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74 oral Feasibility of conformal stereotactic radiosurgery for vestibular schwannoma
$20 Wednesday, 31 January 2001
bone metastases. 72
oral
Experiences with a teleradiology system to assist radiotherapy S. Hashimoto 1, H. Shirato 1, Y. Watanabe 1, T. Nishioka 1, H. Ogasawara 2 H. Segawa 2 K. Tsuchiya 1, K. Miyasaka 1 1Hokkaido University School of Medicine, Radiology, Sapporo, Japan 20taru City Hospital Radiology, Otaru, Japan Purpose: To introduce a teleradiology system for radiotherapy and to evaluate the feasibility and cost benefit of the system. Materials and methods: From Oct.1997 to Mar. 2000, 4012 images in 1073 cases were sent to the central hospital for consultation. Our system consisted of a main computer that included image server, treatment planning system, real-time TV camera, and image scanner. Each remote computer was directly connected to the image server of the central hospital through ISDN. Data security was protected by authentication system. Consultation forms and image files were compressed by 1/10 JPEG format and sent to the server. Consultants accessed to the server, checked the patientTMf records, verified the images, wrote comment on the files and sent them back to the remote hospital. Qualified radiation oncologists visited to the remote hospital in 1 to 8 days after the consultation to see the patients and evaluated the reliability of the system. Result: Clinical study and phantom study showed the image quality was acceptable for consultation. Total transmission time for one patient was 322 min. (mean 11.2). Consultation purpose was treatment verification in.. 1063 cases, confirmation of treatment policy in 3 cases, difficult diagnosis in 11 cases, assessment of quality of life (QOL) of palliative therapy in 16 cases, 3D-treatment planning in 4 cases, quality assurance (QA) of multiinstitutional clinical study in 2 cases, and for emergent radiotherapy of malignant spinal cord compression (SCC) in 12 cases. Using the system, all SCC patients recovered from paraplegia by emergent radiotherapy within 12 hours in remote hospitals. Initial equipment investment of the system was $25,000 and running cost was $2,100 per year. Cost benefit of health care insurance was between $3 and $10,000 (mean $120) for each patient. The reduction of hospitalized period was most effective value in a cost-efficient analysis. Consultation purpose was accomplished in 1051 cases (98.9%). In all cases, radiotherapy was performed safely without major corrections of radiation fields. Conclusion: This study showed that telecommunication system is a new effective technology to assist radiotherapy in remote hospitals. 73
oral
Soft tissue sarcoma after Neutron irradiation - Report from the Edinburgh Clinical Trials. R.H. MacDouaall, W. Duncan, G.R. Kerr, A. AI Nafussi Western General Hospital Department of Clinical Oncology, Edinburgh, Scotland Purpose: An analysis of cases of soft tissue sarcoma occurring after neutron irradiation. Methods: Between 1977 and 1984, the Medical Research Council supported a series of clinical trials of neutron therapy at the Cyclotron in Edinburgh. Several tumour sites were studied including randomised trials in head and neck, bladder and rectal cancer and malignant brain tumours. The results of these studies have been previously published. Patients have continued on follow up indefinitely. Results: Only 61 patients remained alive 5 years after treatment. Three of these patients have developed sarcoma within the irradiated volume (at 6,16 and 20 years post treatment). Conclusions: The high incidence of sarcoma appearing within the neutron irradiated volume several years after treatment appears significant and the possible mechanisms are being pursued. 74
oral
Feasibility of conformal stereotactic radiosurgery for vestibular schwannoma R. Wurm 1, B. REItz1, M. Pfaender 1, J. Ahlswede 1, B. Sommer 1, D, Scheffler 1, J. Bohsung 1, M. Stuschke 1, G. Grebe2, V. Budach 1 l Charite CCM, Radiation Oncology, Berlin, Germany 2TFH Berlin, University of Applied Science, Medical Physics, Berlin, Germany Purpose: Conformal Stereotactic radiosurgery (CSRS) is a high precision single isocenter radiosurgery technique using an adjustable collimator to reduce the normal tissue irradiated and allowing for a maximum dose homogeneity at the same time. This analysis seeks to describe the feasi-
Proffered papers
