ESTRO 37 Abstract book

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ESTRO 37

Results Treatment course was well tolerated; all pts completed PT without breaks related to acute side effects. A conventional fractionation technique was used for 38 treatments, in 7 cases a Simultaneous Integrated Boost technique was used. All pts were treated with active beam scanning PT using a median of 3 fields with single field optimization technique. Mean high-risk (HR) PTV volume was 621,8 cc (range, 53,3 -2551,95 cc); mean low-risk (LR) PTV volume was 1099,2 cc (range, 72,9 – 3011,08 cc). Mean prescribed total dose was 67,7 GyRBE (range: 50-78 GyRBE) for HR PTV and 52,7 GyRBE (range, 50-54 GyRBE) for LR PTV. Acute G3 cutaneous toxicity was experienced in 9 pts. No other ≥ G3 acute side effects were reported. No late Grade ≥ 3 toxicities were recorded. Acute and late side effects are reported in the attached table. Pain was experienced in 8 pts during PT and the maximum grade was 8 NRS in one case and it persisted in 3 pts, grade1, 2 and 5 NRS. Median follow-up was 7,76 months (range, 0-25,3). Of the 33 lesions treated with radical intent, 22 are locally controlled, in 4 cases there was local progression, one pt had local and distant progression during PT, 4 pts died for the disease and 2 died of other causes. Of the 12 pts treated with adjuvant intent all are free of disease. Acute G1 G2 G3 G4 Cutaneous 15 8 9 - Fatigue 12 - - - Disphagia 5 2 - - Gastro-enteric 3 - - - Paresthesia 3 - - - Laryngitis 1 - - - Chronic G1 G2 G3 G4 Cutaneous 11 2 - - Hypoesthesia/Paresthesia 5 - - - Conclusion Our very preliminary data confirm that proton therapy for spine malignancies is a feasible irradiation modality associated with an excellent treatment tolerance and compliance. A longer follow-up is obviously needed to gain more robust data for late toxicity and long term disease control. EP-1639 Current situation and issues for promotion of childhood cancer radiation therapy in Japan H. Sekine 1 , T.H. Hashimoto 2 , K.J. Jingu 3 , M.K. Kita 4 , H.F. Fuji 5 , H.I. Igaki 6 , M.S. Sumi 7 , M.O. Omura 8 , M.K. Kawamura 9 , N.I. II 10 , A.T. Takada 11 , G.S. Suzuki 12 , T.M. Mizowaki 13 , M.T. Tanaka 14 , F.I. Isohashi 15 , T.S. Soejima 16 , T.K. Kimura 17 , S.O. Oga 18 , E.O. Ogo 19 , Y. Nagata 17 1 Jikei University Daisan Hospital, Department of Radiology and Radiotherapy, Komae, Japan 2 Hokkaido University Hospital, Radiation Therapy, Hokkaido, Japan 3 Tohoku University Hospital, Radiation Oncology, Sendai, Japan 4 Tokyo Metropolitan Tama Medical Center, Radiology, Fucyu, Japan 5 National Center for Child Health and Development, Radiation Therapy, Setagaya, Japan Electronic Poster: Clinical track: Paediatric tumours

the BSD 2000 deep hyperthermia unit. All patients received up to 6 hyperthermia sessions during the proton therapy. Temperature was monitored on the skin, in the rectum, gluteal fold and the urinary bladder. Acute and late toxicity was assessed according to CTCAE v4. Results From June 2016 to October 2017, 5 male patients were treated with PT and HT. Median patient age was 67 years (range, 57-71) and they had a median tumor size of 791 cc (range, 457-1361). Median follow-up (FU) was 6 months (range, 0-9). Median HT session number was 5 (range, 2-6). FU imaging showed slight tumor decrease in 3 patients at 6, 8 and 9 months following treatment. Last MRI showed stable disease in one patient and one patient had no FU imaging yet. Three patients presented initially with pain while two in addition had numbness. Three patients had initial dysuria. All 5 patients developed increased pain during the therapy and needed analgesics. None had ≥ 3 acute or late toxicities. Pain and numbness recovered in all during follow-up. Conclusion Early results in patients with large inoperable sacral chordomas undergoing combined treatment of PT and HT are encouraging with no grade ≥ 3 acute and late toxicities. All patients showed a significant reduction in their initial pretreatment symptoms. Early follow-up imaging showed either slight regression or stable tumor size. Initial clinical pretreatment symptoms decreased during FU in all patients. Therapy showed no grade ≥ 3 acute or late toxicities. These results are promising and warrant further confirmation in a prospective trial with a larger number of patients and a longer FU period. EP-1638 Trento Proton Therapy Centre Experience For Spine Chordoma, Chondrosarcomas And Other Sarcomas I. Giacomelli 1 , M. Cianchetti 1 , F. Dionisi 1 , D. Amelio 1 , D. Scartoni 1 , S. Vennarini 1 , M. Amichetti 1 1 Centro di Protonterapia, Protontherapy, Trento, Italy Purpose or Objective To report the initial clinical experience of Trento Proton Therapy Centre in treating chordomas (C), chondrosarcomas (CS) and other sarcomas (S) with protontherapy (PT) in terms of safety and feasibility. Material and Methods From December 2014 to September 2017 44 patients (pts) and 45 lesions were irradiated with protontherapy (PT). Mean age was 62.6 years (range: 17,8 – 84,1); mean KPS was 90 (range 50-100). There were 32 C, 5 CS, 1 Osteoblastoma and 1 Giant Cell Tumor, 1 Dedifferentiated Liposarcoma, 1 Malignant Peripheral Nerve Sheath Tumor, 1 Hemangioendothelioma, 2 Solitary Fibrous Tumor, 1 Leiomiosarcoma. Tumors were located in sacrococcyx n= 18, lumbar spine n= 13, cervical spine n= 8 and dorsal spine n= 6. Median diameter at the time of treatment was 60 mm (range 24-128). Ten lesions were only biopsied and treated with exclusive PT. Thirty five lesions had been treated with ≥ 1 surgery, of them 23 cases had gross residual disease at the beginning of PT in those cases PT was performed with radical intent, 12 cases were treated with adjuvant intent. Five macroscopical diseases had already previously been irradiated, 4 of them with photons at a total dose of 36 to 54 Gy and one, with protons at a total dose of 66 GyRBE. Toxicity was scored according to the CTCAE 4.0, pain was scored according to the Numerical Rate Scale (NRS).