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1.
AJNR Am J Neuroradiol ; 43(2): 299-303, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35058296

RESUMEN

BACKGROUND AND PURPOSE: Radiation necrosis, for which abnormal WM enhancement is a hallmark, is an uncommon complication of craniospinal irradiation in children with medulloblastoma. The magnetization transfer ratio measures macromolecular content, dominated by myelin in the WM. We investigated whether the pretreatment supratentorial (nonsurgical) WM magnetization transfer ratio could predict patients at risk for radiation necrosis after radiation therapy for medulloblastoma. MATERIALS AND METHODS: Ninety-five eligible patients with medulloblastoma (41% female; mean age, 11.0 [SD, 5.4] years) had baseline balanced steady-state free precession MR imaging before proton or photon radiation therapy. Associations among baseline supratentorial magnetization transfer ratio, radiation necrosis (spontaneously resolving/improving parenchymal enhancement within the radiation field)3, age, and the presence of visible brain metastases were explored by logistic regression and parametric/nonparametric techniques as appropriate. RESULTS: Twenty-three of 95 (24.2%) children (44% female; mean age, 10.7 [SD, 6.7] years) developed radiation necrosis after radiation therapy (19 infratentorial, 1 supratentorial, 3 both). The mean pretreatment supratentorial WM magnetization transfer ratio was significantly lower in these children (43.18 versus 43.50, P = .03). There was no association between the supratentorial WM magnetization transfer ratio and age, sex, risk/treatment stratum, or the presence of visible brain metastases. CONCLUSIONS: A lower baseline supratentorial WM magnetization transfer ratio may indicate underlying structural WM susceptibility to radiation necrosis and may identify children at risk for developing radiation necrosis after craniospinal irradiation for medulloblastoma.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Cerebelosas , Meduloblastoma , Neoplasias Cerebelosas/radioterapia , Niño , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Meduloblastoma/radioterapia , Necrosis/etiología
2.
AJNR Am J Neuroradiol ; 42(12): 2245-2250, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34674998

RESUMEN

BACKGROUND AND PURPOSE: Posterior fossa type A (PFA) ependymomas have 2 molecular subgroups (PFA-1 and PFA-2) and 9 subtypes. Gene expression profiling suggests that PFA-1 and PFA-2 tumors have distinct developmental origins at different rostrocaudal levels of the brainstem. We, therefore, tested the hypothesis that PFA-1 and PFA-2 ependymomas have different anatomic MR imaging characteristics at presentation. MATERIALS AND METHODS: Two neuroradiologists reviewed the preoperative MR imaging examinations of 122 patients with PFA ependymomas and identified several anatomic characteristics, including extension through the fourth ventricular foramina and encasement of major arteries and tumor type (midfloor, roof, or lateral). Deoxyribonucleic acid methylation profiling assigned ependymomas to PFA-1 or PFA-2. Information on PFA subtype from an earlier study was also available for a subset of tumors. Associations between imaging variables and subgroup or subtype were evaluated. RESULTS: No anatomic imaging variable was significantly associated with the PFA subgroup, but 5 PFA-2c subtype ependymomas in the cohort had a more circumscribed appearance and showed less tendency to extend through the fourth ventricular foramina or encase blood vessels, compared with other PFA subtypes. CONCLUSIONS: PFA-1 and PFA-2 ependymomas did not have different anatomic MR imaging characteristics, and these results do not support the hypothesis that they have distinct anatomic origins. PFA-2c ependymomas appear to have a more anatomically circumscribed MR imaging appearance than the other PFA subtypes; however, this needs to be confirmed in a larger study.


Asunto(s)
Ependimoma , Neoplasias Infratentoriales , Estudios de Cohortes , Ependimoma/diagnóstico por imagen , Ependimoma/genética , Ependimoma/patología , Humanos , Neoplasias Infratentoriales/diagnóstico por imagen , Imagen por Resonancia Magnética , Neuroimagen
3.
Pediatr Blood Cancer ; 65(3)2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29115718

