ESTRO 37 Abstract book

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ESTRO 37

patients had a Gleason score of 7, all other patients (17 (41.5%)) were Gleason score 6. Low grade acute genito-urinary symptoms were prevalent among 53.7% of patients (22/41) at baseline. At six months 47.5% (95% CI 31.5-63.9%) of patients experienced GU symptoms, and this declined to 22.5% (10.8-38.4) by 12 months. At six and 12 months 3 and 2 patients respectively experienced grade 2 symptoms. Five percent (2/41) of patients reported acute gastrointestinal symptoms at baseline. At 6 months 22.5% (10.8-38.4%) of patients reported GI symptoms, 1 patient grade 2. At 12 months the same proportion 22.5% (10.8- 38.4%) reported GI symptoms, 2 patients with grade 2. No patients experienced grade 3 GI toxicity. At baseline the median PSA was 10.5 (IQR 8.0-13.3) and ranged from a minimum of 4.3 to 29.9 ng/ml. At 6 months median PSA was 0.5 (IQR 0.2-1.1) and ranged from a minimum of 0.1 to 3.9 ng/ml. At 12 months the median was 0.5 (0.2-0.8) and ranged from 0.1 to 3.6 ng/ml. Conclusion SABR for this group of patients was delivered safely using Rapidarc® FFF for treatment and online CBCT for set-up correction. Few patients presented with grade 2 GU/GI symptoms and none with grade 3 at 6 or 12 months. Longer follow-up is required to further assess PSA response and freedom from biochemical failure. OC-0097 Awareness and surveillance reduces head and neck radiotherapy treatment length J. Gornitzka 1 , P. Andersen 1 , M. Nielsen 2 , A. Bertelsen 2 , L. Johnsen 2 , J. Johansen 1,3 , C. Rønn Hansen 2,3 1 Odense University Hospital, Department of Oncology, Odense, Denmark 2 Odense University Hospital, Laboratory of Radiation Physics, Odense, Denmark 3 University of Southern Denmark, Institute of Clinical Research, Odense, Denmark Purpose or Objective Treatment course length is of essential importance in radiotherapy of head and neck cancer patients. National guidelines prescribe a maximum course length of 41 days for moderate accelerated treatments (6 fractions/week), and 48 days for non-accelerated treatments (5 fractions/week). The purpose of this study is to measure the time from the first to last fraction in a cohort of head and neck cancer patients treated 2003-2017, and to evaluate the effect of increased awareness of the importance of treatment course length. Material and Methods The study included 2,011 head and neck cancer patients treated between 2003 to 2017 to 66-68 Gy in 33-34 fractions and never re-irradiated. As a part of a National Cancer Plan in 2005 the focus increased on the “Patient pathways in packages”. From 2011 the department scheduled QA and service on treatment machines outside clinical hours to reduce non-treatment days. In February 2016, a systematic weekly review of the planned treatment course was introduced, where total radiation treatment course length was checked, and it was ensured that the first treatment was not on a Friday and the last treatment not on a Monday. Patients with scheduled treatment violations, according to national guidelines, are conferred with the responsible oncologist and the treatment plan is compensated with an extra fraction in the last week of treatment. Results The mean length of accelerated treatment courses was reduced from 40.9 days in 2007 to 38.3 days in 2017. For non-accelerated courses, the mean was reduced from 50.3 days in 2007 to 45.9 days in 2017 (fig. 1), making the treatment approximately 2 Gy more effective due to the reduced repopulation of the tumour.

Rescheduled QA and service reduced the fraction of treatment course time violations according to guidelines to less than 20 % for accelerated treatments and to less than 40 % for the non-accelerated treatments after 2011 (fig. 2). The introduction of the systematic review of treatment schedule reduced the fractions of treatment course time violations to 4 % for accelerated treatments, and to 13 % for the non-accelerated treatments (fig. 2). The surveillance alternates between two radiation therapists and takes approximately 5-15 minutes per week.

Conclusion Awareness and continual review of treatment schedules of head and neck cancer patients reduced the treatment course duration.

Poster Viewing : Poster viewing 2: Upper GI

PV-0098 Preoperative Nomogram for Early recurrence after Trimodality Therapy in Esophageal Adenocarcinoma. L. Goense 1 , P.S.N. Van Rossum 1 , M. Xi 2 , D.P. Maru 3 , B.W. Carter 4 , G.J. Meijer 1 , L. Ho 5 , R. Van Hillegersberg 6 , W.L. Hofstetter 7 , S.H. Lin 8 1 UMC Utrecht, Department of Radiation Oncology, Utrecht, The Netherlands 2 Collaborative Innovation Centre for Cancer Medicine, Department of Radiation Oncology, Guangzhou, China 3 The University of Texas MD Anderson Cancer Center, Department of Pathology, Houston, USA 4 The University of Texas MD Anderson Cancer Center, Department of Diagnostic Radiology, Houston, USA 5 The University of Texas MD Anderson Cancer Center, Department of Gastrointestinal Medical Oncology, Houston, USA