ESTRO 37 Abstract book

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ESTRO 37

4 Radiotherapy Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II", Campobasso, Italy 5 Medical Physics Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II”, Campobasso, Italy 6 Radiology Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II”, Campobasso, Italy 7 Radiation Oncology Unit, Bellaria Hospital, Bologna, Italy Purpose or Objective Whole brain radiation therapy (WBRT) is an effective therapeutic modality in patient with brain metastases. However, nearly 90 % of patients undergoing WBRT suffer from neuro-cognitive function (NCF) impairment at the diagnosis and up to two-thirds will experience a further decline within 2 to 6 months after WBRT. Focal dose reduction on bilateral hippocampus is thought to improve NCF preservation. Aim of the present study is to present a systematic review of clinical results on NCF after HS- WBRT. Material and Methods A systematic review of published literature was performed on PubMed and the Cochrane Library. Only prospective clinical trials reporting NCF outcome of patients treated with hippocampal sparing (HS)-WBRT have been analyzed. Results A total of 165 patients from 3 studies were included. The studies are characterized by small sample size and different methods in term of radiotherapy technique, but with similar planning results and NCF assessment tests. No significant changes in NCF (i.e., verbal and non-verbal learning memory, executive functions, and psychomotor speed) between baseline and 4 month-follow-up after RT or only a mean relative decline in delayed recall to 4 months (7%), significantly lower in comparison with historical control (30%), were observed. Conclusion HS-WBRT is a feasible technique, able to provide highly conformal and homogenous dose distributions for the whole brain planned target volume with lower doses to organ at risk such as the hippocampus. Considering the safety profile of HS-WBRT and preliminary results on NCF preservation, further studies appear justified in patients undergoing brain irradiation for brain metastases. EP-1190 Vitamin D Levels In Blood And Survival In Glioblastoma M.A. Berenguer Francés 1 , I. Linares 1 , S. Almendros 1 , I. Guix 1 , A. Navarro 1 , S. Comas 1 , M. Maciá 1 , A. Lucas 1 , F. Guedea 1 1 Instituto Catalan De Oncologia, Radiation Oncology, Hospitalet De Llobregat, Spain Purpose or Objective Vitamin D has antitumor functions in the body. 1,25(OH) 2 D 3 (calcitriol) functions can be divided into two groups, one of endocrine nature implied in the bone biology regulation and other recently discovered with paracrine and autocrine character, holding immunomodulatory capacity. The immunomodulatory effect of calcitriol was discovered in 2010 and is based on the innate immunity enhancement and the adaptive immunity inhibition. This effect is noted through several mediators including the tumor hypoxia factor HIF-1 or the increase of the E-cadherin involved in the epithelial- mesenchymal transition (EMT), observing a decrease in the inflammatory effect, cellular proliferation, metastasis and angiogenesis, also with an increase of cellular apoptosis. Material and Methods Had we retrospectively analyzed patients blood vitamin D levels in patients diagnosed of glioblastoma (GM) at our institution.

Vitamin D levels were studied prior to the start of the chemotherapeutic and radiotherapeutic treatment in 32 patients (17 males and 15 females) with an average age of 59 years (36-76) diagnosed with GM. 6 of the 32 patients (18.8%) had IDH1 mutation and the rest were IDHwt (81.3%). 18 patients (56.3%) presented values higher than 30 ng/ml while 14 patients (43.8%) had lower values. Median progression free survival was 5,14 months in lower values and 12,24 months in values higher than 30 ng/ml (p=0.000). Results

Overall survival was 7.38 month in group with low values of vitamin D and 18.11 months in group with high values of vitamin D (p=0.000) Patients with high levels of calcidiol had a greater pseudoprogression effect as evidenced by MR with spectroscopy in the first radiographic control (p=0.029). Kaplan-Meier and multivariable modeling revealed that IDH mutations was a predictive factor for improved survival (p=0.004). There were no differences in tolerance to treatment, in sex, in the type of surgical intervention or in the location of the lesion. Conclusion Vitamin D deficienciy might be a potential therapeutic target in glioblastoma. However, additional studies are needed to establish optimal serum levels for patients with glioblastoma. EP-1191 Outcomes of a mono-institutional experience of IG-IMRT in Glioblastoma A.M. Deli 1 , F. Zerbetto 1 , A. Fodor 1 , C.L. Deantoni 1 , N. Slim 1 , I. Dell'Oca 1 , C. Gumina 1 , G. Rossi 1 , S. Foti 1 , S. Broggi 2 , P. Mangili 2 , A. Bolognesi 1 , N.G. Di Muzio 1 1 San Raffaele Scientific Institute, Radiotherapy, Milan, Italy 2 San Raffaele Scientific Institute, Medical Physics, Milan, Italy Purpose or Objective To report outcomes of patients(pts) with newly diagnosed glioblastoma(GBM) treated with radical/adjuvant Image- Guided Intensity Modulated Radiotherap (IG-IMRT) at a single institution. Material and Methods From 02/2013-02/2016, 90 GBM pts and a median age of 60.2(33.0-79.1) years, were treated with IG-IMRT in our institution. One lesion was diagnosed in 78% of pts, while in 22% was multifocal GBM. Surgery was performed in 62.2%, biopsy in 33.3% of pts, respectively; in 4.5% of pts, the diagnosis was based on MRI characteristics. Concomitant and adjuvant chemotherapy(CT) was prescribed in 72% of pts; 62% of pts had an adjuvant IG- IMRT, while 38% a radical IG-IMRT. Median GTV was 48.9(10.2- 340.5) cc. A total dose(TD) of 60 Gy /30 fr was prescribed in 66 pts, and 40 Gy/15 fr(Roa’s protocol) in 22 pts; in two pts, the TD prescribed was 50.4 and 53.4 Gy, respectively, because of tumor position and PTV volume. GTV definition was based on contrast-enhanced MRI in all pts. The treatment was delivered with helical IMRT in 59% of pts and with volumetric IMRT in 41% of pts. Image guidance (kVCT/MVCT) was performed daily in

all pts. Results

With a median follow-up of 10.9(0-47.5) months, 7 pts were alive at the last follow-up. Median OS was 17.0(0.9-