ESTRO 2020 Abstract Book

S590 ESTRO 2020

radioactive source projectors, but the remaining centers referred their patients outside for BT. Magnetic resonance was performed in >95% centers in early CC (ECC) and in locally advanced CC (LACC) settings, while positron emission tomography combined with computed tomography (PET-CT) scan was preferred in LACC patients (93.3%). ECC post-surgery treatment was performed in 96.7% of cases following the pathologically assessed high risk factors. Locally advanced CC treatment was exclusive chemoradiation in 84.4% of centers, with concomitant chemotherapy mostly represented by platinum-based schedule. Others different LACC approaches were reported in a variable rate (4.4%-28.9%). In the oligo-metastatic or recurrent setting 74.4% and 53.3% centers declared to have managed <5 recurrences post-surgery and post-irradiation, respectively. Chemotherapy was frequently proposed (Carboplatin- Taxol q21: 67.9%, or CDDP-Taxol q21: 19.2%). Conclusion The present survey report a broad spectrum of opinions and clinical pathways in the clinical CC treatment in Italy. Availability and use of modern techniques is quite good, but a more wide distribution of brachytherapy resources and skills still remains a challenge for the future. PO-1117 Two-step adaptive 3-D conformal brachytherapy for advanced bulky cervical cancer I.J. Cho 1 , Y. Kim 1 , J. Jeong 1 , W. Chung 1 , S. Ahn 1 , T. Nam 1 , J. Song 1 , S. Cho 1 , M.S. Yoon 1 1 Chonnam National University Hwasun Hospital, Radiation Oncology, Hwasun-gun, Korea Republic of Purpose or Objective The role of adaptive conformal brachytherapy (ACB) in advanced bulky cervical cancer has not yet been determined. We evaluated feasibility and efficacy of two- step ACB to investigate whether reduced dwell time during brachytherapy (BT) based on tumor regression confers a benefit for delivering effective dose to high-risk clinical target volume (HR-CTV) with better local control. Material and Methods Two-step ACB were performed during brachytherapy in patients with >5 cm bulky cervical cancer. All patients received 3-D conformal external beam radiation therapy (EBRT) with concurrent cisplatin. Consecutive MRI were performed pre-radiotherapy, pre-BT and during interfraction of BT. Two-step ACB consisted of three channel with tandem and ovoid applicator following reduced 192 Ir dwell position to the regressed tumor with or without a cervical cylinder applicator. Two-step ACB was composed of several 5Gy fractions following with interim BT modification consisting of a few fractions of less than 5 Gy to point A. Results Fifty consecutive patients with >5cm FIGO stage IB2-IVA cervical cancer completed radiotherapy with concurrent weekly cisplatin from 2013 to 2016. Of patients, 90% received median EQD2 (α/β=10) 25Gy of first step ACB (range, 6.25-39.32) to whole uterus after median 45 Gy EBRT to whole pelvis. After second step ACB to HR-CTV, the cumulative median EQD2 (α/β=10) to point A was 84.66 Gy (64.71-126.32) with median total fraction of 8. The 3-year local control rates was 94%. No severe genitourinary and gastrointestinal acute toxicity was observed. Late toxicity of hematuria requiring transfusion occurred in 2 patients. Grade 3 and 4 late gastrointestinal late toxicity was observed in 7 and 1 patients, respectively. Actuarial overall and disease-free survival at 3 years was 80% and 63%, respectively. Conclusion Two-step adaptive conformal brachytherapy showed excellent local control with comparable toxicity for bulky cervical cancer. Using interim BT modification according to regressed cervical tumor, two-step ACB and 3-D EBRT is feasible in patients with >5cm bulky cervical cancer with

Conclusion The TRG is confirmed as a fundamental parameter in determining the outcomes in patients with rectal cancer subjected to NA-CRT. A prospect still open for the future is the integration of the TRG in the staging of the patient to identify the classes of patients at risk and worthy of adjuvant therapy.

Poster: Clinical track: Gynaecological (endometrium, cervix, vagina, vulva)

PO-1116 Cervical cancer patterns of care in italy: a radiation oncology survey of mito and airo gyn groups G. Macchia 1 , A. Cerrotta 2 , F. Deodato 1 , B. Pappalardi 2 , A. Re 1 , R. Santoni 3 , M. Campitelli 4 , G. Scambia 5 , V. Valentini 6 , C. Aristei 7 , G. Ferrandina 5 1 Fondazione Giovanni Paolo II- Università Cattolica S. Cuore, Radiotherapy Unit, Campobasso, Italy ; 2 Fondazione IRCCS Istituto Nazionale dei Tumori, Radiotherapy Unit, Milan, Italy ; 3 University of Rome Tor Vergata- UNIROMA2, Radiotherapy Unit- Department of Biomedicine and Prevention, Roma, Italy ; 4 Fondazione Policlinico Universitario A. Gemelli IRCCS-, UOC di Radioterapia- Dipartimento di Scienze Radiologiche- Radioterapiche ed Ematologiche, Roma, Italy ; 5 Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC Ginecologia Oncologica- Dipartimento per la Salute della Donna e del Bambino e della Salute Pubblica, Roma, Italy ; 6 Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radioterapia- Dipartimento di Scienze Radiologiche- Radioterapiche ed Ematologiche, Roma, Italy ; 7 University of Perugia and Perugia General Hospital, Radiation Oncology Section, Perugia, Italy A not negligible heterogeneity of treatments options in Cervix cancer (CC) clinical settings was documented, despite the WHO has encouraged to adopt treatments based on high level of evidence. A national survey on the current patterns of care in every clinical setting of CC patients was set up in order to identify possible causes of variations from guidelines, and set up more effective educational efforts thus allowing optimization of treatments, and ultimately improving patient care. Material and Methods A questionnaire concerning CC management, focusing on demographic aspects, practice settings and equipment, was distributed online via SurveyMonkey to radiation oncologists. Results Ninety questionnaires, accounting for 46.3% of the 194 Italian radiotherapy centers were returned. The majority of respondents practiced at national community hospitals, with dedicated multidisciplinary tumor board (87.8%), modern equipment and techniques. Concerning brachytherapy (BT), 55.5% of centers reported >1 Purpose or Objective Background