiral S, Uysal B, et al. (2012) Evaluation of the impact of integrated [18f]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography imaging on staging and radiotherapy treatment volume definition of nonsmall cell lung cancer. Gulhane Med J 54: 220-227.
45. Sager O, Beyzadeoglu M, Dincoglan F, Oysul K, Kahya YE, et al. (2012) The Role of Active Breathing Control-Moderate Deep Inspiration Breath-Hold (ABC-mDIBH) Usage in non-Mastectomized Left-sided Breast Cancer Radiotherapy: A Dosimetric Evaluation UHOD - Uluslararasi Hematoloji-Onkoloji Dergisi 22: 147-155.
46. Dincoglan F, Sager O, Gamsiz H, Uysal B, Demiral S, et al. (2012) Stereotactic radiosurgery for intracranial tumors: A single center experience. Gulhane Med J 54: 190-198.
47. Dincoglan F, Beyzadeoglu M, Sager O, Oysul K, Sirin S et al. (2012) Image-guided positioning in intracranial non-invasive stereotactic radiosurgery for the treatment of brain metastasis. Tumori 98: 630-635.
48. Sirin S, Oysul K, Surenkok S, Sager O, Dincoglan F, et al. (2011) Linear accelerator-based stereotactic radiosurgery in recurrent glioblastoma: A single center experience. Vojnosanit Pregl 68: 961-966.
49. Beyzadeoglu M, Demiral S, Dincoglan F, Sager O (2023) Evaluation of Target Definition for Radiotherapeutic Management of Recurrent Merkel Cell Carcinoma (MCC). Canc Therapy & Oncol Int J 24(2): 556133.
50. Dincoglan F, Demiral S, Sager O, Beyzadeoglu M (2023) Reappraisal of Treatment Volume Determination for Recurrent Gastroesophageal Junction Carcinoma (GJC). Biomed J Sci & Tech Res 50(5): 42061-42066.
51. Beyzadeoglu M, Dincoglan F, Demiral S, Sager O (2023) An Original Article Revisiting the Utility of Multimodality Imagıng For Refıned Target Volume Determinatıon Of Recurrent Kidney Carcinoma. Canc Therapy & Oncol Int J 23(5): 556122.
52. Beyzadeoglu M, Demiral S, Dincoglan F, Sager O (2023) Appraisal of Target Definition for Recurrent Cancers of the Supralottic Larynx. Biomed J Sci & Tech Res 50(5): 42131-42136.
53. Beyzadeoglu M, Demiral S, Dincoglan F, Sager O (2022) Assessment of Target Definition for Extramedullary Soft Tissue Plasmacytoma: Use of Multımodalıty Imaging for Improved Targeting Accuracy. Canc Therapy & Oncol Int J 22(4): 556095.
54. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2022) Target Volume Determination for Recurrent Uterine Carcinosarcoma: An Original Research Article Revisiting the Utility of Multimodality Imaging. Canc Therapy & Oncol Int J 22(3): 556090.
55. Demiral S, Sager O, Dincoglan F, Beyzadeoglu M (2022) Reappraisal of Computed Tomography (CT) And Magnetic Resonance Imaging (MRI) Based Target Definition for Radiotherapeutic Management of Recurrent Anal Squamous Cell Carcinoma (ASCC): An Original Article. Canc Therapy & Oncol Int J 22(2): 556085.
56. Demiral S, Dincoglan F, Sager O, Beyzadeoglu M (2022) An Original Article for Assessment of Multimodality Imaging Based Precise Radiation Therapy (Rt) in the Management of Recurrent Pancreatic Cancers. Canc Therapy & Oncol Int J 22(1): 556078.
57. Sager O, Demiral S, Dincoglan F, Beyzadeoglu M (2022) Assessment of Target Volume Definition for Precise Radiotherapeutic Management of Locally Recurrent Biliary Tract Cancers: An Original Research Article. Biomed J Sci & Tech Res 46(1): 37054-37059.
58. Sager O, Demiral S, Dincoglan F, Beyzadeoglu M. (2022) Radiation Therapy (RT) Target Volume Determination for Locally Advanced Pyriform Sinus Carcinoma: An Original Research Article Revisiting the Role of Multimodality Imaging. Biomed J Sci & Tech Res 45(1): 36155-36160.
59. Demiral S, Sager O, Dincoglan F, Beyzadeoglu M (2022) Improved Target Volume Definition for Radiotherapeutic Management of Parotid Gland Cancers by use of Multimodality Imaging: An Original Article. Canc Therapy & Oncol Int J 21(3): 556062.
60. Beyzadeoglu M, Sager O, Demiral S, Dincoglan F (2022) Reappraisal of multimodality imaging for improved Radiation Therapy (RT) target volume determination of recurrent Oral Squamous Cell Carcinoma (OSCC): An original article. J Surg Surgical Res 8: 004-008.
61. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2022) Multimodality imaging-based treatment volume definition for recurrent Rhabdomyosarcomas of the head and neck region: An original article. J Surg Surgical Res 8(2): 013-018.