bility, toxicity and preliminary results of CSRS for vestibular schwannoma as primary treatment. Material and methods: From 2/1998 to 12/1999 26 patients with unilateral vestibular schwannoma (female:male ratio 17:9, median age 62 years, range: 31_+81 years, 12 left- and 14 right-sided, median volume 0.9 cc, range: 0.1-3 cc, median follow-up: 15.8 months, range: 6-29 months) received as primary treatment CSRS with 12 Gy to the tumour margin and a maximum dose inhomogeneity of 15%. Five vestibular schwannoma were localized intracanalicularly only, 12 showed both cisternal and intracanalicular growth with no brainstem contact, and 9 signs of early brainstem compression with no displacement of the fourth ventricle. Deterioration in pre-treatment impaired hearing was noted in 16% following CSRS leading to a permanent loss of hearing in 4% of patients. However, improved hearing was found in 12%, and no change in 72% of patients. A temporary facial nerve weakness was observed in 1 patient with an intracanicular schwannoma. Temporary impairment of trigeminal neuropathy present before CSRS was seen in 8%, improvement in 44%, and only 1 patient developed a temporary trigeminal neuropathy as a new complaint. Impaired dizzy-vertigo was observed in 20%, no change in 20% and improvement in 20% patients. Currently no permanent facial and trigeminat neuropathy was observed, and a decrease in tumor volume was found in 48% of patients, and in 52% of patients the tumor volume remained unchanged. Conclusion: CSRS is a feasible primary treatment for patients with small vestibular schwannoma with only minimal neurotoxicity and so far no permanent facial and trigeminal nerve complications. Our current results are in the range expected from recent reports for multiple isocenters radiosurgery using similar dose levels at the tumor margin but with lower dose homogeneity. However, further evaluation of long-term follow-up for both techniques is required. 75
oral
Radiotherapy for macular degeneration: 2 year results and overview R. Sagerman, S. Gorty, C.T. Chunq SUNY Upstate Medical University, Radiation Oncology, Syracuse, USA Purpose: To determine whether low dose irradiation was of benefit in maintaining vision for patients with choroidal neovascularization (CNV) and not treatable by laser photocoagulation. Purpose: 145 patients with subfoveal CNV, who did not meet MPS criteria for laser therapy, provided informed consent and entered a prospective pilot study. 1600 cGy was delivered in 200 cGy daily fractions using 6 MV photons, head fixation, and isocentric technique. ETORS visual acuity was measured 3,6,12 and 24 months. Results were compared with matched untreated controls from the MPS subfoveal study. Results: Both study and MPS eyes had a steady decrease in visual acuity over the follow-up period of two years. This decrease, however, was less in the irradiated eyes and found to be significant (p-0.034) using the unpaired, two-tailed Students t test. Using Kaplan Meyer estimates, there was a 25% chance that patients would lose 6 lines by 24 months in the study group but this occurred at 12 months for the controls. Results at each follow-up point and a detailed review of the world's literature, will be presented. Conclusion: Low dose irradiation decreased the loss of visual acuity for 2 years compared with untreated controls. We believe this is an important benefit in quality of life for these eldedy people. 76
oral
Early results of the cure safety trial: coronary brachytherapy with radioactive-liquid-filled balloons P.B. Schiff*, J.Z Weinberger**, F. Trichter* C.S. Wuu* Departments of *Radiation Oncology and **Medicine Columbia University College of Physicians & Surgeons, New York, NY, USA Purpose: the general risk of restenosis after coronary artery angioplasty ranges between 22 and 44%. As a result of a study performed at our medical center that demonstrated that radiation treatment reduces the risk of neointimal hyperplasia after balloon overstretch injury of a porcine coronary artery (J. Am. Coil, Cardiol. 23: 1491-1498, 1994), numerous clinical trials have been or are being performed to better understand the potential benefit of such treatment. The Columbia University Restenosis Elimination (CURE) Safety Trial is a phase 1/11study of radiation treatment with a Re188 beta radioactive liquid system of native coronary lesions as an adjunct to conventional percutaneous revascularization. We now report our initial clinical experience in 29 patients. Methods: since September 1997, 29 patients were entered into the study. Patients with either de novo or restenotic native coronary lesions undergo-
