Abstract book - ESTRO meets Asia

S15 ESTRO meets Asia 2018

Teaching lecture: Rare tumours

modality in early stage HL or DLBCL have administered the radiation at a dose of 30/40 Gy. Short- and long-term toxicities increase as the dose of radiation increases. Additionally, FGD-PET/CT provides the precise information of efficacy of pharmaceutical treatments such as complete metabolic response (CMR). For patients with favorable HL who are treated with standard ABVD and get CMR, the dose of 20 Gy appear to be associated with less short-term toxicity and similar efficacy, while additional follow-up is necessary to investigate for long-term outcomes (N Engl J Med. 2010;363(7):640). And for same CMR setting of unfavorable HL 30 Gy is recommended. For patients with CMR of earl stage DLBCL treated with full intensity of RCHOP, 30 Gy appear to be enough and safe (Radiother Oncol. 2011;100(1):86.). In settings where the efficacy of chemotherapy is less certain (residual MLs post chemotherapy, salvage therapy) high RT dose could be considered. It is uncommon but for some patient with severe comorbidity or the elderly who are classified with contra-indication category of above-mentioned pharmaceutical treatments, keep in mind, medium dose with modern RT technique provide excellent local control and higher patient’s QOL than best supportive care or observation. For indolent lymphomas such as FL and Marginal zone B- cell lymphoma (MZL) recommended RT dose are 24 Gy based on the phase 3 randomized trials (Radiother Oncol. 2011;100(1):86.). The overall response rate was 93 percent. A higher dose can be considered for patients with bulky lesion but should not exceed 30 Gy. Another phase 3 randomized non-inferiority trial demonstrates unacceptably higher rate of lymphoma progression with 4 Gy RT (22 versus 7 percent) than 24 Gy. The 4 Gy RT is not appropriate in the setting of limited stage indolent MLs treated with curative intent. Generally, majorities of MLs are responsive to RT, 4 Gy RT can be used for the palliation of patients who have symptoms (Int J Radiat Oncol Biol Phys. 2013;86(1):121- 7). The International Lymphoma Radiation Oncology Group (ILROG) has been publishing several guidelines addressing with the appropriate RT doses in many of clinical scenarios including initial treatment, salvage and palliation for MLs arising any organs. The ILROG are pleased to invite you to the 3rd ILROG Educational Conference: Radiotherapy in Modern Lymphoma Management, to be held in Tokyo on the 6th & 7th of April, 2019. The Conference will be held at the TFT HALL, Tokyo Big Sight. http://ilrogtokyo2019.umin.jp/index.html SP-041 Lymphoma and volumes: when and how much is safe to reduce them\r A. Wirth 1 1 Peter MacCallum Cancer Centre, Department of Radiation Oncology, Melbourne, Australia Abstract text Lymphoma and radiotherapy volumes: when and how much is it safe to reduce them? Radiotherapy volumes for lymphoma treatment have undergone progressive reduction since sub-total nodal irradiation (STNI) was introduced as a curative treatment for Hodgkin lymphoma (HL) in an era when imaging was limited and chemotherapy was relatively ineffective and toxic. Involved-field radiotherapy (IFRT) was later demonstrated to have equal efficacy to STNI when combined with chemotherapy, and was subsequently adopted as standard of care for most lymphoma sub-types. IFRT is "generous" enough to allow for some uncertainties in disease localisation, chemotherapy efficacy (for subclinical regional disease) and radiotherapy planning and delivery, but at a cost of often exposing potentially avoidable normal tissue.

SP-036 CNS Pediatric Tumors: Clinical trials, technologies and outcome U. Ricardi 1 University of Torino, Radiation Oncologist, Torino ,Italy

Abstract not received

SP-037 Sarcoma(s) and brachytherapy: technologies and outcome L.Siddharta 1 1 Tata Memorial Hospital, Radiation Oncology, Mumbai, India

Abstract not received

Teaching lecture Normal tissue response and mechanisms

SP-038 Normal tissue response and mechanisms A. van der Kogel 1 University of Wisconsin Medical Radiation Research Center, Madison, WI USA

Abstract not received

Symposium: Putting knowledge at work in Lymphoma

SP-039 Modern therapeutic approaches in lymphoma: when RT is mandatory? U.Ricardi 1 1 University of Torino, Radiation Oncologist, Torino, Italy

Abstract not received

SP-040 Lymphoma and doses: when and how much is safe to reduce them M. Oguchi 1 1 Cancer Institute Hospital, Radiation Oncology, Tokyo, Japan Radiation therapy (RT) plays very important role on the local control of malignant lymphomas (MLs). However, the treatment of MLs requires a careful balance between providing enough therapy to eradicate the MLs and avoiding unnecessary treatment that could result in excessive long-term RT-related adverse effects. Historically, RT doses for MLs treatment have been reducing progressively, associated with the increased effectiveness of pharmaceutical treatments, improved imaging modality and improvements in radiotherapy planning and delivery (IMRT/VMAT+IGRT). In the ancient era when RT was applied as a single modality therapy for MLs, higher dose had been used than those of modern era, for examples, 30-36 Gy for follicular lymphoma(FL), 30-40 Gy for Hodgkin lymphoma(HL) and 50+ Gy for aggressive Non-Hodgkin lymphomas. In these last few decades, pharmaceutical treatments including combination chemotherapy and/or immunotherapy, such as ABVD for HL and R-CHOP for Diffuse large B-cell lymphoma (DLBCL), have been dramatically developed in terms of efficacy resulting higher survival rates than before. The majority of those clinical trials that have evaluated the use of combined Abstract text Putting knowledge at work in Lymphoma