ESTRO 38 Abstract book

S695 ESTRO 38

J. Lee 1 , D. Oh 2 , B.O. Choi 3 , K.Y. Eom 4 , J.H. Lee 5 , J.H. Kim 6 , S.W. Lee 7 , Y.K. Suh 8 , C. Suh 9 1 Inha University Hospital, Radiation Oncology, Incheon, Korea Republic of ; 2 Samsung Medical Center- Sungkyunkwan University College of Medicine, Department of Radiation Oncology, Seoul, Korea Republic of ; 3 Seoul St. Mary’s Hospital, Department of Radiation Oncology, Seoul, Korea Republic of ; 4 Seoul National University Bundang Hospital, Department of Radiation Oncology, Seongnam, Korea Republic of ; 5 St. Vincent's Hospital, Department of Radiation Oncology, Suwon, Korea Republic of ; 6 Kunyang University Hospital, Department of Radiation Oncology, Seoul-, Korea Republic of ; 7 Asan Medical Center- Ulsan University College of Medicine, Department of Radiation Oncology-, Seoul, Korea Republic of ; 8 National Cancer Center, Department of Radiation Oncology, Ilsan, Korea Republic of ; 9 Yonsei Cancer Center- Yonsei University College of Medicine, Department of Radiation Oncology, Seoul, Korea Republic of Purpose or Objective Radiotherapy (RT) is an effective primary treatment for orbital mucosa-associated lymphoid tissue (MALT) lymphoma historically. Recent few studies reported the association between Chlamydia psittaci infection and orbital MALT lymphoma. We aimed to assess the current patterns of care in clinical practice for orbital MALT lymphoma in South Korea. Material and Methods We performed a multicenter, cross-sectional cohort study of patterns of care for orbital MALT lymphoma in South Korea throughout 2016, and overall 8 institutions with 90 patients were participated. All patients diagnosed with orbital MALT lymphoma based on a pathologic confirmation. Results The survey showed that most frequent upfront treatment for orbital MALT lymphoma was RT (80/90, 90%). Other treatments were given to a limited number of orbital MALT lymphoma patients as follows: wait and watch (6/90, 7%), antibiotics (3/90, 3%), and chemotherapy (1/90, 1%). Generally, RT was administered to the entire involved site such as entire conjunctiva/eyelid or entire orbit (96%), with a median total dose of 25.2 Gy. Lens shielding was performed for most patients with conjunctival and eyelid tumors (93%). Conclusion Our findings revealed that RT was the mainstream of orbital MALT lymphoma treatment. Currently, for patients with orbital MALT lymphoma, RT has been performed to the entire involved subsites with a lower dose compared to the past, and lens shielding is applied to minimize the orbital complication. EP-1265 Total Skin Irradiation - 15 years of Gliwice experiences G. Wozniak 1 , T. Latusek 1 , Z. Kaniszewska-Dorsz 1 , W. Mista 1 , B. Jochymek 1 , K. Lukasz 1 , W. Jerzy 1 , S. Blamek 1 1 Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Radiotherapy, Gliwice, Poland Purpose or Objective Evaluation of effectiveness and early toxicity of total skin radiation for patients with primary skin lymphoma Material and Methods Between 2002 and 2017 25 patients with pathological diagnosed primary skin lymphomas were treated with electron radiotherapy using total skin irradiation technique. Male to female ratio was 14 to 11. In almost all patients (22) mycosis fungoides were confirmed. Median age was 66 years. One patient was staged as T1 , 11 as T2, 10 as T3 and 3 as T4. Only three patients did not undergo any oncological therapy before radiation. All patients were irratated 6MeV electron beams using linac. Total

dose ranged between 6 to 36 Gy (median 32) given in 1,5- 2 Gy per fraction. In 6 cases additional boost fields for residual disease were used after the end of total skin treatment. Skin reactions and haematological toxicity were assesed with WHO score. OS and PFS were estimated using Kaplan Maier method. Results Median follow up was 20 months. Two patients have not completed treatment. Each patient had skin reaction: 18 were scored as 1st, 4 as 2nd and 1 as 3rd grade. There was not any haematological toxicity observed within the group. Other adverse effects included: alopecia 6pts, coniunctivitis 4pts, general weakness 3pts . In 79% pts disease symptoms regression were observed, including complete response in 20%. Progression was documented in 3 cases. Median time to progression was 7 months, and OS was 64 months. One year PFS was 36% and 5yrs OS was 67%. (Fig1) There was significant differences in PSF depending of T stage (p=0,028) (Fig2). No other factors influencing the OS and PFS were proven. Cox hazard analysis showed that clinical stage and disease regression 6 weeks after radiotherapy are independent risk factors for progression.

Conclusion TSI in skin lymphomas using 6Mev electrons is a safe treatment method yielding satisfactory yet short term response rate. Only clinical stage has impact on time to disease progression EP-1266 Combination radiotherapy with Nivolumab for refractory classic Hodgkin lymphoma : about two cases L. De Forceville 1 , B. Deau-Fischer 2 , P. Franchi 2 , A. Arsene-Henry 3 , T. Cassou Mounat 4 , D. Bouscary 2 , Y. Kirova 3 1 Hopital Tenon, oncologie médicale, Paris, France ; 2 Hopital Cochin, Hématologie, Paris, France ; 3 Institut Curie, Radiothérapie, Paris, France ; 4 Institut Curie, Médecine Nucléaire, Paris, France