62. Dincoglan F, Demiral S, Sager O, Beyzadeoglu M (2022) Appraisal of Target Definition for Management of Paraspinal Ewing Tumors with Modern Radiation Therapy (RT): An Original Article. Biomed J Sci & Tech Res 44(4): 35691-35696.
63. Beyzadeoglu M, Sager O, Demiral S, Dincoglan F (2022) Assessment of Target Volume Definition for Contemporary Radiotherapeutic Management of Retroperitoneal Sarcoma: An Original Article. Biomed J Sci & Tech Res 44(5): 35883-35887.
64. Demiral S, Dincoglan F, Sager O, Beyzadeoglu M (2021) Assessment of Multimodality Imaging for Target Definition of Intracranial Chondrosarcomas. Canc Therapy Oncol Int J 18: 001-005.
65. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2021) Impact of Multimodality Imaging to Improve Radiation Therapy (RT) Target Volume Definition for Malignant Peripheral Nerve Sheath Tumor (MPNST). Biomed J Sci Tech Res 34: 26734-26738.
66. Sager O, Demiral S, Dincoglan F, Beyzadeoglu M (2021) Multimodality Imaging Based Treatment Volume Definition for Reirradiation of Recurrent Small Cell Lung Cancer (SCLC). Arch Can Res 9: 1-5.
67. Demiral S, Sager O, Dincoglan F, Beyzadeoglu M (2021) Radiation Therapy (RT) Target Volume Definition for Peripheral Primitive Neuroectodermal Tumor (PPNET) by Use of Multimodality Imaging: An Original Article. Biomed J Sci & Tech Res 34: 26970-26974.
68. Dincoglan F, Demiral S, Sager O, Beyzadeoglu M (2021) Evaluation of Target Definition for Management of Myxoid Liposarcoma (MLS) with Neoadjuvant Radiation Therapy (RT). Biomed J Sci Tech Res 33: 26171-26174.
69. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2021) Radiation Therapy (RT) target determination for irradiation of bone metastases with soft tissue component: Impact of multimodality imaging. J Surg Surgical Res 7: 042-046.
70. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2021) Evaluation of Changes in Tumor Volume Following Upfront Chemotherapy for Locally Advanced Non-Small Cell Lung Cancer (NSCLC). Glob J Cancer Ther 7: 031-034.
71. Sager O, Demiral S, Dincoglan F, Beyzadeoglu M (2021) Assessment of posterior fossa target definition by multimodality imaging for patients with medulloblastoma. J Surg Surgical Res 7: 037-041.
72. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2021) Assessment of the role of multimodality imaging for treatment volume definition of intracranial ependymal tumors: An original article. Glob J Cancer Ther 7: 043-045.
73. Beyzadeoglu M, Dincoglan F, Demiral S, Sager O (2020) Target Volume Determination for Precise Radiation Therapy (RT) of Central Neurocytoma: An Original Article. International Journal of Research Studies in Medical and Health Sciences 5: 29-34.
74. Dincoglan F, Demiral S, Sager O, Beyzadeoglu M (2020) Utility of Multimodality Imaging Based Target Volume Definition for Radiosurgery of Trigeminal Neuralgia: An Original Article. Biomed J Sci & Tech Res 26: 19728-19732.
75. Demiral S, Beyzadeoglu M, Dincoglan F, Sager O (2020) Assessment of Target Volume Definition for Radiosurgery of Atypical Meningiomas with Multimodality Imaging. Journal of Hematology and Oncology Research 3: 14-21.
76. Dincoglan F, Beyzadeoglu M, Demiral S, Sager O (2020) Assessment of Treatment Volume Definition for Irradiation of Spinal Ependymomas: An Original Article. ARC Journal of Cancer Science 6: 1-6.
77. Sager O, Demiral S, Dincoglan F, Beyzadeoglu M (2020) Target Volume Definition for Stereotactic Radiosurgery (SRS) Of Cerebral Cavernous Malformations (CCMs). Canc Therapy & Oncol Int J 15: 555917.
78. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2020) Treatment Volume Determination for Irradiation of Recurrent Nasopharyngeal Carcinoma with Multimodality Imaging: An Original Article. ARC Journal of Cancer Science 6: 18-23.
79. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2020) Assessment of Target Volume Definition for Irradiation of Hemangiopericytomas: An Original Article. Canc Therapy & Oncol Int J 17(2): 555959.
80. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2020) Evaluation of Treatment Volume Determination for Irradiation of chordoma: an Original Article. International Journal of Research Studies in Medical and Health Sciences 5(10): 3-8
81. Demiral S, Dincoglan F, Sager O, Beyzadeoglu M (2020) Multimodality Imaging Based Target Definition of Cervical Lymph Nodes in Precise Limited Field Radiation Therapy (LFRT) for Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL). ARC Journal of Cancer Science 6: 06-11.
82. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2020) Radiosurgery Treatment Volume Determination for Brain Lymphomas with and without Incorporation of Multimodality Imaging. Journal of Medical Pharmaceutical and Allied Sciences 9: 2398-2404.
