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1.
J Appl Clin Med Phys ; 25(2): e14161, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37789572

RESUMEN

PURPOSE: To assess the feasibility of using the diaphragm as a surrogate for liver targets during MDTT. METHODS: Diaphragm as surrogate for markers: a dome-shaped phantom with implanted markers was fabricated and underwent dual-orthogonal fluoroscopy sequences on the Vero4DRT linac. Ten patients participated in an IRB-approved, feasibility study to assess the MDTT workflow. All images were analyzed using an in-house program to back-project the diaphragm/markers position to the isocenter plane. ExacTrac imager log files were analyzed. Diaphragm as tracking structure for MDTT: The phantom "diaphragm" was contoured as a markerless tracking structure (MTS) and exported to Vero4DRT/ExacTrac. A single field plan was delivered to the phantom film plane under static and MDTT conditions. In the patient study, the diaphragm tracking structure was contoured on CT breath-hold-exhale datasets. The MDTT workflow was applied until just prior to MV beam-on. RESULTS: Diaphragm as surrogate for markers: phantom data confirmed the in-house 3D back-projection program was functioning as intended. In patients, the diaphragm/marker relative positions had a mean ± RMS difference of 0.70 ± 0.89, 1.08 ± 1.26, and 0.96 ± 1.06 mm in ML, SI, and AP directions. Diaphragm as tracking structure for MDTT: Building a respiratory-correlation model using the diaphragm as surrogate for the implanted markers was successful in phantom/patients. During the tracking verification imaging step, the phantom mean ± SD difference between the image-detected and predicted "diaphragm" position was 0.52 ± 0.18 mm. The 2D film gamma (2%/2 mm) comparison (static to MDTT deliveries) was 98.2%. In patients, the mean difference between the image-detected and predicted diaphragm position was 2.02 ± 0.92 mm. The planning target margin contribution from MDTT diaphragm tracking is 2.2, 5.0, and 4.7 mm in the ML, SI, and AP directions. CONCLUSION: In phantom/patients, the diaphragm motion correlated well with markers' motion and could be used as a surrogate. MDTT workflows using the diaphragm as the MTS is feasible using the Vero4DRT linac and could replace the need for implanted markers for liver radiotherapy.


Asunto(s)
Diafragma , Neoplasias Pulmonares , Humanos , Diafragma/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Hígado/diagnóstico por imagen , Movimiento (Física) , Tórax , Fantasmas de Imagen
2.
J Appl Clin Med Phys ; 24(7): e13969, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36995913

RESUMEN

PURPOSE: To assess dynamic tumor tracking (DTT) target localization uncertainty for in-vivo marker-based stereotactic ablative radiotherapy (SABR) treatments of the liver using electronic-portal-imaging-device (EPID) images. The Planning Target Volume (PTV) margin contribution for DTT is estimated. METHODS: Phantom and patient EPID images were acquired during non-coplanar 3DCRT-DTT delivered on a Vero4DRT linac. A chain-code algorithm was applied to detect Multileaf Collimator (MLC)-defined radiation field edges. Gold-seed markers were detected using a connected neighbor algorithm. For each EPID image, the absolute differences between the measured center-of-mass (COM) of the markers relative to the aperture-center (Tracking Error, (ET )) was reported in pan, tilt, and 2D-vector directions at the isocenter-plane. PHANTOM STUDY: An acrylic cube phantom implanted with gold-seed markers was irradiated with non-coplanar 3DCRT-DTT beams and EPID images collected. Patient Study: Eight liver SABR patients were treated with non-coplanar 3DCRT-DTT beams. All patients had three to four implanted gold-markers. In-vivo EPID images were analyzed. RESULTS: Phantom Study: On the 125 EPID images collected, 100% of the markers were identified. The average ± SD of ET were 0.24 ± 0.21, 0.47 ± 0.38, and 0.58 ± 0.37 mm in pan, tilt and 2D directions, respectively. Patient Study: Of the 1430 EPID patient images acquired, 78% had detectable markers. Over all patients, the average ± SD of ET was 0.33 ± 0.41 mm in pan, 0.63 ± 0.75 mm in tilt and 0.77 ± 0.80 mm in 2D directions The random 2D-error, σ, for all patients was 0.79 mm and the systematic 2D-error, Σ, was 0.20 mm. Using the Van Herk margin formula 1.1 mm planning target margin can represent the marker based DTT uncertainty. CONCLUSIONS: Marker-based DTT uncertainty can be evaluated in-vivo on a field-by-field basis using EPID images. This information can contribute to PTV margin calculations for DTT.


