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EP-1360: Analysis of the causes of recurrence after multimodality treatment of medulloblastoma in children
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Results: 40 cases were found, with a median of age of 3 years old. Out of all the cases, 2 were bilateral and 26 had no metastasis at the time of diagnosis. According to SIOP risk classification, 6 were high risk and the remaining were intermediate risk. According to SIOP stage: stage I (22), stage II (4),stage III (3) and stage 4 (10), stage V (1). All were treated with surgery (nephrectomy). 5 of them were not treated with neoadjuvant chemotherapy with vincristine and actinomicine, with or without doxorrubicine, and only one of them was not submitted to adjuvant chemoterapy with the same drugs. The most important toxicity related to chemoterapy ocurred in patients submitted to adjuvant chemotherapy: myelossupression (7) and infection (9); there were 2 cases of peripheral neuropathy, 1 case of liver toxicity and 1 case of heart toxicity. 8 patients were treated with adjuvant radiotherapy (3DCRT), with doses between 10.5 Gy to 21 Gy. Acute toxicity related to radiotherapy ocurred in 1 patient (gastrointestinal, grade 1, RTOG). No late side effects related to radiotherapy have been found yet. Patients submitted to radiotherapy had no loco-regional relapse. Out of 40 patients, 4 had died at the time of analysis, one of them had locoregional relapse, and 3 had distant metastasis. Conclusions: Recent developments in diagnostic methods and treatments are the main cause of improvement of prognosis in children with Wilms' tumor. Despite the limited number of patients presented, our results are in accordance to the available literature (90% overall survival at 5 years). EP-1359 Role of radiotherapy for localized cerebral ATRT in childhood: A pediatric radiotherapy group study V. Beneyton1, C. Dufour2, C. Carrie1 1 Centre Léon Bérard, Department of Radiotherapy, Lyon, France 2 Institut Gustave Roussy, Department of Pediatric, Villejuif, France Purpose/Objective: Atypical teratoid and rhabdoid tumors (ATRT) are rare and aggressive tumors which occur most commonly in young children. Strategy including surgery, radiotherapy and chemotherapy seems recommended but prognosis remains poor. We report one of the largest multicentric serie and we try to establish the role of radiotherapy on outcome. Materials and Methods: This is an exhaustive retrospective multicentric French report. We search all pediatric French patients which are treated for a cerebral ATRT (or PNET to not miss a secondary diagnosis considering INI1) between 1999 and 2010. Twenty nine children were treated with an association of surgery, radiotherapy and chemotherapy. The median age was two years old and seventeen children were less than three years old at time of diagnosis. Tumors were more frequently located in posterior fossa. Sugery was respectively complete, partial or biopsy in fifteen, twelve and two children. All but three receive chemotherapy. Results: Radiation dose delivered in tumor bed was 45 to 59, 4 Gy. Four patients were treated with craniospinal irradiation. Fifteen patients are dead and fourteen patients are alive with a median time of follow-up of two years after diagnosis. We find four isolated local relapses, seven metastatic diseases and six local and metastatic relapses. Results will have to precise the time of relapse after radiotherapy, the location of local relapse concerning doses delivered and concerning the time of irradiation after surgery. Conclusions; Preliminary results seem to show the effect of radiation therapy in terms of local control. Reduce delay between surgery and radiation therapy could avoid local relapse. Delivered doses and prescribed margins had to be precise to ameliorate the bad prognosis of ATRT in children. EP-1360 Analysis of the causes of recurrence after multimodality treatment of medulloblastoma in children D.H. Shonus1, O.I. Shcherbenko1, T.R. Izmailov1 1 Russian Scientific Center of Roentgenoradiology, Department of Clinical Oncology, Moscow, Russian Federation Purpose/Objective: The aim of our study was to investigate the incidence and causes of recurrence after multimodality treatment of medulloblastoma. Materials and Methods: During the period from 2009 to 2012 in the pediatric ward of RSCRR conducted chemoradiotherapy 132 children and adolescents with medulloblastoma. Patients received postoperative radiation therapy with craniospinal irradiation total dose and a boost of 35-40Gy to the tumor bed total dose 55 Gy in a gamma unit and a linear
