ESTRO 36 Abstract Book

S618 ESTRO 36 _______________________________________________________________________________________________

1 Barretos Cancer Hospital, Radiation Oncology, Barretos, Brazil 2 UCLA, Radiation Oncology, Los Angeles, USA Purpose or Objective To evaluate the clinical outcomes with linear accelerator- based multifraction stereotactic radiosurgery (mSRS), 3 fractions, to treatment of the large Brain Metastasis in Patients with brain metastases were included with 30 days or more of the end of the mSRS, between May 2015 to August 2016. The primary endpoint was acute toxicity and the secondary endpoints were overall survival, local control (in field) and Regional recurrence free survival. Prognostic factors were analyzed, as Ds-GPA, RPA, the number of treated lesions, the major lesion, time between the last chemotherapy and procedure, fractionation (7, 8 or 9 Gy / fraction). The acute toxicity scale used was the RTOG / EORTC. For the survival curve calculations were used Kaplan- Mayer and Log-Rank test. To compare different categories of the same variable was used chi-square test. The significance level was 0.05. Results Were treated 51 patients, corresponding 110 lesions, 49% patients had one lesion. The study showed median follow- up of 8.00 months (2.42– 13.57). The overall survival (OS) estimated at 6 and 12 months were 58% and 43% respectively, with 84% non-neurologic deaths at 12 months. The primary sites were lung (39.2%), breast (29.4%) and colon/rectum (15.7%). The 9 Gy/fractions was the most used in 84.3% patients, 5.9% were treated with 8 Gy/fraction and 9.8% with 7 Gy/fraction. The median KPS was 80% (50-100%). Of the DS-GPA found, 31.9% had 0 – 1, 38.3% was 1.5 - 2.5 and 3 – 4 in 29.8%. The most of the RPA was 2 (45.1%). There were influence of the RPA and Ds- GPA in overall survival. The local control estimated at 12 months was 81%. There wasn’t statistical significance between local control with fraction, GTV and PTV volume, WBRT and Primary tumor. Toxicity Grade 2 was 31 % (most common was seizure, 16%). The regional recurrence free survival were 69.2% and 43% in 6 and 12 months. There were 3 patients with acute grade 3 CNS toxicity. Radionecrosis was observed in 6% of patients until this moment, and we had 2 “radiation Recall” episodes, after FOLFOX chemotherapy. There weren’t relation between toxicity and Radionecrosis with dosimetric and clinical variables, as Conformity Index, Brain Volume receiving 24 Gy, number of lesions, fractionation, etc. Conclusion Until this moment, our trial showed that mSRS is safe and feasibility, with excellent local control rates and low toxicity. Despite the most patients showed regional failure, out of field, death by neurologic causes was very low, just 15%. More patients included and longer follow- up must be help in improve and confirm the efficiency of this strategy. EP-1134 Head and neck DLBCL in HIV-positive patients: long-term results in the HAART era F. De Felice 1 , L. Grapulin 1 , A. Di Mino 1 , J. Dognini 1 , D. Musio 1 , V. Tombolini 1 1 Policlinico Umberto I- Sapienza Università Roma, Radiotherapy, Rome, Italy Purpose or Objective To report long-term outcomes and toxicity rates after chemotherapy (CHT) followed by radiotherapy (RT) in the Brazilian Population. Material and Methods Electronic Poster: Clinical track: Haematology

highly active antiretroviral therapy (HAART) era in human immunodeficiency virus (HIV) positive patients with head and neck diffuse large B-cell lymphomas (HN-DLBCL). Material and Methods Clinical data concerning consecutive HIV patients treated for DLBCL located in head and neck region with CHT and RT between January 1995 and August 2010 were retrospectively reviewed. Systemic treatment consisted of combination CHT agents given with concomitant HAART and regimen was left to oncologists’ discretion. Involved field RT was delivered with a 3D-conformational technique at a total dose of 30/36 Gy (2 Gy per fraction). Survival rates were estimated using the Kaplan–Meier method. Toxicity was evaluated using National Cancer Institute’s Common Terminology Criteria for Adverse Events. Results Overall, 13 patients were included. There were no missing data. Seven patients had limited disease (stage I = 3; stage II = 4) and 6 patients had stage IV disease. Primary tumour location was sinus (n = 4), oral cavity (n = 7), nasopharynx (n = 1) and larynx (n = 1). All patients completed the programmed treatment. Overall, 4 patients had died. No treatment-related deaths were recorded. The 10-year, 15-year and 20-year overall survival (OS) rates were 87.5% (95% confidence interval [CI] 0.387 – 0.981), 62.5% (95% CI 0.229 – 0.861) and 50% (95% CI 0.152 – 0.775), respectively. Median OS was 168 months. Details are shown in Figure 1. In total, only 1 patient had local relapse, 10 years after the end of RT. The patient received CHT and is still alive without evidence of disease. No patients had developed distant metastasis. Globally, there were no RT-related late complications. One patient had a second cancer arising from cervix, 5 years after the end of treatment.

Conclusion This data analysis suggested that CHT followed by RT can be safety proposed in the management of patients with HIV-related HN-DLBCL in the HAART era. Combined modality therapy reduced local recurrence rates and achieved a high response rate, without chronic toxicity. EP-1135 Radiotherapy in primary CNS lymphoma R. Muni 1 , G. Grittii 2 , L. Feltre 1 , F. Filippone 1 , E. Iannacone 1 , M. Kalli 1 , L. Maffioletti 1 , F. Piccoli 1 , S. Takanen 1 , L. Cazzaniga 1 1 ASST Papa Giovanni XXIII, Radiation Oncology, Bergamo, Italy 2 ASST Papa Giovanni XXIII, Haematology, Bergamo, Italy Purpose or Objective Primary CNS lymphoma(PCNSL) is a rare and aggressive brain tumor with poor prognosis. Patients are primarily treated with high dose chemotherapy while radiotherapy plays a role as consolidation after chemotherapy. Total dose and fractionation are not well established. In patients older than 60 years the incidence is higher with a worse outcome. The management of these patients is