Asunto(s)
Neoplasias , Radiocirugia , Radioterapia Conformacional , Humanos , Radiometría/métodos , Radioterapia Conformacional/métodos , Fantasmas de Imagen , Hígado/diagnóstico por imagen , Hígado/cirugía , Planificación de la Radioterapia Asistida por Computador/métodos , Dosificación Radioterapéutica
3.
Clin Colorectal Cancer ; 22(1): 120-128, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36526537

RESUMEN

INTRODUCTION: Stereotactic Ablative Radiation Therapy (SABR) is a therapeutic option for patients with inoperable oligometastatic colorectal carcinoma (CRC). Given the scarcity of prospective data on outcomes of SABR for metastatic CRC, this study aims to review SABR outcomes and determine predictive factors of local control (LC) and survival in patients with liver metastases from CRC. MATERIALS AND METHODS: A retrospective review of SABR for CRC liver metastases between 2011 and 2019 was undertaken. Endpoints included LC, overall survival (OS), progression-free survival (PFS) and time to restarting systemic therapy. Univariate (UVA) and multivariable analyses (MVA) were performed to identify predictive factors. RESULTS: Forty-eight patients were identified. The total number of tumors treated was 58. Median follow-up was 26.6 months. LC at 1, 2 and 3 years was 92.7%, 80.0%, and 61.2% respectively. Median time to local failure was 40.0 months (95% CI 31.8-76.1 months). Median OS was 31.9 months (95% CI 20.6-40.0 months). OS at 1, 2, and 3 years was 79.2%, 61.7%, and 44.9% respectively. Thirty-three patients (69%) restarted systemic therapy after completion of SABR. Median time to restarting chemotherapy was 11.0 months (95% CI 7.1-17.6 months). Systemic therapy free survival at 1, 2, and 3 years was 45.7%, 29.6%, and 22.6% respectively. On MVA, inferior LC was influenced by GTV volume ≥40 cm3 (HR: 3.805, 95% CI 1.376-10.521, P = .01) and PTV D100% BED <100 Gy10 (HR 2.971, 95% CI 1.110-7.953; P = .03). Inferior OS was associated with PTV volume ≥200 cm3 (HR 5.679, 95% CI 2.339-13.755; P < .001). CONCLUSION: SABR is an effective therapeutic option for selected patients with CRC liver metastases providing acceptable LC within the first 2 years. In many cases, it provides meaningful chemotherapy-free intervals. Higher biological effective doses are required to enhance LC.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Radiocirugia , Humanos , Estudios Prospectivos , Radiocirugia/efectos adversos , Supervivencia sin Progresión , Estudios Retrospectivos , Neoplasias Hepáticas/radioterapia , Neoplasias Colorrectales/patología
4.
World Neurosurg ; 161: e748-e756, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35240308

RESUMEN

OBJECTIVE: We sought to evaluate overall survival (OS) and local recurrence (LR) in patients with grade 2 meningiomas treated with adjuvant radiotherapy compared to surgery alone at time of diagnosis. METHODS: All patients at the authors' institution between 2007 and 2020 were retrospectively reviewed. OS, LR, and treatment toxicities were assessed. Sensitivity analyses were performed for patients with initial gross total resection (GTR) and subtotal resection (STR). Kaplan-Meier analyses and log-rank test for significance were used to compare surgery alone and adjuvant radiotherapy groups. RESULTS: We included 189 patients with mean age 57.4 ± 14.6 years. Patients were 64% female, and median follow-up was 64 (interquartile range: 20-96) months. At initial treatment, 21 patients received adjuvant radiotherapy and 168 received surgery alone. There was no significant difference for OS (hazard ratio = 1.3 [95% confidence interval 0.4-4.5], P = 0.92) overall or when limited to GTR (P = 0.38) or STR (P = 0.85). There was no significant difference in LR overall (P = 0.75) or when restricted to GTR (P = 0.77) or STR (P = 0.20). No patient had radiotherapy stopped or altered because of side effects; however, 71.4% reported tolerable side effects during the treatment period and 14.3% reported chronic side effects persisting longer than 12 months post treatment. CONCLUSIONS: In a large retrospective cohort, we found no survival or local recurrence benefit to adjuvant radiotherapy in treatment of grade 2 meningiomas. Sensitivity analysis limited to initial GTR and STR also failed to demonstrate any OS or LR benefit with adjuvant radiotherapy. In our experience, there is limited utility to upfront adjuvant radiotherapy following initial surgical resection in the treatment of grade 2 meningiomas.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Adulto , Anciano , Femenino , Humanos , Masculino , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirugía , Meningioma/radioterapia , Meningioma/cirugía , Persona de Mediana Edad , Radioterapia Adyuvante , Estudios Retrospectivos , Centros de Atención Terciaria
5.
J Appl Clin Med Phys ; 22(6): 16-25, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34042251

RESUMEN

PURPOSE: In this study we present a novel method for re-calculating a treatment plan on different respiratory phases by accurately modeling the panning and tilting beam motion during DTT (the "rotation method"). This method is used to re-calculate the dose distribution of a plan on multiple breathing phases to accurately assess the dosimetry. METHODS: sIMRT plans were optimized on a breath hold computed tomography (CT) image taken at exhale (BHexhale ) for 10 previous liver stereotactic ablative radiotherapy patients. Our method was used to re-calculate the plan on the inhale (0%) and exhale (50%) phases of the four-dimensional CT (4DCT) image set. The dose distributions were deformed to the BHexhale CT and summed together with proper weighting calculated from the patient's breathing trace. Subsequently, the plan was re-calculated on all ten phases using our method and the dose distributions were deformed to the BHexhale CT and accumulated together. The maximum dose for certain organs at risk (OARs) was compared between calculating on two phases and all ten phases. RESULTS: In total, 26 OARs were examined from 10 patients. When the dose was calculated on the inhale and exhale phases six OARs exceeded their dose limit, and when all 10 phases were used five OARs exceeded their limit. CONCLUSION: Dynamic tumor tracking plans optimized for a single respiratory phase leave an OAR vulnerable to exceeding its dose constraint during other respiratory phases. The rotation method accurately models the beam's geometry. Using deformable image registration to accumulate dose from all 10 breathing phases provides the most accurate results, however it is a time consuming procedure. Accumulating the dose from two extreme breathing phases (exhale and inhale) and weighting them properly provides accurate results while requiring less time. This approach should be used to confirm the safety of a DTT treatment plan prior to delivery.


