ESTRO 36 Abstract Book

S614 ESTRO 36 2017 _______________________________________________________________________________________________

1 ASST Papa Giovanni XXIII, Radiation Oncology, Bergamo, Italy 2 ASST Papa Giovanni XXIII, Medical Physics, Bergamo, Italy Purpose or Objective Sezary syndrome(SS) is a rare erythrodermic and leukemic variant of cutaneous T cell lymphomas(CTCL) that belongs to extranodal non-Hodgkin’s lymphomas. SS together with mycosis fungoides (MF) are the most common forms of CTCL.SS has an aggressive behavior with a median survival of 1–5 years.In CTCL nervous system involvement has been reported in 1.6% of patients. Most patients had a MF with malignant transformation and usually it is associated with late stage disease and very poor prognosis. Individual case reports of patients with large cell trasformation of MF but not of SS, were described.We report a case of histologically proven meningeal involvement in a patient with early stage SS treated with craniospinal irradiation with Volumetric Modulated Arc Therapy(VMAT) technique with long term radiologic complete response, alive 5 years after diagnosis. Material and Methods Case report. A 67-year-old woman with a Sezary Syndrome diagnosed 3 years before, with a 3 months history of headache, underwent a cranial magnetic resonance imaging (MRI) showing diffuse meningeal contrast enhancement with thickening, especially in frontal meninx. A biopsy was performed with diagnosis of meningeal localisation of T cell lymphoma.She underwent intratechal chemotherapy with radiologic stable disease, so a craniospinal irradiation with VMAT technique was performed. Prescription dose was 18 Gy on entire neuraxis in 10 fractions (1.8 Gy per fraction) and a 6 Gy sequential boost in 3 fractions on the brain(total dose 24 Gy). Treatment was performed in supine position with a head long mask and a vacuum pillow including body till pelvis. PTV length was 70 cm. Three isocenters were used. Distance between cranial and thoracic isocenters and between thoracic and abdominal isocenters was 23 cm. Plan was optimised defining an overlapping region between arcs of different isocenters so that no field matching was necessary. Set-up position verification by daily CBCT was performed. Results Headache resolution was observed before the end of radiation treatment. No toxicity was reported.The first MRI performed 1 month after the completion of radiotherapy showed a partial response and after 6 months, a complete radiologic response was achieved. At present , with a 17 months follow-up, she is still in clinical and radiological complete remission with good performance status and quality of life. Conclusion This is the first reported case of meningeal metastasis in SS patients. In contrast with previous reports, our patient didn't present with advanced or aggressive disease. Our report reinforces the hypothesis of a possible neurotropism of malignant cells in MF and SS. CNS involvement could be evaluated in patients with unexplained neurologic symptoms or neuropathic pain, that are not unusual. Although a poor outcome is expected in these patients, we reported a long term complete response with impact on quality of life and survival with VMAT craniospinal irradiation. EP-1138 Dosimetric accuracy of linac based Total marrow Irradiation B. Aydogan 1 1 Univ. of Chicago Medical Center, Radiation and Cellular Oncology, Chicago, USA Purpose or Objective We are currently investigating the feasibility of adding linac based total marrow irradiation (TMI) with

Data were retrospectively analyzed. Survival was calculated from the diagnosis to the death date or last follow-up. Results Median follow-up was 28.5 months(range 23-76) . Eleven patients (79%) completed radiotherapy without breaks. One patient died during radiotherapy, one stops the treatment because of neurological deterioration and one for lack of compliance. Median survival from first diagnosis was 8.5 months (range 1-70). Median survival from the end of radiotherapy was 4 months(range 1-34). In patients older than 60 years (64%) median survival from diagnosis was 14 months and in patients younger than 60 years(36%) was 4 months. One of these patients, HIV- positive, died one month after the completion of radiotherapy. One-year survival rates from diagnosis was 46%, 2 years survival rate was 30% and 5 years survival rate was 7%. Fifty percent of patients had a radiologic or clinical progression. In 5 patients radiologic response was not assessed because of poor clinical conditions. Five/9 patients (55%) who underwent imaging evaluation had a response (33% complete and 22% partial). In 25% of patients an early improvement of neurological status during radiotherapy was reported. Conclusion Despite limitations due to the small number of patients, radiotherapy may represent a feasible option in patients with diagnosis of PCNSL that are unfit for chemotherapy or had recurrence or no response, with a quite good tolerance and survival in same cases. We have not observed worse tolerance or survival in older patients. EP-1136 Technical results of total skin irradiation using helical TomoTherapy. K. Okuma 1 , A. Haga 1 , Y. Imae 1 , W. Takahashi 1 , K. Nakagawa 1 1 University of Tokyo Hospital, Radiology, Tokyo, Japan Purpose or Objective The purpose of this study was to report results of dose distributions of total skin irradiation (TSI) for cutaneous T- cell lymphoma using helical TomoTherapy (Accuray, Sunnyvale, CA). Material and Methods In our institution, six patients with refractory T-cell lymphoma were tried to treat of TSI using TomoTherapy. Treatments were delivered to three parts of the body (legs, head and neck, and trunk). Patients were received a prescription dose of 10-20 Gy in 10 fractions over 14 days in each part. Results Five out of six patients, TomoTherapy technique was able to achieve good coverage of the planning target volume (PTV) and good sparing of organ at risk. In one patient who was a 25-year-old big man diagnosed mycosis fungoides, dose distribution of trunk, especially abdominal skin, were not able to achieve good coverage of PTV. The body mass index (BMI) of the patient was 30.6 while the mean BMI of other patients were 22 (18-25). However, a trial planning using another big patients’ CT (BMI=38) showed good dose Using helical TomoTherapy was a good new treatment technique for TSI. It was not able to get good coverage of PTV for all patients. This treatment method will be needed further research to get good dose distribution for all patients. EP-1137 Meningeal localisation in Sezary Syndrome patient treated with VMAT craniospinal irradiation R. MuniI 1 , M. Fortunato 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 distribution. Conclusion