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Carnicer A.,Center Antoine Lacassagne | Angellier G.,Center Antoine Lacassagne | Thariat J.,Center Antoine Lacassagne | Sauerwein W.,University of Duisburg - Essen | And 2 more authors.
Medical Physics | Year: 2013

Purpose: Proton scattering on beam shaping devices and protons slowing down on media with different densities within the treatment volume may produce dose perturbations and range variations that are not predicted by treatment planning systems. The aim of this work was to assess the dosimetric impact of elements present in ocular proton therapy treatments that may disturb the prescribed treatment plan. Both distal beam shaping devices and intraocular elements were considered. Methods: A wedge filter, tantalum fiducial marker, hemispherical compensator, two intraocular endotamponades (densities 0.97 and 1.92 g cm -3) and an intraocular eye lens (IOL) were considered in the study. For these elements, longitudinal dose distributions were measured and/or calculated in water in beam alignment for a clinical spread-out Bragg peak. Under the same conditions, the unperturbed dose distributions were similarly measured and/or calculated in the absence of the element. The dosimetric impact was assessed by comparison of unperturbed and perturbed dose distributions. Measurements and calculations were carried out with two methods. Measurements are based on EBT3 films with dedicated software, which makes use of a calibration curve and correction for the quenching effect. Calculations are based on the Monte Carlo (MC) code MCNPX and reproduce the experimental conditions. Both dose maps are obtained with a resolution of 300 dpi. Results: The degree of disturbance of distal beam shaping devices is low for the wedge filter (2% overdose ripple all along the central axis) and moderate for the hemispherical compensator (two bands of variable overdose of up to 10% downstream the compensator lateral edges and -5% underdose on the plateau at off-axis distance of 5 cm). Tantalum clips produce important dose shadows (-20% behind the clip parallel to the beam and range reduction of 1.1 mm) and bands of overdose (15%). The presence of endotamponades modifies the dose distribution very significantly (-5% underdose on the plateau and 3 mm range prolongation for the tamponade with density 0.97 g cm-3 and -15% underdose on plateau and 8 mm range reduction for that with density 1.92 g cm-3). No dose perturbations were found for the IOL. The high performance of EBT3 film and MC tools used was confirmed and good agreement was found between them (percentage of pixels passing the gamma test >87%). Conclusions: The degree of disturbance by external beam shaping devices remains low in ocular proton therapy and can be reduced by bringing accessories closer to the eye. Tantalum fiducial markers must be located in such a way that dose perturbation is not projected on the tumor. The treatment of patients with intraocular endotamponades must be carefully managed. It is fundamental that radiation oncologists and medical physicists are informed about the presence of such substances prior to the treatment. © 2013 American Association of Physicists in Medicine. Source


Baillif S.,Saint Roch Hospital | Cornut P.-L.,Edouard Herriot Hospital | Girard C.,Edouard Herriot Hospital | Ghesquieres H.,Leon Berard Center | Perard L.,Edouard Herriot Hospital
Retinal Cases and Brief Reports | Year: 2011

Purpose: To report atypical ocular manifestations in two patients with undiagnosed Hodgkin lymphoma. Methods: Observational case report. Results: The first patient, a 27-year-old man, presented with bilateral acute angleclosure glaucoma secondary to uveal effusion. Histopathology of chest lymph nodes obtained by mediastinoscopy revealed nodular sclerosing Hodgkin lymphoma. Ocular signs resolved after systemic chemotherapy. The second patient, a 56-year-old man, presented with bilateral multifocal choroiditis. Extensive biologic and microbiologic examinations were negative. Pathologic lymph nodes were detected in the anterior mediastinum. The histopathologic examination of the nodes after mediastinoscopy revealed nodular sclerosing Hodgkin lymphoma. Systemic chemotherapy was instituted. The patient encountered a major increase in the multifocal choroiditis within 3 days after the second chemotherapy injection. High-dose intravenous corticosteroid therapy was initiated. No recurrence of choroidal lesions was observed after the treatment completion. Conclusion: These two patients presented with bilateral paraneoplastic uveal tract involvement as initial presentation of Hodgkin lymphoma. Systemic corticosteroid therapy may be associated with systemic chemotherapy to obtain complete remission of the ocular inflammatory activity. © Lippincott Williams & Wilkins. Source


Caujolle J.-P.,Saint Roch Hospital | Mammar H.,Protontherapy Center | Chamorey E.,Center Antoine Lacassagne | Pinon F.,Saint Roch Hospital | And 2 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2010