Asunto(s)
Neoplasias Pulmonares , Neoplasias , Tomografía Computarizada Cuatridimensional , Humanos , Aceleradores de Partículas , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Respiración
6.
Radiat Oncol ; 15(1): 271, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33239056

RESUMEN

PURPOSE: To investigate predictors of cognitive decline after whole brain radiotherapy (WBRT) for brain metastases. METHODS: A secondary analysis of a phase 2 clinical trial was conducted in patients who received stereotactic radiosurgery for 1-10 brain metastases and WBRT (NCT01046123). The Montreal Cognitive Assessment (MoCA) was performed at baseline and every 3 months after WBRT. Baseline T2-weighted fluid attenuation inversion recovery magnetic resonance imaging was independently assessed by two neuroradiologists for the presence of white matter hyperintensities (WMH) using the Fazekas visual rating scale. WMH were also manually segmented for volumetric analysis. Univariable and multivariable logistic regression were used to test the association between baseline variables and MoCA score decline. RESULTS: Forty-six patients survived ≥ 3 months after treatment. Age (OR 1.12 (1.04-1.21), p < 0.01), baseline WMH volume (OR 1.20, 95% CI 1.06-1.52, p = 0.02) and baseline Fazekas score ≥ 3/6 (OR 6.4, 95% CI 1.7-24.7, p < 0.01) were predictive of MoCA score decline. In multivariable analysis, age was the only significant predictor of MoCA decline. However, all three patients with pre-treatment leukoencephalopathy (Fazekas score = 6/6) had notable adverse outcomes due to cognitive impairment: one required full-time home nursing support and two were institutionalized. CONCLUSION: A greater decline in cognition after WBRT was observed in older patients and patients with a higher baseline WMH burden. Although this study is small and hypothesis-generating, we propose that radiation oncologists should exercise caution in prescribing WBRT if leukoencephalopathy is present on pre-treatment imaging. TRIAL REGISTRATION: clinicaltrials.gov identifier NCT01046123. First posted January 11, 2010. https://clinicaltrials.gov/ct2/show/NCT01046123.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Disfunción Cognitiva/etiología , Irradiación Craneana/efectos adversos , Leucoencefalopatías/complicaciones , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Radiocirugia
7.
World Neurosurg ; 120: e511-e516, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30149161

RESUMEN

BACKGROUND: Glioblastoma (GBM) is the most common malignant primary brain cancer in adults. Recent efforts have elucidated genetic features of tumor cells and thus enhanced our knowledge of GBM pathophysiology. The most recent clinical trials report median overall survival between 14 and 20 months. However, population level outcomes are quite variable and there is a paucity of such data within the literature. METHODS: Three hundred seventy-two patients with GBM were diagnosed in the Canadian province of British Columbia between January 2013 and January 2015 and 278 patients had surgery. Of these, 268 had surgery in British Columbia and we have performed a retrospective review of their survival outcomes. RESULTS: Our results indicate a median age of 61.8 years at time of diagnosis, with a slight preponderance of male patients. The median overall survival was 10 months for patients in our cohort. As expected, patients older than the age of 65 and those with worse initial Karnofsky Performance Status scores had a poorer prognosis. Moreover, we have found extent of resection, treatment strategies, and treatment location affect overall survival. CONCLUSIONS: The present study highlights factors that affect patient survival after surgery in British Columbia. Our data are gathered within a single-payer, high-resource setting which removes possible confounders in outcome analysis. We find persistent differences in overall survival when compared with clinical trials and the Surveillance, Epidemiology, and End Results database. Further efforts should ensure access to the gold standard of care. All neuro-oncology centers should analyze the real-world outcomes of their local glioblastoma treatment strategies. Knowledge of the variance from expected and comparative results are fundamental for appropriate patient care.