ESTRO 33, 2014 accelerator. The brain was exposed to two opposing curved fields with shielding of the anterior orbit and facial bones, spinal cord in a gamma unit straight back fields at the linear accelerator 16-20 MeV electron beam. In parallel, received chemotherapy with Vincristine at a dose of 1.5 mg/m 2 weekly tively. Subsequently, patients received chemotherapy program. Results: In the long-term period (24-60 months after discharge), 9 of 132 patients (6.8%) contacted the office again due to recurrent disease. Localization of recurrence was as follows: spinal cord - 4 (3 %), multiple metastases to the brain - 1 (0.75 %), metastases in the temporal lobe - 3 (2.3%), in the fronto-parietal region -1(0.75 %) in chiasmo-sellar region 1 (0.75%) and 4 ventricle in 2 (1.5%) patients. In the analysis of the possible causes of relapse revealed the following: 1. When initially released by the process (stage M3) suggests failure of so-called 'Protocol' dose (35Gy to the whole volume of craniospinal axis and 45Gy to the area defined by the screenings of the spinal space and 55Gy to the primary site of the tumor 2. Uneven dose field due to insufficient irradiation fronto-basal parts of the brain and joints irradiation fields spinal cord. Conclusions: The method of radiation therapy for medulloblastomas in need of improvement that can be expressed: 1.to increase the total dose of radiation throughout the CNS in prognosis unfavorable cases (presence of cancer screenings rendered by the CNS, prognosis unfavorable morphological structure of the tumor). 2. Change irradiation technique ensuring uniform dose distribution throughout the irradiated volume through the use of locking devices to ensure patient immobility and identity installation and use of MLC collimator for radiation therapy the total area of the brain and primary tumor. EP-1361 Knowledge-based planning and evaluation - a pilot DVH registry for pediatric cranio-spinal irradiation K. John1, C. Freeman2, A. Joseph1, W. Parker1 1 McGill University Health Centre, Medical Physics, Montreal, Canada 2 McGill University Health Centre, Radiation Oncology, Montreal, Canada Purpose/Objective: To demonstrate the use and usefulness of a DVH registry for treatment planning and evaluation through application to pediatric intensity-modulated cranio-spinal irradiation (IMRT-CSI). Materials and Methods: Treatment planning for complex and infrequently-utilized techniques such as pediatric IMRT-CSI is often complicated by the first-principles manner in which planning is achieved. Owing to the low frequency of the technique, planners and physicians alike often refer to previously-treated plans for guidance. We hypothesized that this crude form of 'knowledge-based' planning could be greatly facilitated by a registry in which previously-treated plans are accessible in an automated fashion. As a first step, we have developed a DVH registry, and as a pilot study we registered the DVHs from recentlytreated pediatric IMRT-CSI plans. The registry allows us to define ab initio a 'standard' plan with standard dose-volume constraints derived from a cohort of previously-treated plans. The backbone of the registry is an SQL database that stores DVH data; the front-end provides web pages via a web-server on our centre's intranet. Before submission to the database, each patient's treatment plan data are anonymised and structures are renamed using a naming convention. The registry allows for addition of future plans as they are produced, such that the data set is always current. Results: We have used our DVH registry to produce standard (mean and median) DVHs for an initial demonstrative cohort of ten recently-treated pediatric IMRT-CSI patients treated to 36 Gy. Initial results have demonstrated the usefulness of the registry for CSI treatment planning. In particular, we were able to produce standard dose-volume constraints for IMRT-CSI that serve as useful starting points for inverse planning and useful comparison data for plan evaluation. Subsequent to our pilot study we have improved upon the userfriendliness of the system and we are presently rolling it out for full clinical use incorporating data for prostate and head and neck treatment plans. Conclusions: We have demonstrated the usefulness of a DVH registry as an aid for knowledge-based planning and plan evaluation using pediatric IMRT-CSI treatment plans.
