Abstract Book

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ESTRO 37

Material and Methods From 2003 to 2016, 438pt with EC were treated with PRT and divided into 3 age groups: Group-1: 202pt <65 years(y); Group-2: 210p≥65y and <80y; Group-3: 26pt≥80y. Vaginal toxicity was assessed using the objective LENT- SOMA criteria and RTOG scores were recorded for the rectum, bladder and small bowel. Statistics: Chi-square and Students’s t-tests, Kaplan-Meier analysis for CSS. Results Mean follow-up: Group-1: 5.6y, Group-2: 5.6y, Group-3: 6.3y (p=0.38). No differences were found among the groups in distribution of stage, grade, myometrial invasion, Type 1 vs. 2 EC and VLSI (p=0.97, P=0.52, p=0.35, p=0.48, p=0.76 respectively). There were no differences in rectal, bladder and vagina late toxicity (p=0.46, p=0.17, p=0.75 respectively). Better CSS at 5y was found in Group-1 (p= 65 0.006) and significant differences were found in late severe small bowel toxicity in Group-3 (p=0.005). Conclusion Patients ≥65y had a worse outcome in comparison to younger. Late vaginal, rectal and bladder toxicities were similar in the 3 groups; although an increase of severe late small bowel toxicity led to IMRT in age ≥80y. Larger studies are needed including quality of life analysis in pt ≥80y. GRANT: SPANISH ASSOCIATION AGAINST CANCER (AECC) P. Castelnau-Marchand 1 , P. Pautier 2 , C. Genestie 3 , A. Leary 2 , E. Bentivegna 4 , S. Gouy 4 , J.Y. Scoazec 3 , P. Morice 4 , C. Haie-Meder 1 , C. Chargari 5 1 Gustave Roussy, Brachytherapy Unit- Radiation Oncology, Villejuif, France 2 Gustave Roussy, Department of Medical Oncology, Villejuif, France 3 Gustave Roussy, Department of Pathology, Villejuif, France 4 Gustave Roussy, Department of Surgery, Villejuif, France 5 Gustave Roussy, Brachytherapy Unit- Radiation Oncology- French Military Health Services Academy- Institut de Recherche Biomédicale des Armées, Villejuif, France Purpose or Objective The purpose of our study is report our institutional experience of a multimodal approach for treatment of locally advanced high grade neuroendocrine cervical cancer (NECC). Material and Methods Patients with primary locally advanced NECC diagnosed between 2001 and 2014 were included. The scheduled treatment sequence was as follows: pelvic with or without para-aortic radiotherapy (depending on the primary staging), associated with chemotherapy based on platine-derivate and etoposide (EP) regimen, followed with a brachytherapy boost, then completion surgery if no progression with or without consolidation EP chemotherapy (in order to deliver a total of 5-6 cycles). Disease free survival (DFS) and overall survival (OS) were reported, and prognostic factors were searched. Results A total of 24 patients fulfilled inclusion criteria. Median age was 48 years (range 22-77 years). Fourteen (58%) patients had pelvic lymph node metastases. After chemoradiation/brachytherapy, a radical hysterectomy EP-1505 Multimodal management of locally advanced neuroendocrine cervical carcinoma

could be performed in 18/24 (75%) patients. Histologically complete resection was achieved in 14/18 (78%). Complete pathological response was seen in 7/18 (39%). Residual tumor in hysterectomy specimen was found in 11/18 (61%). With median follow-up of 29.7 months. Of all, 10/24 (42%) patients had tumor relapse, all associated with distant failure, and including one local failure. Three-year estimated disease-free survival and overall survival were 55% and 63%, respectively. Lymph node metastases and tumor stage were prognostic for DFS (p=0.016 and p=0.022, respectively). Complete resection was associated with a lower incidence of relapses, as compared with microscopically incomplete resection (p=0.04). Twelve (86%) patients with negative margins were in complete remission at last follow-up. Apart of manageable acute hematological toxicities, most treatment complications were mild to moderate. Conclusion This series based on a multimodal management compares favorably to previously published data. Most patients could be eligible to surgery, and complete remission was achieved in 85% of those with complete resection. EP-1506 Simultaneous integrated nodal boost in cervical cancer: acute toxicity and treatment compliance W. Bacorro 1,2 , N. Manea 1 , I. Dumas 3 , S. Gouy 4 , E. Bentivegna 4 , P. Morice 4 , E. Deutsch 1 , C. Haie-Meder 1 , C. Chargari 1 1 Gustave Roussy Institute, Radiation Oncology, Villejuif, France 2 Benavides Cancer Institute, Radiation Oncology, Manila, Philippines 3 Gustave Roussy Institute, Medical Physics, Villejuif, France 4 Gustave Roussy Institute, Surgery, Villejuif, France Purpose or Objective We report our experience on the use of simultaneous integrated nodal boost (SINB) in cervical cancer, in terms of OAR doses, acute toxicity and treatment compliance. Secondarily, we report medium-term toxicity, control and survival rates. Material and Methods From 2014-2016, 40 patients with N1M0 cervical cancer (para-aortic, PA, involvement below L1-L2 included) underwent concurrent chemoradiation (CRT) with SINB followed by pulsed-dose rate image-guided adaptive brachytherapy (IGABT). Staging included pelvic MRI, PET and, in case of PA node- negative PET, PA dissection. The pelvis ± PA ± inguinal (ING) was treated to 45Gy in 25 fractions, using IMRT (tomotherapy) techniques. With the expected IGABT contribution considered, SINB doses (Gy) were: ING, 55.7; lower pelvis (LP)(obturator, internal and external iliac), 55.0-57.5; upper pelvis (UP)(common iliac), 57.5; and PA, 60.0. Acute toxicity was monitored weekly during CRT. Late toxicity and disease status were monitored every 3-6 months after treatment. Results Median age was 49 years (range 25-74). Histology was squamous carcinoma in 88% and adenocarcinoma in 13%. FIGO stage distribution was as follows: IB, 13%; IIA, 5%; IIB, 55%; IIIA, 10%; IIIB, 13%; IVA, 5%. EBRT included the PA in 25%; ING, 5%; and PA + ING, 3%. SINB was to the LP only in 50%; UP only, 3%; LP + UP, 30%; LP + UP + PA, 15%; and LP + UP + ING, 3%. Cisplatin was given in 90%, carboplatin in 10%.