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Shirato H, Le QT, Kobashi K, Prayongrat A, Takao S, Shimizu S, Giaccia A, Xing L, Umegaki K. Selection of external beam radiotherapy approaches for precise and accurate cancer treatment. JOURNAL OF RADIATION RESEARCH 2018; 59:i2-i10. [PMID: 29373709 PMCID: PMC5868193 DOI: 10.1093/jrr/rrx092] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Indexed: 05/05/2023]
Abstract
Physically precise external-beam radiotherapy (EBRT) technologies may not translate to the best outcome in individual patients. On the other hand, clinical considerations alone are often insufficient to guide the selection of a specific EBRT approach in patients. We examine the ways in which to compare different EBRT approaches based on physical, biological and clinical considerations, and how they can be enhanced with the addition of biophysical models and machine-learning strategies. The process of selecting an EBRT modality is expected to improve in tandem with knowledge-based treatment planning.
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Affiliation(s)
- Hiroki Shirato
- Department of Radiation Medicine, Faculty of Medicine, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Corresponding author. Department of Radiation Medicine, Faculty of Medicine, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan. Tel: +81-11-706-5977; Fax: +81-11-706-7876;
| | - Quynh-Thu Le
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Keiji Kobashi
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Japan
| | - Anussara Prayongrat
- Department of Radiation Medicine, Faculty of Medicine, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
| | - Seishin Takao
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Japan
| | - Shinichi Shimizu
- Department of Radiation Medicine, Faculty of Medicine, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
| | - Amato Giaccia
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Lei Xing
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Kikuo Umegaki
- Global Station for Quantum Medical Science and Engineering, Global Institute for Cooperative Research and Education, Hokkaido University, North-15 West-7, Kita-ku, 0608638, Sapporo, Hokkaido, Japan
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Japan
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Uchida D, Shirato H, Onimaru R, Endou H, Aoyama H, Tsuchiya K, Nishioka T, Homma A, Furuta Y, Fukuda S, Miyasaka K. Long-Term Results of Ethmoid Squamous Cell or Undifferentiated Carcinoma Treated with Radiotherapy with or without Surgery. Cancer J 2005; 11:152-6. [PMID: 15969991 DOI: 10.1097/00130404-200503000-00011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Ethmoidal malignant tumors, for which intensity-modulated radiotherapy is expected to improve outcome, consist of heterogeneous pathological types. Reports about their outcome are influenced by the inclusion of favorable histology, such as adenocarcinoma and adenoid cystic carcinoma. We investigated the long-term treatment outcome of squamous cell carcinoma and undifferentiated carcinoma of the ethmoid sinus. MATERIALS AND METHODS Between August 1976 and April 2002, 25 patients (20 squamous cell carcinomas and five undifferentiated carcinomas) received radical radiotherapy or preoperative radiotherapy in our institution. One (4%) had stage T2 disease, seven (28%) had stage T3, three (12%) had stage T4a, and 14 (56%) had stage T4b. Surgery was performed in 13 patients. Radiation dose varied from 50.4 Gy in 16 fractions (50.4 Gy/16 Fr) to 65 Gy in 26 fractions with or without stereotactic boost irradiation. Eleven patients received chemotherapy consisting mainly of platinum-based compounds. RESULTS The 3- and 5-year overall survival rates for all 25 patients were 34% (95% confidence interval [CI]: 14%-54%) and 24% (CI: 6%-42%), respectively. The 3- or 5-year local progression-free rates for all patients were 48.9% and 36.7%, respectively. Visual acuity of a single eye was impaired in three patients and was lost in five patients as a result of tumor progression, but no patient had visual impairment or loss due to radiotherapy. CONCLUSION Ethmoid squamous cell carcinoma or undifferentiated carcinoma was diagnosed at advanced T stages and was treated with radiotherapy; these patients had a poorer outcome than patients with adenocarcinoma or adenoid cystic carcinoma. Prospective trials using advanced technology should be carefully compared with historical controls because pathological types can considerably influence the treatment results.
