ESTRO 38 Abstract book

S182 ESTRO 38

From February 2011 to December 2017, 15 patients with R/R HL (n=7), diffuse Large B Cell NHL (n=6) and T-cell NHL (n=2) were treated. Median age was 42 years (range 20-68) and median number of previous lines of therapy was 3 (range 2-4). Of note, 4 patients had already received prior ASCT. Salvage chemotherapy was decided case by case and clinical response was determined by functional imaging prior to ASCT. HT-TLI delivered 12 Gy in 3 daily fractions, by a dedicated setup, to all the body nodal chain with regards to the tumor burden area. HDC consisted of high-dose Bendamustine (400 mg/sqm) and Melphalan 140 (mg/sqm) for patients older than 40 years (n=10) and conventional FEAM (Fotemustine, Ethoposide, Cytarabine and Melphalan) for younger patients. Results Salvage chemotherapy induced complete response (CR) in 7 patients (5 HL, 2 NHL), partial response (PR) in 5 (2 HL,3 NHL), less than partial response (LPR) 3. Conditioning strategy was well tolerated. Six patients (40 %) experienced fever of unknown origin and 5 patients (33%) developed grade 3/4 mucositis. None experienced grade 3/4 extra-hematological toxicity. All patients showed complete engraftment and median time to neutrophil and platelet recovery was 11 (range 9-21) and 12 days (range 9-21) respectively. Median follow-up was 38 months (CI 95%: 1.3–66.1 months). All patients in PR or less before transplant achieved CR. There were no cases of treatment-related death. The 3-year overall PFS and OS were 78% and 93% (Fig. 1) respectively. Post-ASCT relapse occurred in 3 patients (HL=2 and NHL=1) at a median time of 8 months and 1 NHL patient subsequently died of progressive disease 7 months after ASCT. Conclusion Our preliminary results show that HT-TLI can be safely used in advanced lymphomas with sequential high dose chemotherapy as combined conditioning. With the limit deriving from the small size of this series, we observe that all patients achieved CR after the procedure, even if heavily pretreated, and that relapse rate was low. Overall these results encourage the implementation of HT-TLI in the standard conditioning for R/R lymphomas. PV-0367 TMLI-based low-toxic myeloablative conditioning regimen in haploidentical HSCT for AML C. Aristei 1 , V. Lancellotta 1 , A. Carotti 2 , C. Zucchetti 3 , S. Saldi 4 , A. Pierini 2 , L. Ruggeri 2 , S. Piccinini 2 , L. Amico 2 , M. Iacco 3 , A. Velardi 2 , M.F. Martelli 2 1 Radiation Oncology Section- University of Perugia and Perugia General Hospital, Surgery and Biomedical Sciences, Perugia, Italy ; 2 Division of Hematology and Clinical Immunology and Bone Marrow Transplant Program- University of Perugia and Perugia General Hospital, Medicine, Perugia, Italy ; 3 Medical Physics Unit- Perugia General Hospital, Medical Physics, Perugia, Italy ; 4 Radiation Oncology Section- Perugia General Hospital, Surgery and Biomedical Sciences, Perugia, Italy Purpose or Objective Hematopoietic stem cell transplantation (HSCT) is elective post-remission treatment for patients with intermediate- high risk acute myeloid leukemia (AML). The best donor is the matched sibling which is available for 25% of cases. The 1-haplotype mismatched relative (haploidentical) is a valid alternative as it is immediately available for 95% patients. In haploidentical HSCT total body irradiation is an essential component of the myeloablative conditioning regimen which, in elderly or young unfit patients, is associated with high toxicity and non-relapse mortality rates. In order to reduce the treatment-related toxicity we designed a conditioning regimen with total marrow/lymphoid irradiation (TMLI) and low chemotherapy doses. Furthermore, to induce a Graft versus Leukemia (G v L) effect with a low incidence of Graft versus Host Disease (G v HD) the graft contained, as

Conclusion Our study shows that the optimization of the treatment plan to the PRV volumes of CA located in the proximity of the target volumes ensures a significant reduction (ranging from 15 to 20%) of the mean and maximal dose received by the coronary tree. We thus recommend to integrate PRVs in the optimization process of mediastinal RT for lymphoma patients because they decrease the dose received by CA and may potentially limit the risk of long term ischemic complications. PV-0366 Helical Total Lymphoid Irradiation: radiotherapy still works in lymphoma transplantation S. Vagge 1 , F. Guolo 2 , A. Dominietto 3 , S. Agostinelli 4 , M. Gusinu 4 , A. Ibatici 3 , F. Ballerini 2 , R.M. Lemoli 2 , E. Angelucci 3 , M. Gobbi 2 , R. Corvò 5 1 IRCCS Ospedale Policlinico San Martino- academic hospital, Radiation Oncology, Genova, Italy; 2 IRCCS Ospedale Policlinico San Martino, Clinica Ematologica, Genova, Italy; 3 IRCCS Ospedale Policlinico San Martino, Ematologia, Genova, Italy; 4 IRCCS Ospedale Policlinico San Martino, Medical Physics, Genova, Italy ; 5 IRCCS Ospedale Policlinico San Martino, Radiation Oncology, Genova, Italy Purpose or Objective Assessing feasibility and preliminary outcomes of a conditioning strategy based on high dose chemotherapy (HDC) and Helical Total Lymphoid Irradiation (HT-TLI) as preparation for autologous stem cell transplantation (ASCT) in patients affected by relapsed/refractory (R/R) Hodgkin’s Lymphoma (HL) and non-Hodgkin lymphoma (NHL). Salvage chemotherapy followed by ASCT is the standard of care for patients with R/R. However conventional conditioning regimens have low efficacy in R/R patient and only a minority of them is cured by this approach. Promising results with a technical “old suite” total lymphoid irradiation (TLI) and with hyperfractionated schedules, followed by high-dose chemotherapy and ASCT have been reported in advanced HL patients, despite relevant toxicity due to radiation- induced damage of healthy tissues. Material and Methods