RESUMEN

BACKGROUND: Young children with posterior fossa ependymoma (PF-EPN) have a worse prognosis than older children, and they have a unique molecular profile (PF-EPN-A subtype). Alternative treatment strategies are often used in these young patients, and their prognostic factors are less clear. METHODS: We characterized the prognostic factors and treatment outcomes of 482 patients between ages 0 and 3 years with the diagnosis of ependymoma identified from the Surveillance, Epidemiology, and End Results registry (1973-2013). RESULTS: Radiation therapy (RT) was delivered to 52.3% of patients, and gross total resection (GTR) was performed in 51.0% of patients. Overall survival (OS) at 10 years was 48.4% with median follow-up of 3.3 years. WHO grade was not predictive of OS. Extent of resection was significant for survival; the 10-year OS with GTR was 61.0%, and with subtotal resection (STR) and biopsy was 38.2% and 35.0%, respectively (P < 0.001). RT significantly benefitted OS for both grades II and III. The 10-year OS for grade II was 50.5% with RT and 43.4% without (P = 0.030); 10-year OS for grade III was 66.0% with RT and 40.0% without (P = 0.002). Multivariate analysis showed significantly improved OS with RT (hazard ratio [HR] 0.601, 95% CI: 0.439-0.820, P = 0.001) and GTR (HR 0.471, 95% CI: 0.328-0.677, P < 0.0001). CONCLUSIONS: Ependymoma outcomes in patients within 0-3 years of age significantly improved with RT and GTR. Histopathologic grading of ependymoma demonstrated no prognostic significance. Given the poor OS for this population and unique genetic profile, future prospective studies with molecular-based stratification should be performed to evaluate additional prognostic factors.


Asunto(s)
Ependimoma/radioterapia , Ependimoma/cirugía , Neoplasias Infratentoriales/radioterapia , Neoplasias Infratentoriales/cirugía , Preescolar , Ependimoma/mortalidad , Femenino , Humanos , Lactante , Recién Nacido , Neoplasias Infratentoriales/mortalidad , Masculino , Pronóstico , Supervivencia sin Progresión , Programa de VERF , Resultado del Tratamiento
5.
Bone Marrow Transplant ; 50(7): 968-77, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25665048

RESUMEN

T-cell depletion of an HLA-haploidentical graft is often used to prevent GVHD, but the procedure may lead to increased graft failure, relapse and infections due to delayed immune recovery. We hypothesized that selective depletion of the CD45RA+ subset can effectively reduce GVHD through removal of naive T cells, while providing improved donor immune reconstitution through adoptive transfer of CD45RA- memory T cells. Herein, we present results from the first 17 patients with poor-prognosis hematologic malignancy, who received haploidentical donor transplantation with CD45RA-depleted progenitor cell grafts following a novel reduced intensity conditioning regimen without TBI or serotherapy. Extensive depletion of CD45RA+ T cells and B cells, with preservation of abundant memory T cells, was consistently achieved in all 17 products. Neutrophil engraftment (median day +10) and full donor chimerism (median day +11) was rapidly achieved post transplantation. Early T-cell reconstitution directly correlated with the CD45RA-depleted graft content. T-cell function recovered rapidly with broad TCR Vß spectra. There was no infection-related mortality in this heavily pretreated population, and no patient developed acute GVHD despite infusion of a median of >100 million per kilogram haploidentical T cells.


Asunto(s)
Neoplasias Hematológicas/genética , Antígenos Comunes de Leucocito/metabolismo , Adolescente , Adulto , Niño , Preescolar , Femenino , Neoplasias Hematológicas/mortalidad , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico , Linfocitos T , Adulto Joven
6.
AJNR Am J Neuroradiol ; 34(2): 446-50, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22821924

RESUMEN

SUMMARY: PT promises to reduce side effects in children with brain tumors by sparing normal tissue compared with 3D conformal or intensity-modulated radiation therapy. Information is lacking about the combined effects of PT and chemotherapy in young children. We describe imaging changes in 8 very young children with localized brain tumors who received PT after chemotherapy. Mostly transient signal abnormalities and enhancement in brain parenchyma were observed by serial MR imaging, which were consistent with radiation-induced effects on normal-appearing tissue. Correlation with PT planning data revealed that the areas of imaging abnormality were located within or adjacent to the volume that received the highest radiation dose. Radiologists should be aware of these findings in children who receive PT after chemotherapy. In this report, we describe the time course of these PT-related imaging findings and correlate them with treatment and clinical outcomes.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Quimioradioterapia/métodos , Terapia de Protones/métodos , Tumor Rabdoide/patología , Tumor Rabdoide/terapia , Teratoma/patología , Teratoma/terapia , Neoplasias Encefálicas/epidemiología , Carcinoma/epidemiología , Carcinoma/patología , Carcinoma/terapia , Neoplasias Cerebelosas/epidemiología , Neoplasias Cerebelosas/patología , Neoplasias Cerebelosas/terapia , Quimioradioterapia/efectos adversos , Preescolar , Neoplasias del Plexo Coroideo/epidemiología , Neoplasias del Plexo Coroideo/patología , Neoplasias del Plexo Coroideo/terapia , Imagen de Difusión por Resonancia Magnética , Ependimoma/epidemiología , Ependimoma/patología , Ependimoma/terapia , Femenino , Estudios de Seguimiento , Gadolinio , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Meduloblastoma/epidemiología , Meduloblastoma/patología , Meduloblastoma/terapia , Tumores Neuroectodérmicos Primitivos/epidemiología , Tumores Neuroectodérmicos Primitivos/patología , Tumores Neuroectodérmicos Primitivos/terapia , Terapia de Protones/efectos adversos , Dosis de Radiación , Tumor Rabdoide/epidemiología , Factores de Riesgo , Teratoma/epidemiología
7.
Clin Oncol (R Coll Radiol) ; 16(3): 215-22, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15191011