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Affiliation(s)
- Daichi Uchida
- Department of Radiology, Department of Otorhinolaryngology, Hokkaido University School of Medicine, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
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Hida K, Shirato H, Isu T, Seki T, Onimaru R, Aoyama H, Ushikoshi S, Miyasaka K, Iwasaki Y. Focal fractionated radiotherapy for intramedullary spinal arteriovenous malformations: 10-year experience. J Neurosurg 2003; 99:34-8. [PMID: 12859056 DOI: 10.3171/spi.2003.99.1.0034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Radiosurgical treatment of spinal arteriovenous malformations (AVMs) is becoming a practical therapeutic option as methodology improves, but no comparative study has yet been published on focal fractionated radiotherapy. The authors report their experience with conventional and hypofractionated radiotherapy for spinal AVM. METHODS Candidates for this study were patients who experienced symptoms due to an intramedullary AVM but were ineligible for embolization or surgery. Of 21 patients with spinal AVMs, 10 cases in a 10-year period met this criterion. Angiography and contrast-enhanced computerized tomography scanning were used for treatment planning in all cases. Fractionated radiotherapy was performed using a linear accelerator, extracranial immobilization system, and frequent orthogonal linacographic verification. The starting radiation dose was 32 Gy in two, 36 Gy in three, and 40 Gy in two patients, in a regimen involving 1.8 to 2-Gy daily fractions; this was recently changed to a hypofractionation schedule of 30 Gy (in eight sessions) in one and 20 Gy (in four sessions) in two patients. RESULTS The follow-up period ranged from 26 to 124 months (median of 49 months). There were no hemorrhages nor any adverse reactions attributable to irradiation. Of the seven patients who consented to undergo follow-up angiography, the nidus size decreased in five, but complete obliteration did not occur in any patient. CONCLUSIONS Because no patient experienced adverse effects, the maximum tolerable radiation dose for the spinal cord associated with an AVM could not be identified, although it presumably is higher than those administered. The lack of rebleeding in patients in whom complete angiographic occlusion was absent suggests that the natural history of spinal AVMs may be less aggressive than previously reported.
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Affiliation(s)
- Kazutoshi Hida
- Department of Neurosurgery, University of Hokkaido, Graduate School of Medicine, Sapporo, Japan.
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Shirato H, Shimizu S, Kitamura K, Nishioka T, Kagei K, Hashimoto S, Aoyama H, Kunieda T, Shinohara N, Dosaka-Akita H, Miyasaka K. Four-dimensional treatment planning and fluoroscopic real-time tumor tracking radiotherapy for moving tumor. Int J Radiat Oncol Biol Phys 2000; 48:435-42. [PMID: 10974459 DOI: 10.1016/s0360-3016(00)00625-8] [Citation(s) in RCA: 307] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE To achieve precise three-dimensional (3D) conformal radiotherapy for mobile tumors, a new radiotherapy system and its treatment planning system were developed and used for clinical practice. METHODS AND MATERIALS We developed a linear accelerator synchronized with a fluoroscopic real-time tumor tracking system by which 3D coordinates of a 2.0-mm gold marker in the tumor can be determined every 0.03 second. The 3D relationships between the marker and the tumor at different respiratory phases are evaluated using CT image at each respiratory phase, whereby the optimum phase can be selected to synchronize with irradiation (4D treatment planning). The linac is triggered to irradiate the tumor only when the marker is located within the region of the planned coordinates relative to the isocenter. RESULTS The coordinates of the marker were detected with an accuracy of +/- 1 mm during radiotherapy in the phantom experiment. The time delay between recognition of the marker position and the start or stop of megavoltage X-ray irradiation was 0.03 second. Fourteen patients with various tumors were treated by conformal radiotherapy with a "tight" planning target volume (PTV) margin. They were surviving without relapse or complications with a median follow-up of 6 months. CONCLUSION Fluoroscopic real-time tumor tracking radiotherapy following 4D treatment planning was developed and shown to be feasible to improve the accuracy of the radiotherapy for mobile tumors.
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Affiliation(s)
- H Shirato
- Department of Radiology, Hokkaido University School of Medicine, Sapporo, Japan.