Asunto(s)
Neoplasias Encefálicas/cirugía , Glioblastoma/cirugía , Disparidades en Atención de Salud/estadística & datos numéricos , Factores de Edad , Anciano , Neoplasias Encefálicas/mortalidad , Colombia Británica/epidemiología , Estudios de Cohortes , Femenino , Glioblastoma/mortalidad , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
8.
Br J Radiol ; 91(1085): 20170118, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29334232

RESUMEN

Surgical resection, when feasible, is the standard of care for hepatocellular carcinoma. However, many tumours are not resectable at the time of diagnosis. Recently, stereotactic body radiation therapy (SBRT) has emerged as a non-invasive local therapy for both non-resectable primary hepatic malignancies as well as hepatic metastases. Knowledge of the expected hepatic parenchymal appearance post treatment, as well as potential pitfalls and complications, is essential for accurate evaluation of treatment response. This pictorial review provides a fundamental description of the SBRT technique, outlines the expected cross-sectional imaging appearances of tumour response, and highlights potential pitfalls in interpretation. The expected liver parenchymal changes post-SBRT are also reviewed, along with some common radiation-induced complications.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/radioterapia , Diagnóstico por Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Radiocirugia/métodos , Humanos , Hígado/diagnóstico por imagen , Hígado/efectos de la radiación , Resultado del Tratamiento
9.
Ophthalmic Plast Reconstr Surg ; 34(3): 217-221, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28422769

RESUMEN

PURPOSE: To review the outcomes of patients with optic nerve sheath meningiomas (ONSM) treated with fractionated stereotactic radiotherapy. METHODS: Patient characteristics, treatment, and outcomes were analyzed for all patients with primary and secondary ONSM treated from 2001 to 2012. Clinically significant visual acuity change was defined as a 2-line change on the Snellen eye chart from pre-fractionated stereotactic radiotherapy. RESULTS: Forty-one patients were treated: 23 patients with primary ONSM and 18 patients with secondary ONSM. The median age at diagnosis was 56 years. The median visual follow up was 3.8 years and the median radiologic follow up was 4.4 years. At diagnosis, 36% had normal vision (20/20-20/40), 10% had mild impairment (<20/40-20/60), 20% had moderate visual impairment (<20/60-20/200), 27% had severe impairment (<20/200), and 7% had no light perception. Common acute side effects were headache (32%) and nausea (15%); 15% of patients required corticosteroids during stereotactic radiotherapy. Chronic toxicities included retinopathy (7%), pituitary dysfunction (13%), chronic ocular pain (5%), and cataracts (2%). Visual acuity was stable in 65%, improved in 27%, and decreased in 8% of patients. Visual fields were stable in 70%, improved in 21%, and reduced in 9%. Actuarial 5-year local control rates were 100% for primary ONSM and 88% for secondary ONSM. Actuarial 5-year visual preservation rates were 100% for primary ONSM and 86% for secondary ONSM. CONCLUSIONS: Fractionated stereotactic radiotherapy for primary and secondary ONSM was well tolerated and provides excellent local control and visual preservation. Longer follow up is required to determine the risk of late ocular and pituitary sequelae.


Asunto(s)
Meningioma/radioterapia , Neoplasias del Nervio Óptico/radioterapia , Radiocirugia/métodos , Adulto , Anciano , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Agudeza Visual , Campos Visuales , Adulto Joven
10.
Int J Radiat Oncol Biol Phys ; 100(2): 443-451, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29066124

RESUMEN

PURPOSE: To examine long-term local control of vestibular schwannoma and side effects in patients treated with stereotactic radiosurgery (SRS) and fractionated stereotactic radiation therapy (SRT) in British Columbia. METHODS AND MATERIALS: From August 1998 to May 2009, 207 patients were treated with radiation therapy (RT) at British Columbia Cancer Agency. 136 (66%) received SRS, and 71 (34%) received SRT. Dose prescriptions were 50 Gy/25 fractions for SRT and 12 Gy/1 fraction for SRS. Our multidisciplinary provincial neuro-stereotactic conference recommended SRT for tumors >3 cm and for patients with serviceable hearing (Gardner-Robertson classes I and II). RESULTS: Median follow-up was 7.7 years to the last MRI and 6.4 years to the last clinical assessment. Local control for SRS versus SRT was 94% versus 87% at 5 years and 90% versus 85% at 10 years (P=.2). Five- and 10-year actuarial rates of RT-induced trigeminal nerve dysfunction were 25% and 25% after SRS, compared with 7% and 12% after SRT (P=.01). Five- and 10-year actuarial rates of RT-induced facial nerve dysfunction were 15% and 15% after SRS, versus 13% and 15% after SRT (P=.93). In the 49 patients with serviceable hearing at baseline who were treated with SRT, hearing preservation was 55% at 3 years, 37% at 5 years, and 29% at 7 years. In multivariable analysis, better pretreatment ipsilateral pure tone average was significantly associated with hearing preservation (hazard ratio 1.03; 95% confidence interval 1.00-1.07; P=.04). CONCLUSIONS: Both SRS and SRT provided excellent long-term local control of vestibular schwannoma. Stereotactic radiosurgery was associated with higher rates of trigeminal nerve dysfunction. Even with a fractionated course, hearing preservation declined steadily with long-term audiometric follow-up.