RESUMEN

AIMS: We have evaluated the potential for intensity-modulated radiation therapy (IMRT) to reduce dose to surrounding normal tissues in children with retinoblastoma confined to the globe of the eye. MATERIALS AND METHODS: Treatment planning computed tomography (CT) scans from five children were used for comparison of four radiotherapy techniques to treat the eye. IMRT, conformal, anterior-lateral photon and en face electron plans were generated using the Corvus (NOMOS) and PLUNC treatment planning systems. Doses to surrounding critical structures were compared after normalisation of target coverage. RESULTS: The IMRT treatment technique allowed the greatest sparing of the surrounding bony orbit, with an average of 60% of the ipsilateral bony orbit treated above 20 Gy and 48% treated above 24 Gy when 45 Gy is prescribed to the globe. IMRT techniques reduced dose to the surrounding bony orbit by more than one-third compared with anterior-lateral photon and electron techniques, and by 23% compared with conformal techniques. The application of IMRT also reduced dose to other surrounding normal tissues, including the temporal lobe and contralateral orbit. CONCLUSION: IMRT shows potential for protecting normal tissues in patients requiring external beam radiation therapy for retinoblastoma.


Asunto(s)
Neoplasias del Ojo/radioterapia , Retinoblastoma/radioterapia , Niño , Fraccionamiento de la Dosis de Radiación , Humanos , Órbita/efectos de la radiación , Traumatismos por Radiación/prevención & control , Radioterapia Conformacional , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
8.
Int J Radiat Biol ; 79(5): 359-66, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12943244

RESUMEN

PURPOSE: To elucidate the brain molecular response to irradiation. The expression of the intercellular adhesion molecule (ICAM-1) and tumour necrosis factor-alpha (TNF-alpha) in the mouse brain was compared after single-dose and fractionated whole-brain irradiation. MATERIALS AND METHODS: Mice received a single dose of 2, 10 or 20 Gy or a fractionated dose (2 Gy day(-1)) of 10, 20 or 40 Gy. ICAM-1, and TNF-alpha mRNA expression were quantified by the highly sensitive real-time polymerase chain reaction technique. Expression of ICAM-1 protein was quantified by dual-labelled monoclonal antibody assay. RESULTS: After a 20-Gy single dose, there was an increase in ICAM-1 and TNF-alpha mRNA levels (14- and 11-fold, respectively) as well as a significant increase in the level of ICAM-1 protein (p=0.0243). The expression of ICAM-1 and TNF-alpha mRNA increased at the end of the 40-Gy fractionated regimen (3.55- and 2.30-fold, respectively). CONCLUSIONS: The molecular response of the brain to single-dose irradiation was rapid, while its response to fractionated irradiation was slow. This finding is consistent with clinical observations and could be of use when designing strategies to mitigate radiation sequelae.


Asunto(s)
Encéfalo/metabolismo , Encéfalo/efectos de la radiación , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Secuencia de Bases , Fraccionamiento de la Dosis de Radiación , Expresión Génica/efectos de la radiación , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/genética , ARN Mensajero/metabolismo
9.
Ophthalmology ; 108(11): 2106-14; discussion 2114-5, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11713087