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Hashi N, Shirato H, Omatsu T, Kagei K, Nishioka T, Hashimoto S, Aoyama H, Fukuda S, Inuyama Y, Miyasaka K. The role of radiotherapy in treating squamous cell carcinoma of the external auditory canal, especially in early stages of disease. Radiother Oncol 2000; 56:221-5. [PMID: 10927141 DOI: 10.1016/s0167-8140(00)00220-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE Our intent was to investigate the role of radiotherapy in treating external auditory canal squamous cell carcinoma, especially in early stages of disease. MATERIALS AND METHODS The treatment results for 20 patients treated between 1980 and 1998 were retrospectively analyzed. Radiotherapy was used as an initial treatment without surgery in eight patients and with surgery in 12 patients. The patients treated by radiotherapy alone received 65 Gy in 26 fractions over 6.5 weeks. The patients treated with radiotherapy perioperatively received 30-75 Gy in 12-30 fractions. The follow-up period for survivors including patients died of intercurrent disease ranged from 7 to 205 months (mean: 71 months). RESULTS The 5-year survival rate calculated by the Kaplan-Meier method for all patients was 59%. According to Stell classification (Laryncol. Otol. 99 (1985) 847), the 5-year survival rates for eight patients with T1 disease and eight with T2 disease were 100 and 38%, respectively. In the eight patients with T1 disease, disease control was 100%. Local control with hearing preservation was achieved in five patients with T1 disease by radiotherapy alone. No late complications related to radiotherapy were observed. CONCLUSIONS A precise diagnosis of the disease in terms of whether or not it has invaded the bone is important in order to predict the treatment outcome. Radiotherapy with or without surgery is the treatment of choice for patients with T1-stage disease. Surgery with radiotherapy is recommended as standard care for tumors with bony invasion.
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Affiliation(s)
- N Hashi
- Department of Radiology, Hokkaido University School of Medicine, North-15 West-7, Kita-ku, Sapporo, Japan
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Shimizu S, Shirato H, Kagei K, Nishioka T, Bo X, Dosaka-Akita H, Hashimoto S, Aoyama H, Tsuchiya K, Miyasaka K. Impact of respiratory movement on the computed tomographic images of small lung tumors in three-dimensional (3D) radiotherapy. Int J Radiat Oncol Biol Phys 2000; 46:1127-33. [PMID: 10725622 DOI: 10.1016/s0360-3016(99)00352-1] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE Three-dimensional (3D) treatment planning has often been performed while patients breathe freely, under the assumption that the computed tomography (CT) images represent the average position of the tumor. We investigated the impact of respiratory movement on the free-breathing CT images of small lung tumors using sequential CT scanning at the same table position. METHODS Using a preparatory free-breathing CT scan, the patient's couch was fixed at the position where each tumor showed its maximum diameter on image. For 16 tumors, over 20 sequential CT images were taken every 2 s, with a 1-s acquisition time occurring during free breathing. For each tumor, the distance between the surface of the CT table and the posterior border of the tumor was measured to determine whether the edge of the tumor was sufficiently included in the planning target volume (PTV) during normal breathing. RESULTS In the sequential CT scanning, the tumor itself was not visible in the examination slice in 21% (75/357) of cases. There were statistically significant differences between lower lobe tumors (39.4%, 71/180) and upper lobe tumors (0%, 0/89) (p < 0.01) and between lower lobe tumors and middle lobe tumor (8.9%, 4/45) (p < 0.01) in the incidence of the disappearance of the tumor from the image. The mean difference between the maximum and minimum distances between the surface of the CT table and the posterior border of the tumor was 6.4 mm (range 2.1-24.4). CONCLUSION Three-dimensional treatment planning for lung carcinoma would significantly underdose many lesions, especially those in the lower lobe. The excess "safety margin" might call into question any additional benefit of 3D treatment. More work is required to determine how to control respiratory movement.
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Affiliation(s)
- S Shimizu
- Department of Radiology, Hokkaido University School of Medicine, Sapporo, Japan.
