ESTRO 38 Abstract book

S62 ESTRO 38

molecular and clinico-pathologic features were found to have a higher prognostic accuracy than either alone. This concept has been carried forward in the on-going randomised PORTEC-4a trial that investigates molecular profile-based versus standard recommendations for adjuvant therapy, with the overall aim is to further decrease both over- and undertreatment in early stage endometrial cancer. SP-0123 Improving outcomes in high-risk locally advanced cervical cancer: extended field RT, adjuvant chemotherapy or immunotherapy? C. Chargari 1 , C. Haie-Meder 1 , S. Gouy 1 , E. Deutsch 1 1 Institut Gustave Roussy, Radiation Oncology, Villejuif, France Abstract text The implementation of image guided adaptive brachytherapy has allowed achieving very high local control rates in locally advanced cervical cancer patients. However, a threshold seems to have been achieved in terms of survival, which remains alleviated by a high frequency of distant relapses, justifying the development of novel strategies aimed at further improving patients outcome. Conventional approaches are being tested, based on neoadjuvant or adjuvant combinatory chemotherapy. Another strategy relies on the better identification of patients warranting para-aortic irradiation, either through integration of primary para- aortic lymph node dissection or by inclusion of high-tech imaging modalities to better guided treatment fields. An adapted approach has also been proposed to tailor radiotherapy fields for each patient according to conventional risk factors, mainly based on the tumor stage. Finally, the increasing knowledge of tumor biology and the rapidly evolving field of anti-tumor immunity encourage pharmacological approaches in order to exploit the complex interplays between tumor and its microenvironment through radiotherapy. SP-0124 Chemo-radiation in Vulvar Cancer: recent developments in (neo)adjuvant and primary therapy S. Marnitz-Schulze 1 1 University Clinic Cologne, Radiation Oncology, Cologne, Germany Abstract text Chemoradiation in vulvar cancer patients is used postoperatively as adjuvant treatment for patients on high risk for recurrence, in a neoadjuvant setting with the aim to avoid mutilative surgery in patients with locally advanced disease and as a primary treatment to avoid surgery at all. In the recent years there has been a shift to more HPV-positive tumors, younger patients and those with unfavourable tumor localizations. Sentinel node technique has become a standard procedure for inguinal lymph node staging. The use of Sentinel technique lead to a dramatic decrease of morbidity like wound break down and lymph edema compared to full lymphadenectomy and also decreased the treatment related toxicity after radiation. Concerning the optimal diagnostic tool and treatment of pelvic and or para-aortic lymph node metastases, no internationally accepted standard has been established. In contrast to cervical cancer, no data are avaiable with regard to the optimal radiation sensitizer. The talk discusses the data for pre-therapeutic lymph node staging with tailored chemoradiation concepts and the PROs and CONs of (neo-)adjuvant versus primary chemo-radiation, different drugs, dose and target concepts for contemporary treatment of vulvar cancer patients.

(pelvis vs remote for lymph nodes; para-spinal vs rest for bones). SP-0120 What is the optimal target volume concept in radiotherapy for oligometastatic pelvic lymph nodes after radical prostatectomy? T. Zilli 1 1 Hôpitaux Universitaires de Genève, Radiation Oncology, Geneva, Switzerland Abstract text After radical prostatectomy, up to one third of the patients recur mainly with nodal lesions located in the pelvis. Radiation therapy (RT) has been demonstrated to be an effective salvage treatment for oligorecurrent (≤ 5 metastases) prostate cancer, with promising results is in terms of disease control and low treatment related toxicity. Both stereotactic body RT (SBRT) and elective nodal RT are been used in this setting and are considered valid, even if still investigational, treatment options. However, the best way to irradiate patients with an exclusive oligorecurrent nodal disease remains debated with many open questions on the performance of imaging techniques in reliably detect the recurrent disease. The aim of this talk is to discuss the rationale supporting the two different approaches (focal versus elective) for oligorecurrent nodal prostate cancer, and to present recent results and ongoing trials that will support the different treatment options. SP-0121 What is the optimal sequencing of local and systemic treatment in oligometastatic prostate cancer? G.De Meerleer 1, 2 1 University Hospitals Leuven, Department of Radiation Oncology, Leuven, Belgium; 2 KU Leuven, Department of Oncology, Leuven, Belgium SP-0122 Integration of molecular prognostic factors in the management of endometrial cancer R.Nout 1 1 Leiden University Medical Center LUMC,Department of Radiotherapy, Leiden, The Netherlands Abstract text The majority of endometrial cancer (EC) patients present at an early stage (80% FIGO stage I) and have a good prognosis (overall survival stage I: 85%). Total hysterectomy and salpingo-oophorectmy is the mainstay of treatment. Clinicopathological risk factors (e.g. grade, depth of myometrial invasion, presence of LVSI) are currently used in clinical practice to help identify patients who may benefit from adjuvant (postoperative) therapy. More recently the TCGA group comprehensively assessed molecular alterations in endometrial cancer and found four groups with distinct prognosis: POLE -mutant ultramutated, MSI hypermutated, p53-mutant copy- number high (serous like), and a copy number low group without a specific mutation. The POLE -mutant group had a very low risk of recurrence despite their ultramutated phenotype and the p53 mutant group had an increased risk of disease progression. Subsequent studies have confirmed the distinct prognostic impact of these four groups, and have identified additional (targetable) prognostic molecular markers. In addition to these molecular features analysis of the impact of grading of LVSI pointed out that substantial LVSI in contrast to no or mild LVSI was a strong independent risk factor for regional and distant recurrence. Furthermore, risk groups based on combined Abstract not received Symposium: New developments in gynaecological cancers