RESUMEN

PURPOSE: To evaluate the efficacy of multiagent chemotherapy in the neoadjuvant treatment of retinoblastoma. DESIGN: Noncomparative, prospective case series. PARTICIPANTS: Twenty consecutive patients with multifocal intraocular retinoblastoma (4 unilateral, 16 bilateral [36 eyes]). INTERVENTION: Eight cycles of chemotherapy with carboplatin and vincristine were administered at 3-week intervals over a 6-month period. Supplemental therapy was withheld until disease progression was documented. MAIN OUTCOME MEASURES: Disease progression (defined as tumor growth, vitreous or subretinal seed progression, and new tumor formation), delay of external beam radiotherapy, and ocular survival. RESULTS: Thirty-six eyes were treated. Eighteen eyes had Reese-Ellsworth group I-III tumors, and 16 eyes had Reese-Ellsworth group IV-V tumors at diagnosis. Two patients, who had unilateral disease at diagnosis, subsequently had tumors develop in the contralateral eye. Nineteen of 20 patients (95%) completed eight cycles of chemotherapy without disease progression. Three eyes of three different patients were successfully treated with chemotherapy alone. Thirty-three of 36 eyes (92%) progressed after completion of chemotherapy: 15 of the 18 eyes (83.3%) with Reese-Ellsworth group I-III and 16 of 16 eyes (100%) with Reese-Ellsworth group IV-V tumors. Seventeen eyes (52%) had growth of a tumor, whereas 14 eyes (42%) had progressive vitreous seeding, and 2 eyes (6%) had new tumors develop. Fifteen eyes (42%) required external beam radiotherapy. Twenty-nine of 36 (80.5%) eyes were salvaged. The median follow-up after chemotherapy was 19 months (range, 3-42 months). CONCLUSIONS: Multiagent chemotherapy alone does not ensure a cure for multifocal intraocular retinoblastoma. Supplemental focal therapy is needed to control disease progression.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Retina/tratamiento farmacológico , Retinoblastoma/tratamiento farmacológico , Carboplatino/administración & dosificación , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Lactante , Masculino , Terapia Neoadyuvante , Estudios Prospectivos , Radioterapia Adyuvante , Desprendimiento de Retina/diagnóstico , Neoplasias de la Retina/diagnóstico , Neoplasias de la Retina/fisiopatología , Retinoblastoma/diagnóstico , Retinoblastoma/fisiopatología , Resultado del Tratamiento , Vincristina/administración & dosificación
10.
Med Pediatr Oncol ; 37(1): 30-5, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11466720

RESUMEN

BACKGROUND: Fewer than 10% of Ewing family of tumors (EFT) arise in the vertebrae. Little information is available regarding the clinical presentation and outcome of these tumors. PROCEDURE: We reviewed the clinical features, prognostic factors, and outcome of EFT of the spine identified at our institution between 1962 and 1999. RESULTS: Thirty-three (10%) of 344 patients with EFT had a primary vertebral tumor. There were 21 (64%) males. Median age at diagnosis was 13.3 years. Six patients had metastatic disease and 10 had tumors > or = 8 cm in diameter. Primary sites were sacral (13), thoracic (10), lumbar (8), and cervical (2) vertebrae. We found no association between the affected spinal region and outcome, although sacral tumors were associated with delayed diagnosis (4 vs. 2 months after onset of symptoms, P = 0.076). Pain (n = 32) and neurologic deficits (n = 31; 82% motor, 58% sensory, 42% bladder, 27% bowel) were the most common presenting features. All patients received combination chemotherapy and local radiotherapy. With a median follow up of 9.7 years, 5-year survival and event-free survival ( +/- SD) estimates were 48.1% (8.9%) and 35.6% (8.6%), respectively, comparable to those of other patients with EFT. Outcome was better for patients with tumor size < 8 cm (P = 0.008) or localized disease (P = 0.084). Treatment era and specific tumor site did not affect outcome. CONCLUSIONS: Outcomes are similar for primary EFT of the spine and primary EFT in other sites. Unlike others, we found that patients with sacral tumors did not fare worse than patients with tumors at other spinal sites.


Asunto(s)
Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/terapia , Neoplasias de la Columna Vertebral/diagnóstico , Neoplasias de la Columna Vertebral/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Niño , Preescolar , Diagnóstico Diferencial , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Lactante , Masculino , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Sarcoma de Ewing/secundario , Neoplasias de la Columna Vertebral/secundario , Resultado del Tratamiento
11.
J Clin Oncol ; 19(8): 2302-8, 2001 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-11304784

RESUMEN

PURPOSE: To examine two competing hypotheses relating to intellectual loss among children treated for medulloblastoma (MB): Children with MB either: (1) lose previously learned skills and information; or (2) acquire new skills and information but at a rate slower than expected compared with healthy same-age peers. PATIENTS AND METHODS: Forty-four pediatric MB patients were evaluated who were treated with postoperative radiation therapy (XRT) with or without chemotherapy. After completion of XRT, a total of 150 examinations were conducted by use of the child version of the Wechsler Intelligence SCALES: These evaluations provided a measure of intellectual functioning called the estimated full-scale intelligence quotient (FSIQ). Changes in patient performance corrected for age (scaled scores) as well as the uncorrected performance (raw scores) were analyzed. RESULTS: At the time of the most recent examination, the obtained mean estimated FSIQ of 83.57 was more than one SD below expected population norms. A significant decline in cognitive performance during the time since XRT was demonstrated, with a mean loss of 2.55 estimated FSIQ points per year (P =.0001). An analysis for the basis of the intelligence quotient (IQ) loss revealed that subtest raw score values increased significantly over time since XRT, but the rate of increase was less than normally expected, which resulted in decreased IQ scores. CONCLUSION: These results support the hypothesis that MB patients demonstrate a decline in IQ values because of an inability to acquire new skills and information at a rate comparable to their healthy same-age peers, as opposed to a loss of previously acquired information and skills.