Purpose: To present the results of uveal melanomas treated at Nice Teaching Hospital. Methods and Materials: This retrospective study included 886 consecutive patients referred to our clinic for the treatment of uveal melanomas by proton beam radiotherapy from June 1991 to December 2007. Survival rates were determined by using Kaplan-Meier estimates, and prognostic factors were evaluated using the log-rank test or Cox model. Results: The number (percent total) of subjects staged according to the TNM classification system (6th edition) of malignant tumors included 39 stage T1 (4.4%), 420 stage T2 (47.40%), 409 stage T3 (46.16%), and 18 stage T4 (2.03%) patients. The median follow-up was 63.7 months. The Kaplan-Meier overall survival rate at 5 years according to the sixth edition TNM classification was 92% for T1, 89% for T2, 67% for T3, and 62% for T4; and at 10 years, 86% for T1, 78% for T2, 43% for T3, and 41% for T4. Five factors were found to be associated with an increased death rate: advanced age, tumor thickness, largest tumor basal diameter, tumor volume, and tumor volume-to-eyeball volume ratio. The metastasis-free survival rates were 88.3 % at 5 years and 76.4 % at 10 years. The local control rates were 93.9% at 5 years and 92.1% at 10 years. The ocular conservation rates were 91.1% at 5 years and 87.3% at 10 years. Conclusions: We report the results of a large series of patients treated for uveal melanomas with a very long follow-up. Despite the large tumor volume treated, our results were similar to previously published findings relating to proton beam therapy. © 2010 Elsevier Inc. Source


Caujolle J.-P.,Saint Roch Hospital | Paoli V.,Saint Roch Hospital | Chamorey E.,Protontherapy Center | Chamorey E.,Center Antoine Lacassagne | And 5 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2013

Purpose: To study the prognosis of the different types of uveal melanoma recurrences treated by proton beam therapy (PBT). Methods and Materials: This retrospective study analyzed 61 cases of uveal melanoma local recurrences on a total of 1102 patients treated by PBT between June 1991 and December 2010. Survival rates have been determined by using Kaplan-Meier curves. Prognostic factors have been evaluated by using log-rank test or Cox model. Results: Our local recurrence rate was 6.1% at 5 years. These recurrences were divided into 25 patients with marginal recurrences, 18 global recurrences, 12 distant recurrences, and 6 extrascleral extensions. Five factors have been identified as statistically significant risk factors of local recurrence in the univariate analysis: large tumoral diameter, small tumoral volume, low ratio of tumoral volume over eyeball volume, iris root involvement, and safety margin inferior to 1 mm. In the local recurrence-free population, the overall survival rate was 68.7% at 10 years and the specific survival rate was 83.6% at 10 years. In the local recurrence population, the overall survival rate was 43.1% at 10 years and the specific survival rate was 55% at 10 years. The multivariate analysis of death risk factors has shown a better prognosis for marginal recurrences. Conclusion: Survival rate of marginal recurrences is superior to that of the other recurrences. The type of recurrence is a clinical prognostic value to take into account. The influence of local recurrence retreatment by proton beam therapy should be evaluated by novel studies. © 2013 Elsevier Inc. Source


Baillif S.,Saint Roch Hospital | Maschi C.,Saint Roch Hospital | Gastaud P.,Saint Roch Hospital | Caujolle J.P.,Saint Roch Hospital
Retina | Year: 2013

PURPOSE:: To evaluate the efficacy of dexamethasone 0.7-mg intravitreal implant in patients with radiation macular edema after proton beam therapy for choroidal melanoma. METHODS:: Five patientsÊ charts were retrospectively reviewed. The main outcome measures were visual acuity and mean central retinal thickness. RESULTS:: All patients received a radiation dose of 60 cobalt gray equivalent. Radiation macular edema occurred within a mean time of 26 months after irradiation. Mean preinjection visual acuity was 41 Early Treatment Diabetic Retinopathy Study letters. Mean central retinal thickness was 487.1 μm. Two months after injection, mean visual acuity was 47 Early Treatment Diabetic Retinopathy Study letters. It improved for 3 patients (+4, +9 and, +15 letters) and remained unchanged for 2. Mean central retinal thickness was 331 μm. It decreased for 4 patients (-111,-134,-336, and-187 μm). Two patients underwent a second injection of dexamethasone performed 5 months after the first injection. The gain of visual acuity was +8 and +23 letters with a decrease in central retinal thickness of 158 and 262 μm, respectively. Intraocular pressure increased for 1 patient over a mean follow-up period of 6.4 months. CONCLUSION:: Intravitreal dexamethasone implant can improve visual acuity in radiation macular edema. The observed beneficial effect lasted up to 5 months. © by Ophthalmic Communication Society Inc. Source

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