ESTRO 38 Abstract book

S869 ESTRO 38

radiotherapy according to the protocol. Out of 18 children, 14 (78%) were male and 4 (22%) were females. Mean age of the children was 11 years (6 – 17years). All the patients were discussed in departmental peer review meeting with at least two radiation oncologists and a team of residents before starting radiotherapy.A total of 14 patients (77.8%) received both supra and infra diaphragmatic radiotherapy while two patients each had supra diaphragmatic and infra diaphragmatic radiation alone in phase I with total dose of 19.8Gy. Out of 14 patients who received radiation to both supra and infra-diaphragmatic regions, 9 (64%) patients received simultaneous supra & infra diaphragmatic radiation whereas 5 (35.7%) received sequential radiotherapy to the other region. Neck was irradiated in 16 (88.9%) patients, among them 9 patients received bilateral neck radiation. RT to axilla was given in 13 (72.2%) patients out of which bilateral axilla was treated in 9 patients. Spleen was treated in 12 (66.7%) patients. A phase II boost of 10 Gy was given to the regions of neck in 8 patients, axilla to 3 patients and spleen to 3 patients. None of these patients had a treatment gap during the course of radiation therapy. Also, no severe acute hematologic toxicity was observed after completion of Radiation therapy for children with Hodgkin’s disease was planned by peer reviewed team and delivered according to the protocol without any treatment interruption. Long term toxicity needs to be evaluated, possibly in a larger prospective study. EP-1612 Radiation induced hypothyroidism in pediatric tumours of central nervous system C. Satragno 1 , E. Tornari 1 , S. Barra 2 , F. Giannelli 2 , L. Belgioia 1 , M. Giaccardi 3 , N. Di Iorgi 3 , M.L. Garrè 4 , R. Haupt 5 , R. Corvò 1 1 University of Genoa and San Martino Hospital, Health Science Department DISSAL and Radiation Oncology, Genoa, Italy ; 2 San Martino Hospital, Radiation Oncology, Genoa, Italy ; 3 Istituto Giannina Gaslini, Department of Pediatrics, Genoa, Italy ; 4 Istituto Giannina Gaslini, Department of Neurooncology, Genoa, Italy ; 5 Istituto Giannina Gaslini, Epidemiology and Biostatistics Unit, Genoa, Italy Purpose or Objective To investigate primary and secondary hypothyroidism in pediatric patients affected by central nervous system (CNS) tumors. Material and Methods From January 1999 to September 2015 we retrospectively analyzed all patients with CNS tumors treated by IMRT or 3D-CRT. We analyzed hypothyroidism from direct thyroid damage (primary hypothyroidism) with FT4 value and hypothyroidism from direct damage to the pituitary gland and hypothalamus (considering them as a single organ at risk - central hypothyroidism) with TSH detection. Results Sixty-four consecutive pts with a median age of 10 years (range: 2 to 17) were identified. Nineteen (29,7%) and 45 (70,3%) pts received IMRT and 3DCRT respectively. 39 (60.9%) patients underwent craniospinal irradiation (CSRT) ± boost; all other patients were treated with involved field radiation therapy (IFRT) ± boost (39.1%). Hystology was represented by medulloblastoma, gliomas, germinoma, ependymomas and others in 50%, 26.5%, 11%, 4.6% and 7.8% of patients, respectively. Sixty-one (95,3%) patients received chemotherapy (CT) and 42 (65,6%) patients surgery. Thyroid dose evaluation was possible in 20 of 39 patients who received CSRT, whereas a documented pituitary gland dose was available in 64 pts. 19/64 pts presented a TSH deficit and 6/64 fT4 deficit. Sixteen of 19 patients with TSH deficiency were treated with CSRT (dose treatment. Conclusion

EP-1611 Experience of uninterrupted radiotherapy for pediatric hodgkin’s disease in a developing country B.M. Qureshi 1 , Y. Ahmed 1 , F. Shaukat 1 , A.N. Abbasi 1 , M.R. Khan 2 , M.A. Mansha 1 , M.U. Karim 1 , A. Hafiz 1 , A.M.H. Khan 1 , B. Mir Khan 1 , N. Ali 1 , M.S. Ashraf 3 1 The Aga Khan University, Radiation Oncology Section- Department of Oncology, Karachi, Pakistan ; 2 The Indus Hospital, Department of Pediatric Oncology- Indus Children Cancer Hospital, Karachi, Pakistan ; 3 The Indus Hospital-, Department of Pediatric Oncology- Indus Children Cancer Hospital, Karachi, Pakistan Purpose or Objective Radiation therapy is an essential component of patients treated on Euronet protocol who have not responded to initial chemotherapy. The Purpose of the study is to report the planning and delivery experience of radiation therapy for pediatric Hodgkin’s disease patients at our tertiary care university hospital in Pakistan. Material and Methods All the patients with Hodgkin’s disease are discussed is site specific pediatric leukemia / lymphoma tumor board meeting. Patients having residual disease on interim evaluation after initial cycles of chemotherapy are treated with radiation therapy after the completion of appropriate chemotherapy according to treatment group. Radiation therapy is planned and delivered according to radiotherapy guidelines of Euronet PHL-C1 study treatment protocol. Children requiring radiation therapy are treated with a dose of 19.8 Gy in 11 fractions to the initial involved site with 1.8 Gy per fraction. A boost of 10 Gy in 5 fractions with 2 Gy per fraction is given to the residual disease seen on interim scan. Results From January 2017 till October 2018, a total of 18 patients of Hodgkin’s disease were identified who required