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Kagei K, Shirato H, Suzuki K, Isu T, Sawamura Y, Sakamoto T, Fukuda S, Nishioka T, Hashimoto S, Miyasaka K. Small-field fractionated radiotherapy with or without stereotactic boost for vestibular schwannoma. Radiother Oncol 1999; 50:341-7. [PMID: 10392821 DOI: 10.1016/s0167-8140(99)00031-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To assess the efficacy and toxicity of small-field fractionated radiotherapy with or without stereotactic boost (SB) for vestibular schwannomas. METHODS AND MATERIALS Thirty-nine patients with vestibular schwannoma were treated with irradiation between March 1991 and February 1996. Extra-meatal tumor diameters were under 30 mm. Thirty-three patients received small-field fractionated radiotherapy followed by SB. Basic dose schedule was 44 Gy in 22 fractions over 5 1/2 weeks plus 4 Gy in one session. Six patients received small-field fractionated radiotherapy only (40-44 Gy in 20-22 fractions over 5-5 1/2 weeks or 36 Gy in 20 fractions over 5 weeks).dash;p > RESULTS Follow-up ranged from 6 to 69 months (median, 24 months). Tumors decreased in size in 13 cases (33%), were unchanged in 25 (64%), and increased in one (3%). The actuarial 2-year tumor control rate was 97%. Fifteen patients had useful hearing (Gardner-Robertson class 1-2) and 25 patients had testable hearing (class 1-4) before irradiation. The 2-year actuarial rates of useful hearing preservation (free of deterioration from class 1-2 to class 3-5) were 78%. The 2-year actuarial rates of any testable hearing preservation (free of deterioration from class 1-4 to class 5) were 96%. No permanent facial and trigeminal neuropathy developed after irradiation. The 2-year actuarial incidences of facial and trigeminal neuropathies were 8% and 16%, respectively. CONCLUSIONS Small-field fractionated radiotherapy with or without SB provides excellent short-term local control and a relatively low incidence of complications for vestibular schwannoma, although further follow-up is necessary to evaluate the long-term results.
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Affiliation(s)
- K Kagei
- Department of Radiology, School of Medicine, Hokkaido University, Sapporo, Japan.
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Kitamura K, Shirato H, Sawamura Y, Suzuki K, Ikeda J, Miyasaka K. Preirradiation evaluation and technical assessment of involved-field radiotherapy using computed tomographic (CT) simulation and neoadjuvant chemotherapy for intracranial germinoma. Int J Radiat Oncol Biol Phys 1999; 43:783-8. [PMID: 10098433 DOI: 10.1016/s0360-3016(98)00488-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To investigate the importance of preirradiation mental and endocrinological evaluation, and the effectiveness of involved-field radiotherapy following neoadjuvant chemotherapy. METHODS AND MATERIALS Following etoposide and cisplatin with or without ifosfamide, 13 patients with nondisseminated disease received involved-field irradiation of 24 Gy in 12 fractions within 3 weeks and 2 patients with disseminated germinoma received 24 Gy craniospinal irradiation (CSI). CT simulation was used to cover the tumor bed. RESULTS Full-scale intelligence quotient (IQ) tests given at the time of the initial radiotherapy showed less than 90 in 7 of 11 patients who had tumors involving the neurohypophyseal region, but the 4 patients who had solitary pineal tumors showed higher scores. Panhypopituitarism was observed in 9 patients with tumors involving the neurohypophyseal region. All patients are alive without disease, with a median follow-up period of 40 months. No in-field relapse was noted after the involved-field radiotherapy. One patient experienced a recurrence outside of the planning target volume. CONCLUSION Decline of neurocognitive and endocrine functions were often seen in patients with tumors involving the hypophyseal region, but not in patients with solitary pineal germinoma before radiotherapy. Involved-field radiotherapy using 24 Gy is effective with the help of CT simulation and neoadjuvant chemotherapy.
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Affiliation(s)
- K Kitamura
- Department of Radiology, Hokkaido University School of Medicine, Sapporo, Japan
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Kitahara T, Shirato H, Nishioka T, Kagei K, Yamaguchi M, Furuya T, Watanabe Y, Takekawa N, Miyasaka K. A new mold material for customized patient positioning in radiotherapy. Radiother Oncol 1998; 47:77-9. [PMID: 9632296 DOI: 10.1016/s0167-8140(98)00003-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
MATERIALS The new material consists of polystyrene beads coated in a polymerizing substance that when dampened, hardens within 10 min. RESULTS AND CONCLUSIONS It has a density of less than a tenth of that of water and so is light-weight, a CT number of less than -800 and a minimal effect on the build-up of megavoltage photon beams.