Asunto(s)
Neoplasias Cerebelosas/psicología , Desarrollo Infantil , Trastornos del Conocimiento/etiología , Inteligencia , Meduloblastoma/psicología , Adolescente , Neoplasias Cerebelosas/complicaciones , Niño , Preescolar , Femenino , Humanos , Lactante , Aprendizaje , Estudios Longitudinales , Masculino , Meduloblastoma/complicaciones , Procesos Mentales
12.
Int J Radiat Oncol Biol Phys ; 49(1): 79-91, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11163500

RESUMEN

OBJECTIVE: To test a hypothesis that fractionated radiation therapy (RT) to less than 60 Gy is associated with a dose-related change in the spin-lattice relaxation time (T1) of normal brain tissue, and that such changes are detectable by quantitative MRI (qMRI). METHODS: Each of 21 patients received a qMRI examination before treatment, and at several time points during and after RT. A map of brain T1 was calculated and segmented into white matter and gray matter at each time point. The RT isodose contours were then superimposed upon the T1 map, and changes in brain tissue T1 were analyzed as a function of radiation dose and time following treatment. We used a mixed-model analysis to analyze the longitudinal trend in brain T1 from the start of RT to 1 year later. Predictive factors evaluated included patient age and clinical variables, such as RT dose, time since treatment, and the use of an imaging contrast agent. RESULTS: In white matter (WM), a dose level of greater than 20 Gy was associated with a dose-dependent decrease in T1 over time, which became significant about 3 months following treatment. In gray matter (GM), there was no significant change in T1 over time, as a function of RT doses < 60 Gy. However, GM in close proximity to the tumor had an inherently lower T1 before therapy. Neither use of a contrast agent nor a combination of chemotherapy plus steroids had a significant effect on brain T1. CONCLUSION: Results suggest that T1 mapping may be sensitive to radiation-related changes in human brain tissue T1. WM T1 appears to be unaffected by RT at doses less than approximately 20 Gy; GM T1 does not change at doses less than 60 Gy. However, tumor appears to have an effect upon adjacent GM, even before treatment. Conformal RT may offer a substantial benefit to the patient, by minimizing the volume of normal brain exposed to greater than 20 Gy.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Encéfalo/efectos de la radiación , Radioterapia Conformacional/métodos , Adolescente , Antineoplásicos/uso terapéutico , Encéfalo/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Niño , Preescolar , Irradiación Craneana/métodos , Fraccionamiento de la Dosis de Radiación , Relación Dosis-Respuesta en la Radiación , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Sensibilidad y Especificidad , Esteroides/uso terapéutico , Factores de Tiempo
13.
Ann Neurol ; 50(6): 787-95, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11761477

RESUMEN

We test a hypothesis that fractionated radiation therapy within a therapeutic dose range is associated with a dose-related change in normal brain, detectable by quantitative magnetic resonance imaging. A total of 33 patients were examined by quantitative magnetic resonance imaging to measure brain tissue spin-lattice relaxation time (T1) before treatment, and at various times during and after radiation therapy. A T1 map was generated at each time point, and radiation therapy isodose contours were superimposed on the corresponding segmented T1 map. Changes in white matter and gray matter T1 were analyzed as a function of radiation therapy dose and time since treatment, controlling for patient age and tumor site. In white matter, a dose level of more than 20 Gy was associated with a dose-dependent decrease in T1 over time, which became significant 6 months after treatment. There was no significant change in T1 of gray matter over time, at radiation therapy doses of less than 60 Gy. However, GM in close proximity to the tumor had a lower T1 before therapy. Our results represent the first radiation dose-response data derived from pediatric brain in vivo. These findings confirm that white matter is more vulnerable to radiation-induced change than is gray matter, and suggest that T1 mapping is sensitive to radiation-related changes over a broad dose range (20 to 60 Gy). Human white matter T1 is not sensitive to radiation therapy of less than 20 Gy, and gray matter T1 is unchanged over the dose range used to treat human brain tumor. The reduction of gray matter T1 near the tumor could result from compression of cortical parenchyma near the growing tumor mass, or from tumor cell invasion directly into the parenchyma. If brain T1 is a surrogate for radiation effect, reducing the volume of normal white matter receiving more than 20 Gy could be an important treatment planning goal.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Encéfalo/efectos de la radiación , Radiación Ionizante , Radioterapia Conformacional/efectos adversos , Adolescente , Encéfalo/patología , Niño , Preescolar , Relación Dosis-Respuesta en la Radiación , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Estudios Prospectivos , Dosificación Radioterapéutica
14.
J Pediatr Hematol Oncol ; 23(9): 568-71, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11902298