Asunto(s)
Fraccionamiento de la Dosis de Radiación , Neuroma Acústico/radioterapia , Radiocirugia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Audición/efectos de la radiación , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Radiocirugia/efectos adversos , Enfermedades del Nervio Trigémino/etiología , Adulto Joven
11.
Future Oncol ; 13(16): 1437-1448, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28685607

RESUMEN

Primary liver cancer, mainly hepatocellular carcinoma, is one of the most common malignancies worldwide. Surgical management, either resection or transplantation, is considered definitive treatment, however, less than 20% of patients are ultimately candidates. Thermal ablation modalities such as radiofrequency ablation and microwave ablation have evolved such that these modalities have been applied with curative intent. Moreover, thermal ablation has demonstrated efficacy in treating early-stage tumors and can be offered as first-line treatment in patients with uncomplicated disease. Attributing to refinements in technology and techniques, recent studies evaluating stereotactic ablative body radiotherapy have shown promising results, while irreversible electroporation, an emerging modality, may further expand the role of ablative therapy in treating potentially resectable hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/terapia , Ablación por Catéter , Neoplasias Hepáticas/terapia , Microondas/uso terapéutico , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/patología , Radiocirugia , Resultado del Tratamiento
12.
Dis Colon Rectum ; 59(3): 173-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26855390

RESUMEN

BACKGROUND: Total mesorectal excision has long been the standard of care for patients with rectal cancer. However, in select patients, local excision is an appropriate alternative option. The role of adjuvant radiation therapy in patients treated with local excision is controversial and evidence is lacking. OBJECTIVE: The purpose of this study was to report oncological outcomes of patients with rectal cancer treated with local excision and adjuvant radiation. DESIGN: This study was a retrospective chart review. SETTINGS: The study was conducted at the BC Cancer Agency, a tertiary referral hospital. PATIENTS: A total of 93 patients with node-negative rectal cancer treated with local excision and adjuvant radiotherapy between 2001 and 2010 were included in the study. MAIN OUTCOME MEASURES: Patient and tumor characteristics are reported. Five-year local control, progression-free survival, and overall survival were analyzed using Kaplan-Meier methods. RESULTS: Five-year overall survival, local control, and progression-free survival for patients treated with local excision and adjuvant radiotherapy were 78.5%, 86.1%, and 83.8%. In T1 disease, local control was 92.5%. LIMITATIONS: Referral bias, selection bias, lack of uniform surveillance, and retrospective analysis are the study limitations. CONCLUSIONS: Local excision with adjuvant radiotherapy provides a good level of local control in T1 disease and remains a good treatment option for patients who are either medically not suitable for a more radical surgical approach or who refuse this procedure. Local excision and radiotherapy should not be advocated in T2/T3 disease; however, it can provide a good alternative in those patients who are not fit enough for a more radical operation.


Asunto(s)
Adenocarcinoma/cirugía , Colectomía/métodos , Cirugía Endoscópica por Orificios Naturales/métodos , Estadificación de Neoplasias , Neoplasias del Recto/cirugía , Adenocarcinoma/mortalidad , Adenocarcinoma/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Colombia Británica/epidemiología , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante , Neoplasias del Recto/mortalidad , Neoplasias del Recto/radioterapia , Estudios Retrospectivos , Tasa de Supervivencia/tendencias
13.
Int J Radiat Oncol Biol Phys ; 94(2): 312-21, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26678660

RESUMEN

PURPOSE: Interest is growing in treating multiple brain metastases with radiosurgery. We report on the effectiveness and tolerability of volumetric radiosurgery (VRS). METHODS AND MATERIALS: We enrolled patients with a ≥6-month estimated life expectancy and 1 to 10 brain metastases with a diameter of ≤3 cm at 5 cancer centers. Volumetric radiosurgery was delivered in 5 fractions with 98% target coverage, prescribed as 95% of 50 Gy (47.5 Gy in 5 fractions) to the metastases with no margin and 95% of 40 Gy (38 Gy in 5 fractions) to their 2-mm planning target volumes, concurrent with 20 Gy to the whole brain planning target volume. The treatment was delivered with daily image guidance using conventional linear accelerators and volumetric modulated arc therapy. A magnetic resonance imaging scan was obtained every 3 months. The primary endpoint was the 3-month objective response in the brain according to the Response Evaluation Criteria in Solid Tumors, version 1.1. The principal secondary endpoint was 1-year actuarial control of treated metastases. Toxicities were graded using the Common Terminology Criteria for Adverse Events, version 4.0. The present study is registered with ClinicalTrials.gov (clinicaltrials.gov identifier NCT01046123). RESULTS: From July 2010 to May 2013, 60 patients underwent VRS with 47.5 Gy in 5 fractions for 12 metastases in the thalamus and basal ganglia (deep metastases) and 207 non-deep metastases. The median follow-up period was 30.5 months, and the median survival was 10.1 months. For the 43 patients assessable at 3 months, the objective response in the brain was 56%. The treated metastases were controlled in 88% of patients at 1 year and 84% at 3 years. Overall survival did not differ for patients with 4 to 10 versus 1 to 3 metastases (hazard ratio 1.18, P=.6). The crude incidence of severe radionecrosis (grade 3-5) was 25% (3 of 12) per deep metastasis, 1.9% (4 of 219) per non-deep metastasis, and 10% (6 of 60) per patient. CONCLUSIONS: For non-deep brain metastases, 47.5 Gy in 5 fractions was tolerable. Volumetric radiosurgery was effective for long-term control of treated brain metastases.


