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AbstractAbstract
[en] Purpose: To determine the optimal dose and treatment outcome of patients treated with radiation for intracranial germinoma. Materials and Methods: Between 1975 and 1995, 39 patients with a diagnosis of intracranial germinoma were treated with radiation (RT) to the central nervous system. All but one pt received whole brain (WB) RT, (median dose: 3240 cGy range: 1500-4437 cGy) and a boost to the tumor volume (median total tumor volume dose: 5200 cGy, range: 3960-5950 cGy). Thirty-one pts received RT to the spine (median dose: 2500, range: 1875-3750). Eleven pts were treated with low dose RT and a tumor volume boost, (WB dose ≤ 2550 cGy, and spine dose ≤ 2160 cGy). Five pts were treated with cisplatin-based chemotherapy and low dose WB RT. Fifteen pts were biopsy-proven and 18 presented with multiple midline germinomas (MMG). Among all pts, 33% had serum or CSF positive for low levels of HCG and none of 19 (9 biopsy-proven) germinomas measured positive for AFP tumor marker. Six of 22 (27%) pts who had spine imaging or CSF cytology had evidence of tumor seeding. The male-to female-ratio was 1.4. Median age at diagnosis was 14 yrs for male pts and 9.5 yrs for females (p=.02, overall age range: 1-31 yrs). Median follow-up for survivors is 64 months (range: 1-226 months). Toxicity of treatment relative to dose was assessed. Results: The 5-yr. actuarial rate of disease-free survival (DFS) and overall survival for presumed germinomas was 97%. No pts died of germinoma. One pt died of a shunt infection who had received concurrent chemotherapy and low dose whole brain RT. Among the low dose RT alone group 6 pts received whole brain RT of ≤ 2550 cGy and 9 pts were treated with spinal RT of ≤ 2160 cGy without chemotherapy. Two of these pts had CSF cytology positive for tumor seeding. Additionally, 8 pts received a total dose to the tumor volume of ≤ 4800 cGy without chemotherapy. The 5-yr DFS was 100%. Five pts were treated with cisplatin-based chemotherapy followed by low dose RT. There were 2 CRs and 1 PR after 3 cycles, and 2 PRs after 1 cycle (chemotherapy was discontinued after 1 cycle due to ototoxicity). Among 18 pts treated with ≤ 3060 cGy WB RT (median follow-up: 35 mos), the most striking toxicity was in (4(5)) pts treated with chemotherapy who developed ototoxicity prior to RT. One pt had worsening of neuropsychological function which was present at diagnosis and 5 pts developed endocrinopathies. Among 20 pts treated with > 3060 cGy WB RT (median follow-up: 72 mos) there were 7 new or worsened neuropsychological outcomes. There were 10 pts who developed endocrinopathies. One female pt who received high dose WB RT was diagnosed with a glioblastoma multiforme within the treatment field 6 yrs after CSI. Conclusions: 1) Germinomas are highly curable with RT alone. 2.) These results suggest that low dose RT alone to the craniospinal axis (2000 cGy) and a boost to the tumor volume (4500 cGy) is effective and associated with few treatment complications. This may be more clearly indicated for pts with MMG or evidence of spinal seeding. Further experience is necessary to confirm this. 3.) The toxicity associated with high dose RT or chemotherapy and low dose RT argues against its use in germinomas
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Copyright (c) 1995 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 32(971); p. 208
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AbstractAbstract
[en] Purpose: Patients with relapsed acute myelogenous leukemia (AML), who are not eligible for bone marrow transplantation, have a poor prognosis when treated with chemotherapy alone. Total body irradiation (TBI) is an effective modality against AML when used in doses of 1000-1400 cGy with hematopoietic stem cell support. We undertook a phase I study of TBI with granulocyte-colony-stimulating factor (G-CSF) support, without stem cell support in patients with AML either in relapse or second or subsequent remission. Methods and Materials: Patients with relapsed AML, or AML in second or subsequent remission were treated in a phase I study of TBI followed by G-CSF. The first dose level was 200 cGy. After the initial cohort of patients it was clear that patients with overt leukemia did not benefit from this treatment, and subsequent patients were required to be in remission at the time of TBI. Results: Eleven patients were treated, 4 in overt relapse, and 7 in remission. 200 cGy was used in all, and dose escalation was not possible due to prolonged thrombocytopenia in all patients but one. Neutrophil recovery was adequate in those patients who remained in remission after TBI. Patients with overt leukemia had transient reduction in blast counts, but rapid recurrence of their leukemia. Patients treated in remission had short remissions, with the exception of one patient who is in remission 32 months after treatment. Conclusion: There is some antileukemic effect of TBI even at 200 cGy, though this dose appears to be too low to help a significant number of patients. If TBI is to be escalated without stem cell support, then a thrombopoietic agent will need to be used