RESUMEN

PURPOSE: To determine the incidence, timing, and clinical significance of long-bone fractures in children with Ewing sarcoma family of tumors (ESFT). PATIENTS AND METHODS: We retrospectively reviewed 93 consecutive cases of ESFT of the long bones seen at a single institution over the course of a 37-year period. RESULTS: Fracture occurred in 14 (15%) of 93 patients with long-bone ESFT, most commonly in the femur. Approximately 30% of patients with tumors of the femur had fractures at some point in the course of their disease. The incidence of fracture was highest among patients with tumors of the proximal third of the femur (50%); these fractures were usually present at the time of initial diagnosis. Nine (64%) of the 14 fractures occurred after the start of radiotherapy, and three of these were associated with either local recurrence or second malignancy. CONCLUSIONS: Patients with femoral ESFT are at high-risk for fracture. If fractures occur after the completion of therapy, recurrence or second malignancy should be suspected.


Asunto(s)
Neoplasias Óseas/complicaciones , Fracturas Espontáneas/etiología , Sarcoma de Ewing/complicaciones , Adolescente , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/radioterapia , Niño , Preescolar , Terapia Combinada , Femenino , Fracturas del Fémur/epidemiología , Fracturas del Fémur/etiología , Fracturas Espontáneas/epidemiología , Histiocitoma Fibroso Benigno/complicaciones , Humanos , Masculino , Recurrencia Local de Neoplasia/complicaciones , Neoplasias Primarias Secundarias/complicaciones , Traumatismos por Radiación/epidemiología , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Estudios Retrospectivos , Sarcoma de Ewing/tratamiento farmacológico , Sarcoma de Ewing/radioterapia , Tibia , Factores de Tiempo , Resultado del Tratamiento , Soporte de Peso
15.
Int J Radiat Oncol Biol Phys ; 48(4): 1233-40, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11072183

RESUMEN

PURPOSE: To compare the accuracy of two immobilization techniques for pediatric brain tumor patients. METHODS AND MATERIALS: We analyzed data from 128 treatments involving 22 patients. Patients were immobilized with either a relocatable head frame (12 patients) or a vacuum bag (10 patients). Orthogonal portal films were used as verification images. Errors in patient positioning were measured by comparing verification images with digitally reconstructed radiographs generated by a three-dimensional treatment-planning system. RESULTS: With the head frame, systematic errors ranged from 1.4 mm to 2.1 mm; random errors, from 1.7 mm to 2.1 mm. With the vacuum bag, systematic errors ranged from 2.1 mm to 2.5 mm; random errors, from 2.0 mm to 2.6 mm. For the head frame, the mean length of the radial displacement was 4.4 mm; 90% of the total three-dimensional deviation was less than 6.8 mm. The corresponding values for the vacuum bag were 5.0 and 6.6 mm, respectively. CONCLUSIONS: The head frame and vacuum bag techniques limit the random and systematic errors in each of the three directions to within +/- 5 mm. We have used these results to determine the margin used to create the planning target volume for conformal radiation therapy.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Procesamiento de Imagen Asistido por Computador , Restricción Física/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Niño , Humanos , Fenómenos Físicos , Física , Radiografía , Restricción Física/instrumentación
16.
Magn Reson Imaging ; 18(7): 787-93, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11027871