83. Beyzadeoglu M, Dincoglan F, Sager O, Demiral S (2020) Determination of Radiosurgery Treatment Volume for Intracranial Germ Cell Tumors (GCTS). Asian Journal of Pharmacy. Nursing and Medical Sciences 8: 18-23.
84. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2020) Target Definition of orbital Embryonal Rhabdomyosarcoma (Rms) by Multimodality Imaging: An Original Article. ARC Journal of Cancer Science 6: 12-17.
85. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2020) Evaluation of Target Volume Determination for Irradiatıon of Pilocytic Astrocytomas: An Original Article. ARC Journal of Cancer Science 6: 1-5.
86. Demiral S, Beyzadeoglu M, Dincoglan F, Sager O (2020) Evaluation of Radiosurgery Target Volume Definition for Tectal Gliomas with Incorporation of Magnetic Resonance Imaging (MRI): An Original Article. Biomedical Journal of Scientific & Technical Research (BJSTR) 27: 20543-20547.
87. Beyzadeoglu M, Sager O, Dincoglan F, Demiral S (2019) Evaluation of Target Definition for Stereotactic Reirradiation of Recurrent Glioblastoma. Arch Can Res 7: 3.
88. Sager O, Dincoglan F, Demiral S, Gamsiz H, Uysal B, et al. (2019) Evaluation of the Impact of Magnetic Resonance Imaging (MRI) on Gross Tumor Volume (GTV) Definition for Radiation Treatment Planning (RTP) of Inoperable High-Grade Gliomas (HGGs). Concepts in Magnetic Resonance Part A 2019 Article ID 4282754.
89. Sager O, Dincoglan F, Demiral S, Gamsiz H, Uysal B, et al. (2019) Utility of Magnetic Resonance Imaging (Imaging) in Target Volume Definition for Radiosurgery of Acoustic Neuromas. Int J Cancer Clin Res 6: 119.
90. Demiral S, Sager O, Dincoglan F, Beyzadeoglu M (2019) Assessment of Computed Tomography (CT) And Magnetic Resonance Imaging (MRI) Based Radiosurgery Treatment Planning for Pituitary Adenomas. Canc Therapy & Oncol Int J 13: 555857.
91. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2019) Multimodality Imaging for Radiosurgical Management of Arteriovenous Malformations. Asian Journal of Pharmacy, Nursing and Medical Sciences 7: 7-12.
92. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2019) Evaluation of Radiosurgery Target Volume Determination for Meningiomas Based on Computed Tomography (CT) And Magnetic Resonance Imaging (MRI). Cancer Sci Res Open Access 5: 1-4.
93. Demiral S, Sager O, Dincoglan F, Beyzadeoglu M (2019) Assessment of target definition based on Multimodality imaging for Radiosurgical Management of glomus jugulare tumors (GJTs). Canc Therapy & Oncol Int J 15: 555909.
94. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2019) Incorporation of Multimodality Imaging in Radiosurgery Planning for Craniopharyngiomas: An Original Article. SAJ Cancer Sci 6: 103.
95. Demiral S, Sager O, Dincoglan F, Uysal B, Gamsiz H, et al. (2018) Evaluation of Target Volume Determination for Single Session Stereotactic Radiosurgery (SRS) of Brain Metastases. Canc Therapy & Oncol Int J 12: 555848.
96. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2023) Appraisal of Target Definition for Anaplastic Thyroid Carcinoma (ATC): An Original Article Addressing the Utility of Multimodality Imaging. Canc Therapy & Oncol Int J 24(4): 556143.
97. Demiral S, Dincoglan F, Sager O, Beyzadeoglu M (2023) Reappraisal of Treatment Volume Determination for Parametrial Boosting in Patients with Locally Advanced Cervical Cancer. Canc Therapy & Oncol Int J 24(5): 556148.
98. Demiral S, Sager O, Dincoglan F, Beyzadeoglu M (2023) Tumor Size Changes after Neoadjuvant Systemic Therapy for Advanced Oropharyngeal Squamous Cell Carcinoma. Canc Therapy & Oncol Int J 24(5): 556147.
99. Demiral S, Dincoglan F, Sager O, Beyzadeoglu M (2023) Assessment of Changes in Tumor Volume Following Chemotherapy for Nodular Sclerosıng Hodgkin Lymphoma (NSHL). Canc Therapy & Oncol Int J 24(5): 556146.
100. Sager O, Demiral S, Dincoglan F, Beyzadeoglu M (2023) Evaluation of Volumetric Changes in Transglottic Laryngeal Cancers After Induction Chemotherapy. Biomed J Sci & Tech Res 51(4): 43026-43031.
101. Dincoglan F, Sager O, Demiral S, Beyzadeoglu M (2023) An Original Research Article for Evaluation of Changes in Tumor Size After Neoadjuvant Chemotherapy in Borderline Resectable Pancreatic Ductal Adenocarcinoma. Biomed J Sci & Tech Res 52(1): 43253-43255.
102. Sager O, Dincoglan F, Demiral S, Beyzadeoglu M (2023) Assessment of Tumor Size Changes After Neoadjuvant Chemotherapy in Locally Advanced Esophageal Cancer: An Original Article. Biomed J Sci & Tech Res 52(2): 43491-43493.