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Affiliation(s)
- T Kitahara
- Department of Radiology, Hokkaido University Hospital, Sapporo, Japan
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Kaneko M, Shirato H, Nishioka T, Ohmori K, Takinami S, Arimoto T, Kagei K, Miyasaka K, Nakamura M. Scintigraphic evaluation of long-term salivary function after bilateral whole parotid gland irradiation in radiotherapy for head and neck tumour. Oral Oncol 1998; 34:140-6. [PMID: 9682778 DOI: 10.1016/s1368-8375(97)00087-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In 25 patients with head and neck tumour, in whom bilateral whole parotid glands were totally included in the irradiation volume, parotid gland function was estimated and compared with that of 58 non-irradiated parotid glands in 29 patients, by symptomatic grading and radioisotope (RI) sialography. Sequential follow-up by RI sialography has suggested that if the total dose to the parotid gland is less than 52 Gy or if the time-dose fractionation (TDF) value is less than 80, then partial recovery of salivary function can be expected 1 or 2 years after irradiation, even if patients show severe xerostomia during the first 6 months. Long-term recovery rarely occurs in parotid glands which have been irradiated at doses exceeding 55 Gy or with TDF values of 88 or higher. The 50% complication probability (ED50) was less than 33 Gy for subacute xerostomia during the first 6 months and 52.5 Gy for chronic xerostomia after 12 months, respectively. Although a prospective study will be required for confirmation, differences between the dose-response curves of xerostomia at subacute and chronic phases suggest a basis in different biological mechanisms.
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Affiliation(s)
- M Kaneko
- Department of Dental Radiology, School of Dentistry, Hokkaido University, Sapporo, Japan
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Nishioka T, Shirato H, Arimoto T, Kaneko M, Kitahara T, Oomori K, Yasuda M, Fukuda S, Inuyama Y, Miyasaka K. Reduction of radiation-induced xerostomia in nasopharyngeal carcinoma using CT simulation with laser patient marking and three-field irradiation technique. Int J Radiat Oncol Biol Phys 1997; 38:705-12. [PMID: 9240636 DOI: 10.1016/s0360-3016(97)00054-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE Tumor control and reduction of postirradiation xerostomia in patients with nasopharyngeal carcinoma (NPC) using the three-field irradiation technique based on the CT-based simulation with laser patient marking was investigated. METHODS AND MATERIALS Seventy-eight patients with NPC were consecutively treated between 1983 and 1993. In 33 patients treated before 1987, target volume was determined using a conventional x-ray simulator with a reference of CT images, and the primary site was treated by the conventional parallel-opposed two-field technique (Group I). In 45 patients treated from 1987, target volume was determined using a CT simulator slice by slice, the treatment field was projected onto the patient's skin by a laser beam projector mounted on a C-arm, and the primary site was irradiated by a three-fields (anterior and bilateral) technique (Group II). In Group II, the shape of each field was determined using a beam's eye view to reduce the dose to the bilateral parotid glands. The three-field technique reduced the dose to the superficial lobe of parotid gland to about two-thirds of the dose given by the two-field technique. Radiation-induced xerostomia was evaluated by clinical symptoms and radioisotope sialography. RESULTS The 5-year survival rate and disease-free survival rate were 46.6 and 31.2% in Group I, and 46.8 and 46.5% in Group II. A large variation in the volume of parotid glands were demonstrated, ranging from 9 cm3 to 61 cm3 among patients treated with CT simulation. Forty percent of the patients in Group II showed no or mild xerostomia, whereas all of the patients in Group I showed moderate to severe xerostomia (p < 0.01). The radioisotope sialography study showed that the mean secretion ratio by acid stimulation was improved from 3.8% in the Group I to 15.2% in the Group II (p < 0.01). CONCLUSIONS CT simulation was useful to determine the size and shape of each field to reduce the dose to the parotid gland, of which size varies largely among individual patients. The three-field technique based on CT simulation with laser patient markings is suggested to result in superior complication-free survival in terms of salivary dysfunction than did the conventional two-field technique with x-ray simulatior for NPC.