Results: 40 cases were found, with a median of age of 3 years old. Out of all the cases, 2 were bilateral and 26 had no metastasis at the time of diagnosis. According to SIOP risk classification, 6 were high risk and the remaining were intermediate risk. According to SIOP stage: stage I (22), stage II (4),stage III (3) and stage 4 (10), stage V (1). All were treated with surgery (nephrectomy). 5 of them were not treated with neoadjuvant chemotherapy with vincristine and actinomicine, with or without doxorrubicine, and only one of them was not submitted to adjuvant chemoterapy with the same drugs. The most important toxicity related to chemoterapy ocurred in patients submitted to adjuvant chemotherapy: myelossupression (7) and infection (9); there were 2 cases of peripheral neuropathy, 1 case of liver toxicity and 1 case of heart toxicity. 8 patients were treated with adjuvant radiotherapy (3DCRT), with doses between 10.5 Gy to 21 Gy. Acute toxicity related to radiotherapy ocurred in 1 patient (gastrointestinal, grade 1, RTOG). No late side effects related to radiotherapy have been found yet. Patients submitted to radiotherapy had no loco-regional relapse. Out of 40 patients, 4 had died at the time of analysis, one of them had locoregional relapse, and 3 had distant metastasis. Conclusions: Recent developments in diagnostic methods and treatments are the main cause of improvement of prognosis in children with Wilms' tumor. Despite the limited number of patients presented, our results are in accordance to the available literature (90% overall survival at 5 years). EP-1359 Role of radiotherapy for localized cerebral ATRT in childhood: A pediatric radiotherapy group study V. Beneyton1, C. Dufour2, C. Carrie1 1 Centre Léon Bérard, Department of Radiotherapy, Lyon, France 2 Institut Gustave Roussy, Department of Pediatric, Villejuif, France Purpose/Objective: Atypical teratoid and rhabdoid tumors (ATRT) are rare and aggressive tumors which occur most commonly in young children. Strategy including surgery, radiotherapy and chemotherapy seems recommended but prognosis remains poor. We report one of the largest multicentric serie and we try to establish the role of radiotherapy on outcome. Materials and Methods: This is an exhaustive retrospective multicentric French report. We search all pediatric French patients which are treated for a cerebral ATRT (or PNET to not miss a secondary diagnosis considering INI1) between 1999 and 2010. Twenty nine children were treated with an association of surgery, radiotherapy and chemotherapy. The median age was two years old and seventeen children were less than three years old at time of diagnosis. Tumors were more frequently located in posterior fossa. Sugery was respectively complete, partial or biopsy in fifteen, twelve and two children. All but three receive chemotherapy. Results: Radiation dose delivered in tumor bed was 45 to 59, 4 Gy. Four patients were treated with craniospinal irradiation. Fifteen patients are dead and fourteen patients are alive with a median time of follow-up of two years after diagnosis. We find four isolated local relapses, seven metastatic diseases and six local and metastatic relapses. Results will have to precise the time of relapse after radiotherapy, the location of local relapse concerning doses delivered and concerning the time of irradiation after surgery. Conclusions; Preliminary results seem to show the effect of radiation therapy in terms of local control. Reduce delay between surgery and radiation therapy could avoid local relapse. Delivered doses and prescribed margins had to be precise to ameliorate the bad prognosis of ATRT in children. EP-1360 Analysis of the causes of recurrence after multimodality treatment of medulloblastoma in children D.H. Shonus1, O.I. Shcherbenko1, T.R. Izmailov1 1 Russian Scientific Center of Roentgenoradiology, Department of Clinical Oncology, Moscow, Russian Federation Purpose/Objective: The aim of our study was to investigate the incidence and causes of recurrence after multimodality treatment of medulloblastoma. Materials and Methods: During the period from 2009 to 2012 in the pediatric ward of RSCRR conducted chemoradiotherapy 132 children and adolescents with medulloblastoma. Patients received postoperative radiation therapy with craniospinal irradiation total dose and a boost of 35-40Gy to the tumor bed total dose 55 Gy in a gamma unit and a linear