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S0360301698003447; Copyright (c) 1998 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 42(5); p. 1113-1117
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AbstractAbstract
[en] Purpose: The purpose of this project was to review the brachytherapy experience in the pediatric population at the Joint Center for Radiation Therapy (JCRT) with respect to efficacy and morbidity. Methods and Materials: Treatment outcome was reviewed for 18 children between the ages of 6 months and 23 years who received 19 implants between 1982 and 1992 at JCRT. Fourteen children received permanent Iodine-125 seed implants placed in the operative tumor bed at the time of resection. Two children received stereotactically placed afterloaded high-activity I-125 seed brain implants, and one child received a high-activity I-125 brain implant followed by a permanent I-125 seed brain implant 3 years later. One girl received a temporary Iridium-192 volume implant for a vulvar rhabdomyosarcoma. Among the 15 permanent I-125 implants, the cases included five primary brain tumors, one metastatic brain tumor, six sarcomas, and one each of the following: suprarenal neuroblastoma, hepatoblastoma, and adenocarcinoma of the pancreas. All patients underwent surgery and most patients (15 out of 18) received external beam radiotherapy to a field that included the implant. Results: The median follow-up from the time of diagnosis for patients who remain alive is 55 months (range 24 to 119 months), and the median follow-up from the time of implant is 46 months (15 to 60 months). Disease was controlled in the area of the implant in 13 of 17 evaluable cases. Two patients experienced treatment-related morbidity; one patient developed severe desquamation related to an ''adriamycin recall reaction,'' and one patient died of postoperative complications. Conclusion: Despite the heterogeneous mix of cases, the use of brachytherapy in this pediatric population resulted in several cases of long-term disease control, and the overall morbidity was very low. Therefore, in properly selected pediatric cases, brachytherapy appears to be an efficacious adjunct to multimodality cancer management
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Copyright (c) 1995 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 32(2); p. 451-455
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AGE GROUPS, ANIMALS, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, BIOLOGICAL EFFECTS, BIOLOGICAL RADIATION EFFECTS, BODY, CENTRAL NERVOUS SYSTEM, DAYS LIVING RADIOISOTOPES, DIGESTIVE SYSTEM, DISEASES, ELECTRON CAPTURE RADIOISOTOPES, ENDOCRINE GLANDS, GLANDS, HEAVY NUCLEI, IMPLANTS, INJURIES, INTERMEDIATE MASS NUCLEI, INTERNAL CONVERSION RADIOISOTOPES, IODINE ISOTOPES, IRIDIUM ISOTOPES, IRRADIATION, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, MAMMALS, MAN, MEDICINE, MINUTES LIVING RADIOISOTOPES, MYOSARCOMAS, NEOPLASMS, NERVOUS SYSTEM, NUCLEI, ODD-EVEN NUCLEI, ODD-ODD NUCLEI, ORGANS, PRIMATES, RADIATION EFFECTS, RADIATION SOURCES, RADIOISOTOPES, SARCOMAS, VERTEBRATES, YEARS LIVING RADIOISOTOPES
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AbstractAbstract
[en] PURPOSE: To determine the impact of an external beam boost (EBB) on the outcome, relapse pattern and normal tissue toxicities of patients undergoing total-body irradiation (TBI) prior to bone marrow transplantation (BMT) for relapsed NHL. MATERIALS AND METHODS: Between 1982 and 1994, 299 patients at our institution underwent BMT for relapsed NHL. Patients underwent induction chemotherapy (CT) followed by conditioning with cyclophosphamide and 12 Gy TBI delivered in 6 fractions over 3 days. A total of 77 patients had persistent gross disease, defined as 2 cm or greater, after induction CT and received an EBB prior to BMT (EBB cohort). The median EBB dose was 28.8 Gy (range, 5-63), the median field size was 13 cm2 (range, 5-29.4) and the median time from EBB to BMT was 3 weeks (range, 1-20). A total of 222 patients were free of measurable disease or had disease measuring <2cm after CT and did not receive EBB (no-EBB cohort). To assess normal tissue toxicity, patients' simulation films and/or treatment records were reviewed for all 77 patients treated with