Asunto(s)
Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Radiocirugia/métodos , Radioterapia Guiada por Imagen/métodos , Radioterapia de Intensidad Modulada/métodos , Adulto , Anciano , Anciano de 80 o más Años , Ganglios Basales , Neoplasias Encefálicas/mortalidad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tálamo , Factores de Tiempo
14.
Can J Neurol Sci ; 42(5): 333-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26062572

RESUMEN

BACKGROUND: To examine stereotactic radiosurgery (SRS) following whole brain radiotherapy for metastases in eloquent, central brain locations: brainstem, thalamus, and basal ganglia. METHODS: We conducted a retrospective review of patients with metastases in eloquent, central brain locations who were treated with SRS between January 2000 and April 2012. All patients had whole brain radiotherapy. Patients eligible for SRS had one to three brain metastases, metastasis size ≤4 cm, and Karnofsky performance status ≥70. Local progression-free survival and overall survival were calculated using the Kaplan-Meier method. RESULTS: For 24 patients, the median age was 50 years (range, 36-73). Metastases by location were: 11 brainstem, 9 thalamus, and 5 basal ganglia. The median metastasis size was 15 mm (range, 2-33) and the median SRS dose prescription was 15 Gy (range, 12-24). The median local progression-free survival was 13.7 months and median overall survival was 16.4 months. Compared with a cohort of 188 patients with noneloquent brain metastases receiving a median dose of 24 Gy, overall survival of 10.8 months was not significantly different (p=0.16). The only symptomatic complication was grade 2 headache in 8.3%. Asymptomatic adverse radiologic events were radionecrosis in two (8.3%), peritumoural edema in four (16.7%), and hemorrhage in one patient (4.2%). CONCLUSIONS: Lower SRS marginal doses do not appear to compromise survival in patients with eloquently located brain metastases compared with higher doses for other brain metastases, with minimal symptomatic complications.


Asunto(s)
Neoplasias Encefálicas/cirugía , Encéfalo/cirugía , Metástasis de la Neoplasia/terapia , Radiocirugia/métodos , Encéfalo/patología , Neoplasias Encefálicas/diagnóstico , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Estado de Ejecución de Karnofsky , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X
15.
Ocul Oncol Pathol ; 2(1): 29-35, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27171272

RESUMEN

BACKGROUND AND PURPOSE: To report outcomes and toxicity after proton beam radiotherapy for non-peripapillary choroidal and ciliary body melanoma considered unsuitable for other eye-sparing therapies. MATERIALS AND METHODS: An existing database of 77 patients with non-peripapillary tumors treated at TRIUMF, Canada, including patient, tumor, and treatment characteristics, was updated with ocular complications and follow-up status from chart reviews. RESULTS: Most of the patients had large tumors: 61% were T3/T4 tumors (AJCC classification), while 48% were large by the Collaborative Ocular Melanoma Study classification. The median thickness was 7.1 mm, and the ciliary body was involved in 35%. After 5 and 10 years, the actuarial ocular tumor control rate was 85 and 85%, metastasis-free survival was 72 and 57%, overall survival was 77 and 63%, the enucleation rate was 22 and 22%, and complete blindness was found in 38 and 38%, respectively. On univariate analysis, patients with ciliary body involvement had significantly worse metastasis-free survival and overall survival rates compared to patients without ciliary body involvement (p < 0.001). CONCLUSIONS: Proton therapy for large anteriorly located tumors resulted in acceptable ocular tumor control and survival rates. The risk of blindness and severe toxicity requiring enucleation was low, and a substantial proportion of patients maintained useful vision.

16.
Brain Behav Immun ; 41: 191-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25242587

RESUMEN

Chronic stress is associated with morbidity and mortality from numerous conditions, many of whose pathogenesis involves persistent inflammation. Here, we examine how chronic stress influences signaling pathways that regulate inflammation in monocytes. The sample consisted of 33 adults caring for a family member with glioblastoma and 47 controls whose lives were free of major stressors. The subjects were assessed four times over eight months. Relative to controls, caregivers' monocytes showed increased expression of genes bearing response elements for nuclear-factor kappa B, a key pro-inflammatory transcription factor. Simultaneously, caregivers showed reduced expression of genes with response elements for the glucocorticoid receptor, a transcription factor that conveys cortisol's anti-inflammatory signals to monocytes. Transcript origin analyses revealed that CD14+/CD16- cells, a population of immature monocytes, were the predominate source of inflammatory gene expression among caregivers. We considered hormonal, molecular, and functional explanations for caregivers' decreased glucocorticoid-mediated transcription. Across twelve days, the groups displayed similar diurnal cortisol profiles, suggesting that differential adrenocortical activity was not involved. Moreover, the groups' monocytes expressed similar amounts of glucocorticoid receptor protein, suggesting that differential receptor availability was not involved. In ex vivo studies, subjects' monocytes were stimulated with lipopolysaccharide, and caregivers showed greater production of the inflammatory cytokine interleukin-6 relative to controls. However, no group differences in functional glucocorticoid sensitivity were apparent; hydrocortisone was equally effective at inhibiting cytokine production in caregivers and controls. These findings may help shed light on the mechanisms through which caregiving increases vulnerability to inflammation-related diseases.