ESTRO 33, 2014 accelerator. The brain was exposed to two opposing curved fields with shielding of the anterior orbit and facial bones, spinal cord in a gamma unit straight back fields at the linear accelerator 16-20 MeV electron beam. In parallel, received chemotherapy with Vincristine at a dose of 1.5 mg/m 2 weekly tively. Subsequently, patients received chemotherapy program. Results: In the long-term period (24-60 months after discharge), 9 of 132 patients (6.8%) contacted the office again due to recurrent disease. Localization of recurrence was as follows: spinal cord - 4 (3 %), multiple metastases to the brain - 1 (0.75 %), metastases in the temporal lobe - 3 (2.3%), in the fronto-parietal region -1(0.75 %) in chiasmo-sellar region 1 (0.75%) and 4 ventricle in 2 (1.5%) patients. In the analysis of the possible causes of relapse revealed the following: 1. When initially released by the process (stage M3) suggests failure of so-called 'Protocol' dose (35Gy to the whole volume of craniospinal axis and 45Gy to the area defined by the screenings of the spinal space and 55Gy to the primary site of the tumor 2. Uneven dose field due to insufficient irradiation fronto-basal parts of the brain and joints irradiation fields spinal cord. Conclusions: The method of radiation therapy for medulloblastomas in need of improvement that can be expressed: 1.to increase the total dose of radiation throughout the CNS in prognosis unfavorable cases (presence of cancer screenings rendered by the CNS, prognosis unfavorable morphological structure of the tumor). 2. Change irradiation technique ensuring uniform dose distribution throughout the irradiated volume through the use of locking devices to ensure patient immobility and identity installation and use of MLC collimator for radiation therapy the total area of the brain and primary tumor. EP-1361 Knowledge-based planning and evaluation - a pilot DVH registry for pediatric cranio-spinal irradiation K. John1, C. Freeman2, A. Joseph1, W. Parker1 1 McGill University Health Centre, Medical Physics, Montreal, Canada 2 McGill University Health Centre, Radiation Oncology, Montreal, Canada Purpose/Objective: To demonstrate the use and usefulness of a DVH registry for treatment planning and evaluation through application to pediatric intensity-modulated cranio-spinal irradiation (IMRT-CSI). Materials and Methods: Treatment planning for complex and infrequently-utilized techniques such as pediatric IMRT-CSI is often complicated by the first-principles manner in which planning is achieved. Owing to the low frequency of the technique, planners and physicians alike often refer to previously-treated plans for guidance. We hypothesized that this crude form of 'knowledge-based' planning could be greatly facilitated by a registry in which previously-treated plans are accessible in an automated fashion. As a first step, we have developed a DVH registry, and as a pilot study we registered the DVHs from recentlytreated pediatric IMRT-CSI plans. The registry allows us to define ab initio a 'standard' plan with standard dose-volume constraints derived from a cohort of previously-treated plans. The backbone of the registry is an SQL database that stores DVH data; the front-end provides web pages via a web-server on our centre's intranet. Before submission to the database, each patient's treatment plan data are anonymised and structures are renamed using a naming convention. The registry allows for addition of future plans as they are produced, such that the data set is always current. Results: We have used our DVH registry to produce standard (mean and median) DVHs for an initial demonstrative cohort of ten recently-treated pediatric IMRT-CSI patients treated to 36 Gy. Initial results have demonstrated the usefulness of the registry for CSI treatment planning. In particular, we were able to produce standard dose-volume constraints for IMRT-CSI that serve as useful starting points for inverse planning and useful comparison data for plan evaluation. Subsequent to our pilot study we have improved upon the userfriendliness of the system and we are presently rolling it out for full clinical use incorporating data for prostate and head and neck treatment plans. Conclusions: We have demonstrated the usefulness of a DVH registry as an aid for knowledge-based planning and plan evaluation using pediatric IMRT-CSI treatment plans.