ESTRO 38 Abstract book

S810 ESTRO 38

minimal limitations of daily activities. Parameters related to bladder function may be negatively affected by bladder V40 and V35. EP-1495 Improved Disease-Free Survival with Radiotherapy in Early Stage Endometrial Cancer: 10- year outcome S. Aytac Arslan 1 , I.P. Aral 2 , G. Altinisik Inan 1 , Y. Tezcan 1 , F. Avsar 3 , Y. Guney 4 1 Yildirim Beyazit University, Radiation Oncology, Ankara, Turkey ; 2 Elazığ Fethi Sekin Şehir Hospital, Radiation Oncology, Elazığ, Turkey ; 3 Yildirim Beyazit University, Obtetric and Gynecology, Ankara, Turkey ; 4 Ankara Memorial Hospital, Radiation Oncology, Ankara, Turkey Purpose or Objective The aim of this study is to evaluate the long term treatment outcomes of patients with early stage The data of 311 patients from 2 institutions with the international federation of gynecology and obstetrics (FIGO) stage 1-2 endometrial cancer whom received ±adjuvant treatment following surgery between June 2001 and December 2016 were retrospectively reviewed. Of these, 74 (24%) received no further treatment, 4 (1%) received only chemotherapy (CT), 233 (75%) received radiotherapy (RT) and 24 (7%) received both. RT was administrated as pelvic + vaginal brachytherapy (n=128, 54.2%) or vaginal brachytherapy (n=106, 45.8%). Results The median follow-up was 102 months (range, 3 to 205 months). During this period, 68 (22%) patients died; of which 41 were disease related. Ten-year disease-free survival (DFS) and disease specific survival (DSS) were 73.9% and 82.7% respectively. The univariate analysis showed that nonendometrioid pathology, lymphovascular invasion (LVI) positivity, grad 3 histology, myometrial invasion ³1/2, cervical stromal invasion (stage 2) and no adjuvant RT had negative significant impact on DSS. Cox multivariate analysis revealed that LVI (p:0.010, HR:2.96, CI:1.5-5.7) and stage (p:0.018, HR:2.1, CI:1.1-4) for DSS; RT (p:0.032, HR: 0.49, CI:0.2-0.9), LVI (p:0.02, HR:1.8, CI:1.09-3.1) and stage (p:0.04, HR: 1.8, CI:1.002-3.15) for DFS are as independent prognostic factors. Conclusion The findings of our cohort have affirmed the importance of adjuvant RT as a previously identified prognostic variable on long term early-stage endometrial carcinoma progression. RT can be suggested to LVI positive early stage endometrial carcinoma patients even without any other risk factors. EP-1496 Feasibility of carbon ion radiotherapy for the melanoma of the lower genital tract A. Barcellini 1 , V. Vitolo 1 , M.R. Fiore 1 , A. Iannalfi 1 , endometrial carcinoma. Material and Methods

European Institute of Oncology- Milan- Italy, Radiation Oncology, Pavia, Italy

Purpose or Objective Malignant mucosal melanoma (MMM) of the female genital tract is a rare and aggressive disease with a 5-years overall survival of 37-50% for vulvar (VuM), 13-32% for vaginal (VaM) and 10% for cervical melanoma (CM). MMM has been regarded as radioresistant tumors demonstrating unsatisfactory local control after photon radiotherapy. Based on the promising previous Japanese experience and in light of the well-known biological and therapeutic advantages of carbon ion radiotherapy (CIRT), we were prompted to use CIRT for gynecological MMM. The aim of the present study is to report our preliminary experience with CIRT in the treatment of gynecological MMM at the National Center of Oncological Between January 2016 and September 2018, 8 patients were admitted for CIRT at CNAO. Patient median age was 65 (range: 52-83). They had 6 VaM, 1 CM and 1 VuM. One patient with VaM had been previously irradiated with photons. GTV ranged from 1.13 to 380.96 cm3 (median: 28.01 cm3). Two patients underwent to neoadjuvant and sequential anti-PD-1 immunotherapy. Due to their huge macroscopic diseases, the CM and VuM patients were irradiated with up to a total dose of 28 GyRBE in 3 fractions and 68.8 GyRBE in 16 fractions, respectively, and the CTV was defined as the GTV + uterine cervix and corpus for the CM and GTV + vulva for the VuM.Except one case, in the VaM the small pelvic space including GTV was irradiated with up to a total dose of 43 GyRBE (in 10 fractions) followed by a GTV boost of up to a total dose of 68.8 GyRBE in 16 fractions. One patient underwent to adjuvant CIRT on the small pelvic space up to a dose of 43 GyRBE after a radical surgery without lymphadenectomy. Acute and late toxicities were scored according CTCAE 4.0 scale. Time to event data was calculated from the end of CIRT. Results The treatment was well tolerated and no interruption was needed. During and at the end of CIRT only a patient experienced G3 erythema and 4 patients grade G1 vaginitis. For the evaluable patients (4) the median local control was 10.23 months for VaM and 7.26 months for CM. All these 4 patients experienced systemic progression. Data is still ongoing for the latest enrolled patients. Conclusion Because of the low incidence, there are no established guidelines for the management of gynecological MMM. Even if extensive surgery, when feasible, is the standard treatment due to high rate of distant metastases and unsatisfactory survival benefit, more conservative treatment approaches may be warranted. MMM is a radioresistant tumor, an ideal disease to test the biological efficacy of CIRT. Our preliminary results are encouraging, but a longer follow-up and large patient accrual are required. Patients should be encouraged to participate in clinical trials. EP-1497 Particle radiotherapy for re-irradiation of pelvic recurrences of gynecological cancer A. Barcellini 1 , V. Vitolo 1 , R. Lazzari 2 , M.R. Fiore 1 , A. Iannalfi 1 , B. Vischioni 1 , A. Facoetti 3 , S. Ronchi 1 , M. Bonora 1 , E. D'Ippolito 1 , R. Petrucci 1 , A. Mirandola 4 , A. Vai 4 , E. Mastella 4 , S. Russo 4 , G. Viselner 1 , M. Ciocca 4 , L. Preda 5 , F. Valvo 1 , R. Orecchia 6 1 National Centre of Oncological Hadrontherapy CNAO, Radiation Oncology, Pavia, Italy ; 2 European Institute of Oncology, Radiation Oncology, Milano, Italy ; 3 National Centre of Oncological Hadrontherapy CNAO, Radiobiology, Pavia, Italy ; 4 National Centre of Oncological Hadrontherapy CNAO, Department of Hadrontherapy (CNAO). Material and Methods

B. Vischioni 1 , P. Fossati 1 , S. Ronchi 1 , M. Bonora 1 , E. D'Ippolito 1 , R. Petrucci 1 , A.

Facoetti 2 , A. Mirandola 3 , A. Vai 3 , S. Molinelli 3 , E. Mastella 3 , S. Russo 3 , G. Viselner 1 , L. Preda 4 , M. Ciocca 1 , F. Valvo 1 , R. Orecchia 5 1 National Centre of Oncological Hadrontherapy CNAO, Radiation Oncology, Pavia, Italy ; 2 National Centre of Oncological Hadrontherapy CNAO, Radiobiology, Pavia, Italy ; 3 National Centre of Oncological Hadrontherapy CNAO, Department of Medical Physics, Pavia, Italy ; 4 National Centre of Oncological Hadrontherapy CNAO- University of Pavia- Pavia- Italy, Department of Clinical-Surgical- Diagnostic and Pediatric Sciences, Pavia, Italy ; 5 National Centre of Oncological Hadrontherapy CNAO-