Asunto(s)
Cuidadores , Hidrocortisona/metabolismo , Inflamación/inmunología , Monocitos/inmunología , Receptores de Glucocorticoides/fisiología , Transducción de Señal/inmunología , Estrés Psicológico/inmunología , Adulto , Biomarcadores/metabolismo , Neoplasias Encefálicas , Proteína C-Reactiva/análisis , Cuidadores/psicología , Células Cultivadas , Enfermedad Crónica , Femenino , Perfilación de la Expresión Génica , Glioblastoma , Humanos , Hidrocortisona/farmacología , Inflamación/genética , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Lipopolisacáridos/farmacología , Masculino , Persona de Mediana Edad , Monocitos/fisiología , Saliva/química , Estrés Psicológico/sangre , Estrés Psicológico/genética , Transcripción Genética
17.
Am J Ophthalmol ; 157(6): 1299-305, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24582992

RESUMEN

PURPOSE: To compare the risk of developing compressive optic neuropathy in patients with active thyroid eye disease (TED) treated with corticosteroids with or without orbital radiotherapy. DESIGN: Retrospective single-center case-control study. METHODS: The clinical charts of 351 patients with active TED who received corticosteroids with or without orbital radiotherapy between 1999 and 2010 were reviewed. Patients with compressive optic neuropathy at the time of presentation were excluded. Group 1 received corticosteroids only and Group 2 received corticosteroids as well as orbital radiotherapy. The primary outcome measure was the development of compressive optic neuropathy. Secondary outcome measures were changes in other parameters indicating the activity of TED, including soft tissue inflammation, diplopia, ocular motility restriction, and appearance. RESULTS: There were 144 cases in Group 1 and 105 in Group 2. Both groups were matched for age, sex, and stability of thyroid function. The 2 groups differed only in the modality of treatment for active TED. The main indication for treatment in both groups was soft tissue inflammation. Corticosteroids were initiated an average of 2.6 months following symptom onset in Group 1 and 2.5 months in Group 2. Group 2 received orbital radiotherapy on average 4.2 months following the initiation of corticosteroid therapy and 8% (9/105) were intolerant to corticosteroids. At an average of 3.2 years follow-up, compressive optic neuropathy had developed in 17% (25/144) of Group 1 and 0% of Group 2 (P < .0001), on average 5.5 months following the initiation of corticosteroid therapy. Although both groups experienced a significant reduction in periocular inflammation, the radiotherapy-treated group demonstrated a significantly greater improvement in ocular motility. CONCLUSION: The rate of compressive optic neuropathy was significantly lower and improvement in ocular motility greater in patients receiving orbital radiotherapy in addition to corticosteroids. Patients with active TED appear to have an effective and sustained response to orbital radiotherapy combined with corticosteroids that is protective against disease progression and the development of compressive optic neuropathy.


Asunto(s)
Glucocorticoides/uso terapéutico , Oftalmopatía de Graves/tratamiento farmacológico , Oftalmopatía de Graves/radioterapia , Enfermedades del Nervio Óptico/prevención & control , Enfermedades Orbitales/tratamiento farmacológico , Enfermedades Orbitales/radioterapia , Terapia de Protones , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Terapia Combinada , Diplopía/fisiopatología , Femenino , Oftalmopatía de Graves/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Motilidad Ocular/fisiopatología , Enfermedades Orbitales/fisiopatología , Estudios Retrospectivos , Adulto Joven
18.
Can J Neurol Sci ; 41(1): 74-81, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24384341

RESUMEN

OBJECTIVE: To report an unusual case of malignant degeneration in a ganglioneuroma of the jugular foramen post stereotactic radiosurgery as well as to systematically review the pertinent literature involving radiosurgery associated malignancies. BACKGROUND: Ganglioneuromas are uncommon lesions of the peripheral nervous system and infrequently reported in the head and neck region. There have been no previously described cases of ganglioneuromas occurring in the jugular foramen. Malignant degeneration of these lesions is rarely described, especially in the context of radiosurgery. Radiosurgery associated malignancies overall are exceptionally rare and only a limited number of cases have been reported. RESULTS/CONCLUSIONS: We describe a case of a ganglioneuroma occurring in the jugular foramen and mimicking the appearance of a jugular foramen schwannoma. This lesion underwent stereotactic radiosurgery and developed a delayed degeneration into a malignant nerve sheath tumor. The occurrence of ganglioneuroma in this region has not been previously described and presumed malignant degeneration is even rarer. This case highlights a previously understated risk associated with stereotactic radiation treatments. To date, 33 previous cases of stereotactic radiosurgery associated malignancies have been reported. We review the pertinent details of these cases. We caution that as follow up periods and awareness increases, reports such as this may become increasingly common.Tumeurs malignes des gaines nerveuses périphériques après la radiochirurgie : à propos d'un cas et revue de littérature.