bone metastases. 72
oral
Experiences with a teleradiology system to assist radiotherapy S. Hashimoto 1, H. Shirato 1, Y. Watanabe 1, T. Nishioka 1, H. Ogasawara 2 H. Segawa 2 K. Tsuchiya 1, K. Miyasaka 1 1Hokkaido University School of Medicine, Radiology, Sapporo, Japan 20taru City Hospital Radiology, Otaru, Japan Purpose: To introduce a teleradiology system for radiotherapy and to evaluate the feasibility and cost benefit of the system. Materials and methods: From Oct.1997 to Mar. 2000, 4012 images in 1073 cases were sent to the central hospital for consultation. Our system consisted of a main computer that included image server, treatment planning system, real-time TV camera, and image scanner. Each remote computer was directly connected to the image server of the central hospital through ISDN. Data security was protected by authentication system. Consultation forms and image files were compressed by 1/10 JPEG format and sent to the server. Consultants accessed to the server, checked the patientTMf records, verified the images, wrote comment on the files and sent them back to the remote hospital. Qualified radiation oncologists visited to the remote hospital in 1 to 8 days after the consultation to see the patients and evaluated the reliability of the system. Result: Clinical study and phantom study showed the image quality was acceptable for consultation. Total transmission time for one patient was 322 min. (mean 11.2). Consultation purpose was treatment verification in.. 1063 cases, confirmation of treatment policy in 3 cases, difficult diagnosis in 11 cases, assessment of quality of life (QOL) of palliative therapy in 16 cases, 3D-treatment planning in 4 cases, quality assurance (QA) of multiinstitutional clinical study in 2 cases, and for emergent radiotherapy of malignant spinal cord compression (SCC) in 12 cases. Using the system, all SCC patients recovered from paraplegia by emergent radiotherapy within 12 hours in remote hospitals. Initial equipment investment of the system was $25,000 and running cost was $2,100 per year. Cost benefit of health care insurance was between $3 and $10,000 (mean $120) for each patient. The reduction of hospitalized period was most effective value in a cost-efficient analysis. Consultation purpose was accomplished in 1051 cases (98.9%). In all cases, radiotherapy was performed safely without major corrections of radiation fields. Conclusion: This study showed that telecommunication system is a new effective technology to assist radiotherapy in remote hospitals. 73
oral
Soft tissue sarcoma after Neutron irradiation - Report from the Edinburgh Clinical Trials. R.H. MacDouaall, W. Duncan, G.R. Kerr, A. AI Nafussi Western General Hospital Department of Clinical Oncology, Edinburgh, Scotland Purpose: An analysis of cases of soft tissue sarcoma occurring after neutron irradiation. Methods: Between 1977 and 1984, the Medical Research Council supported a series of clinical trials of neutron therapy at the Cyclotron in Edinburgh. Several tumour sites were studied including randomised trials in head and neck, bladder and rectal cancer and malignant brain tumours. The results of these studies have been previously published. Patients have continued on follow up indefinitely. Results: Only 61 patients remained alive 5 years after treatment. Three of these patients have developed sarcoma within the irradiated volume (at 6,16 and 20 years post treatment). Conclusions: The high incidence of sarcoma appearing within the neutron irradiated volume several years after treatment appears significant and the possible mechanisms are being pursued. 74
oral
Feasibility of conformal stereotactic radiosurgery for vestibular schwannoma R. Wurm 1, B. REItz1, M. Pfaender 1, J. Ahlswede 1, B. Sommer 1, D, Scheffler 1, J. Bohsung 1, M. Stuschke 1, G. Grebe2, V. Budach 1 l Charite CCM, Radiation Oncology, Berlin, Germany 2TFH Berlin, University of Applied Science, Medical Physics, Berlin, Germany Purpose: Conformal Stereotactic radiosurgery (CSRS) is a high precision single isocenter radiosurgery technique using an adjustable collimator to reduce the normal tissue irradiated and allowing for a maximum dose homogeneity at the same time. This analysis seeks to describe the feasi-
Proffered papers