local EBB and estimates were made of the percentage lung, heart and kidney in the radiation field. RESULTS: A total of 79 of 222 patients (36%) in the no-EBB cohort have relapsed; 33 of 77 patients (43%) in the EBB cohort have relapsed (p=0.28, by Fisher exact test). Median time to relapse after BMT was 54 months for the no-EBB cohort and 38 months for the EBB cohort (p=0.26, by log-rank test). The 3-year actuarial freedom from relapse (deaths in remission censored) was 59% for the no-EBB cohort (90% CI: 52-66%) and 51% for the EBB cohort (90% CI: 40-62%). Data on site of relapse was available for 101 of the 112 relapses (75 no-EBB, 26 EBB). For the no-EBB cohort 33 of 75 relapses (44%) were in sites of prior nodal disease only. For the EBB cohort, 12 of 26 relapses (46%) were in sites of prior nodal disease only, of these, only 6 (23%) were within the EBB treatment field. A total of 26 patients had thoracic irradiation; of these 22 patients had ≥ 25% of one lung, or ≥ 15% of both lungs irradiated. Median EBB dose to the partially irradiated lung was 37.2 Gy (range, 16-63). Seven of the 26 patients receiving thoracic radiation (27%) developed symptomatic radiation pneumonitis. Symptoms have resolved in 4 patients and 3 patients have died of pulmonary complications. A total of 21 patients had abdominal radiation; 9 of these patients had direct kidney irradiation, defined as 10% or greater of total kidney volume. The median EBB dose to the partially treated kidney was 24 Gy. None of the 9 patients who received direct kidney irradiation have developed signs of kidney injury, although 1 of the 21 patients who received abdominal radiation developed a hemolytic uremia syndrome. Six patients had ≥ 50% of the heart irradiated to a median EBB dose of 37.8 Gy (range, 32-47.8). One patient developed a pericardial effusion and constrictive pericarditis after BMT while on IL-2 therapy; this patient died of respiratory causes (included in the pulmonary complication group above). CONCLUSIONS: Patients with recurrent lymphoma with gross residual disease after reinduction chemotherapy (defined as ≥ 2cm in size in this study) have a poor prognosis following BMT. In an attempt to improve the outcome of these patients, an external beam boost was given to sites of residual gross disease prior to BMT. The efficacy of this treatment remains uncertain. Caution must be exercised when using this approach to treat residual thoracic disease, as there is a high risk of associated radiation pneumonitis. However, for patients with resistant thoracic disease, external beam boost followed by BMT may offer the only potential for cure
Primary Subject
Source
Copyright (c) 1995 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 32(971); p. 215
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ALKYLATING AGENTS, ANIMAL TISSUES, BIOLOGICAL EFFECTS, BODY, CARDIOVASCULAR SYSTEM, DISEASES, DOSES, DRUGS, EXTERNAL IRRADIATION, HEMATOPOIETIC SYSTEM, IMMUNE SYSTEM DISEASES, IMMUNOSUPPRESSIVE DRUGS, IRRADIATION, MEDICINE, NEOPLASMS, NUCLEAR MEDICINE, ORGANS, RADIATION EFFECTS, RADIOLOGY, RESPIRATORY SYSTEM, THERAPY
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AbstractAbstract
[en] Purpose: Intracranial germ cell tumors are rare, radiosensitive tumors seen most commonly in the second and third decades of life. Radiotherapy alone has been the primary treatment modality for germinomas, and is used with chemotherapy for nongerminomatous tumors. Stereotactic radiotherapy techniques minimize the volume of surrounding normal tissue irradiated and, hence, the late radiation morbidity. This study reports our experience with stereotactic radiotherapy in this group of tumors. Methods and Materials: Between December 1992 and December 1998, 18 patients with intracranial germ cell tumors were treated with stereotactic radiotherapy. A total of 23 histologically proven tumors were treated. Thirteen patients had a histologic diagnosis of germinoma, and 5 patients had germinoma with nongerminomatous elements. Of those patients with a histologic diagnosis of germinoma, 5 had multiple midline tumors. The median age of the patients was 12.9 years (range, 5.6-17.5 years). Results: A boost using stereotactic radiotherapy was delivered to 19 tumors following whole-brain radiation in 8 cases and craniospinal radiation in 11 cases. Three tumors were treated with stereotactic radiotherapy to the tumor volume alone following chemotherapy, and 1 tumor received a boost using stereotactic radiosurgery following craniospinal radiation. A median dose of 2520 cGy (range, 1500-3600) cGy was given to the whole brain, and a median dose of 2160 (range, 2100-2600) cGy was given to the spinal field. The median boost dose to the tumor was 2600 (range, 2160-3600) cGy, given by stereotactic radiotherapy delivered to the 95% isodose line. At a median follow-up time of 40 (range, 12-73) months, no local or marginal recurrences were reported in patients with germinoma. Two patients with nongerminomatous tumors have relapsed. One had elevation of tumor markers only at 37 months following treatment, and the other had persistent disease following chemotherapy and radiation therapy. Eight patients documented pituitary-hypothalamic dysfunction; in 7 (87.5%) of these patients, the dysfunction was present before commencing radiotherapy. Four patients (22%) developed newly diagnosed diabetes insipidus following surgery. Three patients (17%) received antidepressant medication at follow-up. Conclusion: Our series shows that stereotactic radiotherapy is achievable and well tolerated in this group of patients. Longer follow-up is required to fully assess the impact on long-term toxicity. Psychologic assessment of mood and affect should be performed as part of routine follow-up in this group of adolescent children
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S0360301601015693; Copyright (c) 2001 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
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International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 51(1); p. 108-112
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AbstractAbstract
[en] Purpose: In children with chiasmal gliomas, radiation therapy can arrest progressive visual and neurologic impairment. We examined the radiographic response and clinical outcomes after irradiation. Methods and Materials: Forty-two children (median age at diagnosis, 6.6 years) with chiasmal gliomas were managed as follows: 11 asymptomatic patients with neurofibromatosis-1 (NF-1) were observed only; 2 patients, less than 3 years old, underwent surgery and chemotherapy to delay irradiation; and 29 patients with progressive disease received radiation with or without prior surgery or chemotherapy. Time to radiographic response, long-term tumor control and late sequelae were reviewed for the 29 irradiated patients. Results: The probability of at least 50% radiographic response at 24 months after irradiation was 18.1% and increased to 38.2% by 48 months and 45.9% by 60 months. By actuarial analysis, the median time for such radiographic response was 62 months. For the 29 irradiated patients, the 10-year freedom from progression and overall survival rates were 100% and 89%, respectively (median follow-up for surviving patients, 108 months). Stabilization or improvement in vision occurred in 81% of 26 evaluable irradiated patients. Conclusions: Notable radiographic response may be observed years after irradiation. Radiation therapy provides excellent long-term tumor control and vision preservation or improvement in the majority of patients with progressive chiasmal gliomas
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Source
S0360301697003593; Copyright (c) 1997 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 39(3); p. 579-587
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AbstractAbstract
[en] Purpose: To determine the optimal dose and treatment outcome of patients treated with radiation for intracranial germinoma. Methods and Materials: Between 1975 and 1995, 40 patients with the diagnosis of intracranial germinoma were treated with radiation (RT) to the central nervous system. All patients received whole-brain (WB) RT (median dose: 32.4 Gy, range: 15-44.37 Gy) and a boost to the tumor volume (median total tumor volume dose: 52 Gy, range: 45-59.5 Gy). Thirty patients received RT to the spine (median dose: 26 Gy, range: 18.75-37.5 Gy). Four patients were treated with cisplatin-based chemotherapy and WB RT with a boost to the tumor volume (dose range: 51-54 Gy). A low-dose RT only group was defined as ≤25.5 Gy to the WB (9 patients); <50 Gy to the primary site (14 patients); and <22 Gy to the spine (9 patients) Seventeen tumors were biopsy-proven germinoma, and 17 patients presented with multiple midline germinomas (MMG). Among 26 patients who had tumor markers measured, 27% had elevation of β-human chorionic gonadotropin and by definition, no patient had an elevation of AFP. Twenty-four percent of 26 patients who had spine imaging or cerebral spinal fluid cytology had evidence of tumor seeding at diagnosis. The male to female ratio was 1.9:1. Median age at diagnosis was 14 years for male patients and 9.5 years for female patients (p = 0.02), (overall age ranges: 0.5-31 years). Median follow-up was 62 months (range: 3-226 months). Late effects of 29 patients with follow-up of ≥20 months and adequate documentation in their medical records were analyzed. Results: The 5-year actuarial rate of disease-free survival (DFS) and overall survival (OS) for biopsy-proven germinomas and presumed germinomas was 97%. No patient died of germinoma. There were no local failures regardless of the dose of RT, elevation of HCG tumor marker, or CSF dissemination at presentation. At presentation 22 patients had evidence of at least one endocrine abnormality. At follow-up there were no new patients diagnosed with an endocrine abnormality; however, 13 out of 22 patients had an increase in the number of endocrine deficiencies requiring hormone replacement. At presentation, 14 patients showed evidence of growth retardation. At follow-up there were no new cases of growth failure in the remaining patients. Conclusions: Germinomas are highly curable with RT alone. Lower doses of RT to the craniospinal axis without chemotherapy appear to produce equally effective DFS and OS as do higher doses of RT or combination chemotherapy and RT. Craniospinal RT may be indicated for patients with MMG or patients with evidence of spinal seeding. Long-term effects of growth retardation, and other endocrine deficiencies appear to be correlated with disease at presentation rather than solely with treatment
Primary Subject
Source
S0360301697003301; Copyright (c) 1997 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 39(2); p. 419-426
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AbstractAbstract
[en] Purpose: To examine the presentation, management, and outcome of patients with extensive intrathoracic involvement in early-stage Hodgkin's disease. Patients and Methods: One hundred seventy-two patients with clinical Stage IA-IIB Hodgkin's disease and extensive intrathoracic involvement were studied. Extensive intrathoracic disease was defined as either large mediastinal adenopathy (LMA, defined as the width of the mass greater than one-third the maximum thoracic diameter, n = 154) or as extensive (>10 cm) cephalocaudad intrathoracic disease that did not fulfill formal chest radiograph criteria for LMA (n = 18). Patients were divided into three groups based on staging and extent of treatment. Forty-seven patients were treated with radiation alone after a laparotomy (RT-lap), 47 patients received combined modality therapy after laparotomy (CMT-lap), and 78 patients were treated with combined modality therapy without staging laparotomy (CMT-no lap). MOPP was used in 82% of the CMT patients. Low-dose whole-cardiac RT was used in nearly 50% of patients treated either with RT or CMT. Results: The 10-year actuarial freedom from relapse rates were 54% with RT alone and 88% with CMT (p = 0.001); overall survival rates were 84 and 89%, respectively (p = NS). The median time to relapse was only 17 months. Over 80% of relapses occurred within the first 3 years. The most common site of relapse in all patients was the mediastinum. Relapses below the diaphragm were rare, even in CMT patients who did not receive abdominal radiation treatment. The principal acute morbidity was symptomatic pneumonitis, which occurred in 29% of patients receiving any part of their chemotherapy after RT, compared to 13% if all the chemotherapy was given before RT and 11% if RT alone was administered. There was a low late risk of myocardial infarction (3%) in the two groups with the longest follow up (RT-lap, CMT-lap), but a higher risk of second malignancy in the CMT-lap group (21%) compared with the RT-lap group (2%). Conclusion: Extensive intrathoracic involvement is a distinctive presentation of early-stage HD that has a high relapse risk if treated with RT alone. The introduction of CMT has been associated with improvements in freedom from relapse. The low rate of peripheral relapse with CMT suggests that reductions in field size may be achievable. The use of low-dose whole-heart RT with modern techniques is not associated with a high risk of late cardiac complications and should be used in patients who present with extensive pericardial disease or cardiophrenic lymphadenopathy. The high rate of second malignancy in the CMT group with the longest follow-up suggests that careful long-term surveillance for such patients is warranted
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Source
S0360301697000850; Copyright (c) 1997 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 39(2); p. 361-369
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AbstractAbstract