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Affiliation(s)
- T Nishioka
- Department of Radiology, Hokkaido University, Sapporo, Kita-ku, Japan
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Shirato H, Nishio M, Sawamura Y, Myohjin M, Kitahara T, Nishioka T, Mizutani Y, Abe H, Miyasaka K. Analysis of long-term treatment of intracranial germinoma. Int J Radiat Oncol Biol Phys 1997; 37:511-5. [PMID: 9112446 DOI: 10.1016/s0360-3016(96)00607-4] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To determine an appropriate treatment policy for intracranial germinoma. METHODS AND MATERIALS From 1976 to 1992, 51 patients with germinoma (18 with pathologically verified germinoma and 33 diagnosed as having germinoma by neuroimagings) were treated by radiation therapy. Various radiation doses and treatment fields were used. RESULTS The 10-year cause-specific survival rate for pathologically verified and unverified germinoma was 100% and 96%, respectively. Relapses were noted in four patients, three of whom died from the disease. Two of the four patients with a tumor larger than 4 cm in gross diameter experienced relapse. Two relapses occurred in a nonirradiated spinal canal and two occurred in the irradiation area treated by 25 Gy in 10 fractions and 30 Gy in 20 fractions. No relapse was noted in patients in whom the whole ventricle field was determined precisely using three-dimensional treatment planning. Five patients who were followed at an outpatient clinic experienced significant late neurocognitive dysfunction, which set in after radiotherapy. CONCLUSION After pathological confirmation, 40 Gy whole-ventricle irradiation using precise three-dimensional treatment planning is appropriate as a standard treatment for most intracranial germinoma.
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Affiliation(s)
- H Shirato
- Department of Radiology, Hokkaido University Hospital, Sapporo, Japan
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Shirato H, Takamura A, Tomita M, Suzuki K, Nishioka T, Isu T, Kato T, Sawamura Y, Miyamachi K, Abe H, Miyasaka K. Stereotactic irradiation without whole-brain irradiation for single brain metastasis. Int J Radiat Oncol Biol Phys 1997; 37:385-91. [PMID: 9069311 DOI: 10.1016/s0360-3016(96)00488-9] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE The effectiveness of stereotactic irradiation (STI) alone without whole-brain irradiation (WBI) for a single metastatic brain tumor was analyzed retrospectively. METHODS AND MATERIALS Forty-four patients with this condition were treated using radiosurgery (RS) alone or fractionated stereotactic radiotherapy (FSR) without WBI. RESULTS The initial response rate was 92% and the overall local control rate was 84% (37 of 44 patients). A total of 39% (18 of 44) of patients experienced intracranial relapse outside the initial target area. Forty-eight percent (21 of 44) of patients required salvage treatment for intracranial relapse. All 7 patients who received WBI as salvage treatment required no further salvage treatment, but 5 of the 14 patients who received salvage STI without WBI required three to four treatments for brain metastasis. Late radiation damage was not seen with initial treatment but was observed with retreatment. The overall median survival time was 261 days, with a standard error of 64 days. Actuarial survival at 12 and 24 months was 34% and 9%, respectively. The actuarial survival rate was significantly affected by the existence of active extracranial disease (p = 0.041). CONCLUSION The high response rate and short treatment period of STI alone are advantageous in the treatment of single brain metastasis in patients with active extracranial disease with WBI reserved for relapse. Because of the low complication rate, STI alone may be also useful in patients with good prognosis, without extracranial disease.
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Affiliation(s)
- H Shirato
- Department of Radiology, Hokkaido University School of Medicine, Sapporo, Japan
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Shiga T, Shirato H, Kikuchi Y, Nishioka T, Kitahara T, Terae S, Nishiyama N, Bo X, Miyasaka K. Clinical application of the computer picture archiving and communicating system to stereotactic radiosurgery. J Digit Imaging 1996; 9:119-22. [PMID: 8854261 DOI: 10.1007/bf03168606] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Stereotactic radiosurgery, a rapidly evolving technology, provides precise high-dose irradiation to brain lesions and tumors. A new method using digital subtraction angiographic images of a personal computer-image display terminal interfaced to our picture archiving and communication system (PACS) performs measurements and calculations of the coordinates of the location of the center of the lesion to be treated. The time required to calculate the coordinates was performed by three methods: hand calculation, digitizer method, and PACS method. These three coordinates were compared in 10 cases. The hand calculation method required approximately 50 minutes, the digitizer method required approximately 10 minutes, and the PACS method approximately 3 minutes. The difference is statistically significant (P < .001). The three methods were equally accurate. This type of PACS application using inexpensive personal computers interfaced more directly to a PACS is an emerging trend that facilitates wider access to images and to manipulating them for specialized applications.
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Affiliation(s)
- T Shiga
- Department of Radiology, Hokkaido University School of Medicine, Sapporo, Japan
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Takamura A, Shirato H, Saito H, Sakurai Y. Factors associated with tumor response and survival in radiosurgery for brain metastasis. Int J Clin Oncol 1996. [DOI: 10.1007/bf02347264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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