bility, toxicity and preliminary results of CSRS for vestibular schwannoma as primary treatment. Material and methods: From 2/1998 to 12/1999 26 patients with unilateral vestibular schwannoma (female:male ratio 17:9, median age 62 years, range: 31_+81 years, 12 left- and 14 right-sided, median volume 0.9 cc, range: 0.1-3 cc, median follow-up: 15.8 months, range: 6-29 months) received as primary treatment CSRS with 12 Gy to the tumour margin and a maximum dose inhomogeneity of 15%. Five vestibular schwannoma were localized intracanalicularly only, 12 showed both cisternal and intracanalicular growth with no brainstem contact, and 9 signs of early brainstem compression with no displacement of the fourth ventricle. Deterioration in pre-treatment impaired hearing was noted in 16% following CSRS leading to a permanent loss of hearing in 4% of patients. However, improved hearing was found in 12%, and no change in 72% of patients. A temporary facial nerve weakness was observed in 1 patient with an intracanicular schwannoma. Temporary impairment of trigeminal neuropathy present before CSRS was seen in 8%, improvement in 44%, and only 1 patient developed a temporary trigeminal neuropathy as a new complaint. Impaired dizzy-vertigo was observed in 20%, no change in 20% and improvement in 20% patients. Currently no permanent facial and trigeminat neuropathy was observed, and a decrease in tumor volume was found in 48% of patients, and in 52% of patients the tumor volume remained unchanged. Conclusion: CSRS is a feasible primary treatment for patients with small vestibular schwannoma with only minimal neurotoxicity and so far no permanent facial and trigeminal nerve complications. Our current results are in the range expected from recent reports for multiple isocenters radiosurgery using similar dose levels at the tumor margin but with lower dose homogeneity. However, further evaluation of long-term follow-up for both techniques is required. 75
oral
Radiotherapy for macular degeneration: 2 year results and overview R. Sagerman, S. Gorty, C.T. Chunq SUNY Upstate Medical University, Radiation Oncology, Syracuse, USA Purpose: To determine whether low dose irradiation was of benefit in maintaining vision for patients with choroidal neovascularization (CNV) and not treatable by laser photocoagulation. Purpose: 145 patients with subfoveal CNV, who did not meet MPS criteria for laser therapy, provided informed consent and entered a prospective pilot study. 1600 cGy was delivered in 200 cGy daily fractions using 6 MV photons, head fixation, and isocentric technique. ETORS visual acuity was measured 3,6,12 and 24 months. Results were compared with matched untreated controls from the MPS subfoveal study. Results: Both study and MPS eyes had a steady decrease in visual acuity over the follow-up period of two years. This decrease, however, was less in the irradiated eyes and found to be significant (p-0.034) using the unpaired, two-tailed Students t test. Using Kaplan Meyer estimates, there was a 25% chance that patients would lose 6 lines by 24 months in the study group but this occurred at 12 months for the controls. Results at each follow-up point and a detailed review of the world's literature, will be presented. Conclusion: Low dose irradiation decreased the loss of visual acuity for 2 years compared with untreated controls. We believe this is an important benefit in quality of life for these eldedy people. 76
oral
Early results of the cure safety trial: coronary brachytherapy with radioactive-liquid-filled balloons P.B. Schiff*, J.Z Weinberger**, F. Trichter* C.S. Wuu* Departments of *Radiation Oncology and **Medicine Columbia University College of Physicians & Surgeons, New York, NY, USA Purpose: the general risk of restenosis after coronary artery angioplasty ranges between 22 and 44%. As a result of a study performed at our medical center that demonstrated that radiation treatment reduces the risk of neointimal hyperplasia after balloon overstretch injury of a porcine coronary artery (J. Am. Coil, Cardiol. 23: 1491-1498, 1994), numerous clinical trials have been or are being performed to better understand the potential benefit of such treatment. The Columbia University Restenosis Elimination (CURE) Safety Trial is a phase 1/11study of radiation treatment with a Re188 beta radioactive liquid system of native coronary lesions as an adjunct to conventional percutaneous revascularization. We now report our initial clinical experience in 29 patients. Methods: since September 1997, 29 patients were entered into the study. Patients with either de novo or restenotic native coronary lesions undergo-