ESTRO 36 Abstract Book

S591 ESTRO 36 2017 _______________________________________________________________________________________________

3 maria sklodowska-curie memorial cancer center and institute of oncology iii dept., center for translational research and molecular biology of cancer, gliwice, poland 4 maria sklodowska-curie memorial cancer center and institute of oncology iii dept., tumor pathology department, gliwice, poland 5 maria sklodowska-curie memorial cancer center and institute of oncology iii dept., department of epidemiology and silesia cancer registry, gliwice, poland Purpose or Objective Despite of confirmed prognostic importance of human papilloma virus (HPV) for patients with head and neck cancer (HNC) such data based on Polish population is scarce. The aim of the study was to estimate the ratio of HPV related tumors in patients with HNC and to evaluate the prognostic role of HPV in patients with pharynx or larynx cancer treated with radiotherapy alone (RT) or in combination with chemotherapy (CHRT) in the Cancer Center-Institute in Gliwice, Poland between 2012 and 2014. Material and Methods 322 consecutive patients with HNC (nasopharyngeal cancer (NPC) 25 (7.8%), oropharyngeal cancer (OPC) 125 (38.8%), hypopharyngeal cancer (HPC) 36 (11,2%), laryngeal cancer (LXC) 132 (41%), cancer of unknown primary (FPI) 4 (1,2%)) treated radically with RT (121/38%) or CHRT (201/62%) have been included. HPV etiology has been confirmed basing on tissue material and/or circulating-free DNA HPV. The ratio of HPV-related tumor has been estimated in all group and in OPC patients. Patients with OPC HPV-related (HPV+) and HPV-not related (HPV-) were compared acc. to other prognostic factors. Three-years local (LC), nodal (NC) control survival rates and disease-free (DFS), distant metastases-free (DMFS) and overall survival (OS) rates were compared for patients with OPC (HPV+) and OPC (HPV-). Results Median follow up was 36 months. HPV-related tumors have been confirmed in 72 (23%) patients, in 3 (4.2%), 58 (80,5%), 1 (1,4%), 9 (12,5%), 1 (1,4%) of patients with NPC, OPC, HPC, LXC and FPI respectively. In OPC patients these with HPV+ and HPV- did not differ by sex and the age. OPC (HPV-) were smokers more often (p=0,0007). T stage in both groups was similar, but N stage was significantly higher in (HPV+) (p=0.03). Patients with OPC (HPV+) had significantly higher 3-year LC (91% v 72%, p=0,006), NC (90% v 70%, p=0,008), DFS (85% v 63%, p=0,008) and OS (78% vs 66%, p=0,17). 3-year DMFS was the same in both groups (93% v 94%, p=0.6). In multivariate analysis HPV appeared to be an independent factor influencing OS ratio. Conclusion HPV-related tumors in Polish patients with HNC could be found in a similar percentage like in other countries, reaching almost half of patients with OPC. Polish patients with OPC (HPV+) are not so young but do not smoke and present higher advanced nodal stage. Our findings confirm that HPV is a strong, independent and beneficial prognostic factor in Polish patients with OPC. EP-1084 Laryngeal preservation using chemo- radiotherapy, single institution experience from Egypt. A. Al Nagmy 1 , T. Shouman 1 , A. Hassouna 1 , M. Gaber 2 1 Cairo University- National Cancer Institute, Radiation Oncology Department, Cairo, Egypt 2 Cairo University- Faculty of medicine, Clinical Oncology Department, Cairo, Egypt Purpose or Objective to evaluate organ preservation by radical radiotherapy ± chemotherapy (CT) in locally advanced laryngeal cancer Material and Methods

To review the outcomes of early-stage oropharyngeal squamous cell carcinoma (OSCC) submitted to primary surgery or primary radiotherapy (RT). Material and Methods Retrospective study of patients diagnosed with OSCC between January 2009 and December 2014, clinically staged cT1 to cT2 cN0/cN1, who underwent primary surgery or primary RT. Cases surgically upstaged were excluded. We analyzed patient charts, imaging and clinical data regarding primary therapy, adjuvant treatment and side effects. Toxicity was graded according to Common Terminology Criteria for Adverse Events (v4.0). Overall survival (OS) and progression-free survival (PFS) were analyzed using the Kaplan-Meier method and log-rank test for group comparison. Time-to-event endpoints were calculated from the date of first treatment. Results We found 61 patients with cT1 to cT2 cN0/cN1 OSCC treated with primary surgery or primary RT. Ten were excluded after surgical upstage. From the remaining 51, 45 were male, with a median age of 56 years. The majority was treated with surgical resection (n=35), followed by RT (n=30) with or without (n=21) chemotherapy (high-dose cisplatin), due to positive (n=9), close (<5mm, n=20) or non-evaluable (n=3) margins. Sixteen were submitted to primary RT, with or without (n=13) concomitant chemotherapy. Disease was in stage I in 10 patients, stage II in 24 and stage III in 17. Patients were treated with IMRT using simultaneous integrated boost (n=33) or 3D-CRT. Prescribed dose was 60-70Gy to the high-risk PTV and 50- 54Gy to the low/intermediate-risk PTV. Median follow-up time in patients alive was 5 years. Three patients had tumor persistence, 4 had local failure and no one developed distant metastasis. In both groups, median OS and PFS were not reached. In the primary surgery group, 3-year and 5-year OS were 80% and 62%, and 3-year and 5-year PFS were 74% and 50%, respectively. In the primary RT group, both 3-year and 5-year OS were 81%, and 3-year and 5-year PFS were 81% and 70%, respectively. There was no significant difference in the two groups (OS p value = 0,4; PFS p value = 0,3). Acute grade 3 toxicity was reported by 15 patients (mucositis, dysphagia, dermatitis, xerostomia). Late side effects were grade 1 xerostomia (n=10) and mandibular osteoradionecrosis (ORN, n=6). ORN occurred in patients submitted to primary (n=3) or adjuvant RT, who had been given 66-70Gy with 3D-CRT (n=4) or concomitant cisplatin (n=2). Fourteen died due to disease progression (n=3), treatment complications (sepsis, n=1) or other unrelated causes. Conclusion In our study, there was no significant difference in the OS and PFS between primary surgery vs. primary RT. Although surgery was the most frequent primary approach, almost all patients required adjuvant treatment due to close margins. Our toxicity profile reminds us that careful patient selection is necessary as well as further surgical margins studies are warranted to identify subgroups where treatments can be safely avoided. EP-1083 HPV as an etiological and prognostic factor for the Polish patients with HNC. A. Brewczyński 1 , T. Rutkowski 2 , A. Mazurek 3 , M. Snietura 4 , Z. Kołosza 5 , A. Wygoda 2 , K. Składowski 2 , A. Celejewska 1 , E. Małusecka 3 , A. Fiszer-Kierzkowska 3 , U. Bojko 3 , W. Pigłowski 4 , A. Hajduk 2 , P. Polanowski 2 , U. Dworzecka 2 , I. Gawron 2 , M. Kentnowski 2 , B. Pilecki 2 , T. Stępień 2 , I. Domińczyk 2 , E. Nadolska 2 , A. Tatar 2 , P. Widłak 3 1 Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology III Dept., Department of Radiotherapy, Gliwice, Poland 2 Maria Sklodowska-Curie Memorial Cancer Center and Institute of oncology iii dept., i radiation and clinical oncology department, gliwice, polan