RESUMEN

Medulloblastoma is the most common malignant brain tumor in children, and approximately seventy percent of average-risk patients will achieve long-term survival. Craniospinal irradiation (CSI), combined with chemotherapy and surgery, is currently the mainstay of treatment but places children who survive at risk for serious neurocognitive sequelae. These sequelae are intensified with a younger age at treatment, greater elapsed time following treatment, and an increased radiation dose. Many newer treatment approaches have attempted to address this problem by reducing the dose of the CSI component of radiation therapy while maintaining the current survival rates. This study evaluates longitudinal MR imaging during therapy to assess the impact of the two CSI doses (conventional [36 Gy] and reduced [23.4 Gy]) on normal appearing white matter volumes (NAWMV) evaluated in a single index slice. Twenty-six children and young adults at least three years of age enrolled on an institutional protocol for newly diagnosed, previously untreated primary medulloblastoma had at least four MR examinations over a minimum nine month period following CSI. These serial volumes were evaluated as a function of time since CSI in three analyses: 1) all subjects, 2) subjects stratified by age at CSI, and 3) subjects stratified by CSI dose. The first analysis demonstrated that medulloblastoma patients treated with CSI have a significant loss of NAWMV in contradistiction to normally expected maturation. Stratifying the patients by age at CSI found no significant differences in the rate of NAWMV loss. The final analysis stratified the patients by CSI dose and revealed that the rate of NAWMV loss was 23% slower in children receiving reduced-dose. Serial quantitative MR measures of NAWMV may provide a neuroanatomical substrate for assessing functional impact of CSI on normal brain function following treatment for medulloblastoma.


Asunto(s)
Neoplasias Cerebelosas/diagnóstico por imagen , Neoplasias Cerebelosas/diagnóstico , Irradiación Craneana/métodos , Imagen por Resonancia Magnética/métodos , Meduloblastoma/diagnóstico , Meduloblastoma/radioterapia , Vaina de Mielina/patología , Adolescente , Niño , Preescolar , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Masculino , Monitoreo Fisiológico/métodos , Pronóstico , Estudios Prospectivos , Dosis de Radiación , Radiografía , Sensibilidad y Especificidad , Resultado del Tratamiento
17.
Int J Radiat Oncol Biol Phys ; 47(5): 1267-71, 2000 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10889380

RESUMEN

PURPOSE: To retrospectively review the treatment and outcome of pediatric patients with desmoid tumor who received radiation therapy at a single institution. MATERIALS AND METHODS: Thirteen pediatric patients received radiation therapy for desmoid tumor at St. Jude Children's Research Hospital between 1962 and 1998. Only 2 of the patients reviewed received treatment prior to 1976. The median dose of external beam irradiation was 50 Gy. RESULTS: At the time of this report, 10 of 13 patients have had tumors that recurred after radiation therapy and 3 have died from their disease. One additional patient was harboring a recurrence, and 1 had not been followed long enough to suggest that the patient had achieved disease control. One patient remained locally controlled after radiation therapy with long-term follow-up (196 months). The median time to recurrence following radiation therapy was 19 months (range, 3-135 months). Eight of the 13 patients suffered substantial tumor and treatment-related morbidity. CONCLUSIONS: Desmoid tumors in pediatric patients are locally aggressive tumors that are likely to recur after radiation therapy. Alternatives to radiation therapy should be sought for the treatment of these tumors, and efforts should focus on low-morbidity therapies aimed at inhibiting the growth of these unique tumors.


Asunto(s)
Fibromatosis Agresiva/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Adolescente , Niño , Preescolar , Femenino , Fibromatosis Agresiva/complicaciones , Fibromatosis Agresiva/mortalidad , Estudios de Seguimiento , Humanos , Masculino , Recurrencia Local de Neoplasia/mortalidad , Radioterapia/efectos adversos , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
18.
Int J Radiat Oncol Biol Phys ; 47(2): 319-25, 2000 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10802355

RESUMEN

PURPOSE: Women with large breasts have marked dose inhomogeneity and often an inferior cosmetic outcome when treated with breast conservation compared to smaller-sized patients. We designed a prone breast board, which both minimizes breast separation and irradiated lung or heart volume. We report feasibility, cosmesis, and preliminary local control and survival for selected women with Stage 0-II breast cancer. MATERIALS AND METHODS: Fifty-six patients with clinical Stage 0-II breast cancer were treated with lumpectomy and breast irradiation utilizing a prototype prone breast board. A total of 59 breasts were treated. Indications for treatment in the prone position were large or pendulous breast size (n = 57), or a history of cardiopulmonary disease (n = 2). The median bra size was 41D (range, 34D-44EE). Cosmesis was evaluated on a 1-10 (worst-to-best) scale. RESULTS: Acute toxicity included skin erythema (80% of patients experienced Grade I or Grade II erythema), breast edema (72% of patients experienced mild edema), pruritus (20% of patients), and fatigue (20% of patients reported mild fatigue). One patient required a treatment break. The only late toxicity was related to long-term cosmesis. The mean overall cosmesis score for 53 patients was 9.37 (range, 8-10). Actuarial 3- and 5-year local control rates are 98%. Actuarial overall survival at 3 and 5 years are 98% and 94%. CONCLUSION: Our data indicate that treating selected women with prone breast radiotherapy is feasible and tolerated. The approach results in excellent cosmesis, and short-term outcome is comparable to traditional treatment techniques. This technique offers an innovative alternative to women who might not otherwise be considered candidates for breast conservation.