[en] Purpose: The patient population treated with fractionated stereotactic radiotherapy (SRT) is significantly different than that treated with stereotactic radiosurgery (SRS). Generally, lesions treated with SRT are larger, less spherical, and located within critical regions of the central nervous system; hence, they offer new challenges to the treatment planner. Here a simple, cost effective, beam shaping system has been evaluated relative to both circular collimators and an ideal dynamically conforming system for effectiveness in providing conformal therapy for these lesions. Methods and Materials: We have modeled a simple system for conformal arc therapy using four independent jaws. The jaw positions and collimator angle are changed between arcs but held fixed for the duration of each arc. Eleven previously treated SRT cases have been replanned using this system. The rectangular jaw plans were then compared to the original treatment plans which used circular collimators. The plans were evaluated with respect to tissue sparing at 100%, 80%, 50%, and 20% of the prescription dose. A plan was also done for each tumor in which the beam aperture was continuously conformed to the beams eye view projection of the tumor. This was used as an ideal standard for conformal therapy in the absence of fluence modulation. Results: For tumors with a maximum extent of over 3.5 cm the rectangular jaw plans reduced the mean volume of healthy tissue involved at the prescription dose by 57% relative to the circular collimator plans. The ideal conformal plans offered no significant further improvement at the prescription dose. The relative advantage of the rectangular jaw plans decreased at lower isodoses so that at 20% of the prescription dose tissue involvement for the rectangular jaw plans was equivalent to that for the circular collimator plans. At these isodoses the ideal conformal plans gave substantially better tissue sparing. Conclusion: A simple and economical field shaping device has been shown to provide all of the beam shaping advantage of a hypothetical ideal dynamically conforming system at the prescription level. This system may be immediately implemented in the clinic. It offers a substantial advantage over the currently used circular collimators in the high dose region with equivalent performance in the low dose region
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Source
S036030169700151X; Copyright (c) 1997 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: Argentina
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 38(5); p. 1113-1121
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Hodgson, David C.; Goumnerova, Liliana C.; Loeffler, Jay S.; Dutton, Sharon; Black, Peter McL; Alexander, Eben; Xu Ronghui; Kooy, Hanne; Silver, Barbara; Tarbell, Nancy J., E-mail: tarbell.nancy@mgh.harvard.edu2001
AbstractAbstract
[en] Objective: To describe the outcome of pediatric brain tumor patients following stereotactic radiosurgery (SRS), and factors associated with progression-free survival. Methods: We reviewed the outcome of 90 children treated with SRS for recurrent (n=62) or residual (n=28) brain tumors over a 10-year period. Median follow-up from SRS was 24 months for all patients and 55.5 months for the 34 patients currently alive. Results: The median progression-free survival (PFS) for all patients was 13 months. Median PFS according to tumor histology was medulloblastoma = 11 months, ependymoma 8.5 months, glioblastoma and anaplastic astrocytoma = 12 months. Median PFS in patients treated to a single lesion was 15.4 months. No patient undergoing SRS to more than 1 lesion survived disease free beyond 2 years. After adjusting for histology and other clinical factors, SRS for tumor recurrence (RR=2.49) and the presence of > 1 lesion (RR=2.3) were associated with a significantly increased rate of progression (p<0.05). Three-year actuarial local control (LC) was as follows: medulloblastoma = 57%, ependymoma = 29%, anaplastic astrocytoma/glioblastoma = 60%, other histologies = 56%. Nineteen patients with radionecrosis and progressive neurologic symptoms underwent reoperation after an interval of 0.6-62 months following SRS. Pathology revealed necrosis with no evidence of tumor in 9 of these cases. Conclusion: SRS can be given safely to selected children with brain tumors. SRS appears to reduce the proportion of first failures occurring locally and is associated with better outcome when given as a part of initial management. Some patients with unresectable relapsed disease can be salvaged with SRS. SRS to multiple lesions does not appear to be curative. Serious neurologic symptoms requiring reoperation is infrequently caused by radionecrosis alone
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S0360301601015188; Copyright (c) 2001 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.
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Journal Article
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD3; v. 50(4); p. 929-935
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