Asunto(s)
Ganglioneuroma/diagnóstico , Ganglioneuroma/etiología , Neurilemoma/diagnóstico , Neurilemoma/etiología , Radiocirugia/efectos adversos , Informe de Investigación , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
19.
Int J Radiat Oncol Biol Phys ; 87(5): 1100-6, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24161427

RESUMEN

PURPOSE: The objective of this study was to compare recurrent tumor locations after radiation therapy with pretreatment delineations of high-grade gliomas from magnetic resonance imaging (MRI) and 3,4-dihydroxy-6-[(18)F]fluoro-L-phenylalanine ((18)F-FDOPA) positron emission tomography (PET) using contours delineated by multiple observers. METHODS AND MATERIALS: Nineteen patients with newly diagnosed high-grade gliomas underwent computed tomography (CT), gadolinium contrast-enhanced MRI, and (18)F-FDOPA PET/CT. The image sets (CT, MRI, and PET/CT) were registered, and 5 observers contoured gross tumor volumes (GTVs) using MRI and PET. Consensus contours were obtained by simultaneous truth and performance level estimation (STAPLE). Interobserver variability was quantified by the percentage of volume overlap. Recurrent tumor locations after radiation therapy were contoured by each observer using CT or MRI. Consensus recurrence contours were obtained with STAPLE. RESULTS: The mean interobserver volume overlap for PET GTVs (42% ± 22%) and MRI GTVs (41% ± 22%) was not significantly different (P=.67). The mean consensus volume was significantly larger for PET GTVs (58.6 ± 52.4 cm(3)) than for MRI GTVs (30.8 ± 26.0 cm(3), P=.003). More than 95% of the consensus recurrence volume was within the 95% isodose surface for 11 of 12 (92%) cases with recurrent tumor imaging. Ten (91%) of these cases extended beyond the PET GTV, and 9 (82%) were contained within a 2-cm margin on the MRI GTV. One recurrence (8%) was located outside the 95% isodose surface. CONCLUSIONS: High-grade glioma contours obtained with (18)F-FDOPA PET had similar interobserver agreement to volumes obtained with MRI. Although PET-based consensus target volumes were larger than MRI-based volumes, treatment planning using PET-based volumes may not have yielded better treatment outcomes, given that all but 1 recurrence extended beyond the PET GTV and most were contained by a 2-cm margin on the MRI GTV.


Asunto(s)
Neoplasias Encefálicas , Dihidroxifenilalanina/análogos & derivados , Glioma , Imagen por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Adulto , Anciano , Astrocitoma/diagnóstico por imagen , Astrocitoma/patología , Astrocitoma/radioterapia , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Medios de Contraste , Dihidroxifenilalanina/farmacocinética , Femenino , Radioisótopos de Flúor/farmacocinética , Gadolinio , Glioblastoma/diagnóstico por imagen , Glioblastoma/patología , Glioblastoma/radioterapia , Glioma/diagnóstico por imagen , Glioma/patología , Glioma/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Imagen Multimodal/métodos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/radioterapia , Variaciones Dependientes del Observador , Oligodendroglioma/diagnóstico por imagen , Oligodendroglioma/patología , Oligodendroglioma/radioterapia , Radiofármacos/farmacocinética , Planificación de la Radioterapia Asistida por Computador , Sensibilidad y Especificidad , Carga Tumoral , Adulto Joven
20.
Int J Radiat Oncol Biol Phys ; 87(3): 528-33, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23953637

RESUMEN

PURPOSE: To assess the long-term disease control and toxicity outcomes of fractionated stereotactic radiation therapy (FSRT) in patients with pituitary adenomas treated at the BC Cancer Agency. METHODS AND MATERIALS: To ensure a minimum of 5 years of clinical follow-up, this study identified a cohort of 76 patients treated consecutively with FSRT between 1998 and 2007 for pituitary adenomas: 71% (54/76) had nonfunctioning and 29% (22/76) had functioning adenomas (15 adrenocorticotrophic hormone-secreting, 5 growth hormone-secreting, and 2 prolactin-secreting). Surgery was used before FSRT in 96% (73/76) of patients. A median isocenter dose of 50.4 Gy was delivered in 28 fractions, with 100% of the planning target volume covered by the 90% isodose. Patients were followed up clinically by endocrinologists, ophthalmologists, and radiation oncologists. Serial magnetic resonance imaging was used to assess tumor response. RESULTS: With a median follow-up time of 6.8 years (range, 0.6 - 13.1 years), the 7-year progression-free survival was 97.1% and disease-specific survival was 100%. Of the 2 patients with tumor progression, both had disease control after salvage surgery. Of the 22 patients with functioning adenomas, 50% (11/22) had complete and 9% (2/22) had partial responses after FSRT. Of the patients with normal pituitary function at baseline, 48% (14/29) experienced 1 or more hormone deficiencies after FSRT. Although 79% (60/76) of optic chiasms were at least partially within the planning target volumes, no patient experienced radiation-induced optic neuropathy. No patient experienced radionecrosis. No secondary malignancy occurred during follow-up. CONCLUSION: In this study of long-term follow-up of patients treated for pituitary adenomas, FSRT was safe and effective.


Asunto(s)
Adenoma/cirugía , Neoplasias Hipofisarias/cirugía , Radiocirugia/métodos , Adenoma/metabolismo , Adenoma/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Colombia Británica , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Quiasma Óptico/efectos de la radiación , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/mortalidad , Radiocirugia/efectos adversos , Terapia Recuperativa/métodos , Resultado del Tratamiento , Adulto Joven
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