Asunto(s)
Neoplasias de la Mama/radioterapia , Posición Prona , Adulto , Anciano , Anciano de 80 o más Años , Mama/anatomía & histología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Estética , Estudios de Factibilidad , Femenino , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad , Instrumentos Quirúrgicos
19.
Pediatr Neurosurg ; 32(1): 30-6, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10765136

RESUMEN

Our institutional experience with pediatric spinal cord tumors includes 25 patients with the diagnosis of ependymoma (EP; n = 4), myxopapillary ependymoma (MPEP; n = 4), juvenile pilocytic astrocytoma (JPA; n = 5), nonpilocytic astrocytoma (WHO grade I or II, n = 6), and other nonastrocytic spinal cord tumors (n = 6) treated during the period 1974-1999. Nineteen patients required radiation therapy (RT). The median progression-free survival following RT was 65 months (range 1-206 months). Seven patients recurred at an average of 22 months. The EP patients recurred at an average of 8.5 months, while the patients with low-grade astrocytoma recurred at an average of 42 months. Including the 6 nonsurviving patients, the median overall survival was 96 months. Two EP patients died with a progression-free survival of 9 months. One patient with MPEP died of other causes at 7 months. The treatment of pediatric spinal cord tumors should be individualized based on the histologic type. Radical surgery is indicated for nonmyxopapillary EP and low-grade astrocytic tumors. The need for adjuvant therapy most often depends on the extent of resection as well as the tumor type. Patients with disseminated EP, MPEP, JPA and nonpilocytic astrocytoma may achieve long-term progression-free survival with craniospinal irradiation.


Asunto(s)
Astrocitoma/diagnóstico , Astrocitoma/cirugía , Ependimoma/diagnóstico , Ependimoma/cirugía , Glioma/diagnóstico , Glioma/cirugía , Recurrencia Local de Neoplasia/diagnóstico , Neoplasias de la Médula Espinal/diagnóstico , Neoplasias de la Médula Espinal/cirugía , Adolescente , Astrocitoma/mortalidad , Causas de Muerte , Quimioterapia Adyuvante , Niño , Preescolar , Supervivencia sin Enfermedad , Ependimoma/mortalidad , Femenino , Glioma/mortalidad , Humanos , Lactante , Masculino , Estadificación de Neoplasias , Radioterapia Adyuvante , Estudios Retrospectivos , Neoplasias de la Médula Espinal/mortalidad , Resultado del Tratamiento
20.
Int J Radiat Oncol Biol Phys ; 46(5): 1171-6, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10725628

RESUMEN

PURPOSE: To provide evidence that radiation therapy alone in the form of craniospinal irradiation (CSI) and a boost to the primary site of disease provides effective disease control and limited additional morbidity for patients with CNS germinoma. METHODS AND MATERIALS: Twelve patients with a median age of 12 years (range 9-16 years) with CNS germinoma were treated with CSI (median 25.6 Gy, range 23.4-32 Gy) and a boost to the primary site of disease (50.4 Gy, range 45-54 Gy) between January 1987 and June 1998. All patients were biopsied prior to radiation therapy and none received chemotherapy. No patients were lost to follow-up and the majority had long-term (> 45 month) pre- and postirradiation endocrine and psychology assessment. RESULTS: All 12 patients are alive and no failures have occurred with a median follow-up of 69 months (range 14-143 months). Preirradiation endocrine deficiencies were present in 6 of 6 suprasellar tumors and 1 of 6 pineal tumors; with follow-up there was no substantial difference between age and gender adjusted pre- and postirradiation stature and weight. With long-term follow-up, there were no significant differences between pre- and postirradiation full-scale, verbal, and performance IQ scores. CONCLUSIONS: This study confirms the ability of radiation therapy alone to achieve disease control with a high rate of success in pediatric patients and demonstrates that the treatment toxicity faced by these patients may be less than anticipated. Because these patients present with substantial preexisting morbidity at diagnosis and may be of an age where the potential for radiation-related side effects is relatively small, the superiority of treatment alternatives may be difficult to prove.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Irradiación Craneana , Germinoma/radioterapia , Adolescente , Estatura , Neoplasias Encefálicas/sangre , Niño , Sistema Endocrino/efectos de la radiación , Femenino , Estudios de Seguimiento , Germinoma/sangre , Humanos , Masculino , Pruebas Neuropsicológicas , Pinealoma/sangre , Pinealoma/radioterapia , Dosificación Radioterapéutica
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