ESTRO 36 Abstract Book

S727 ESTRO 36 2017 _______________________________________________________________________________________________

mean PTV Boost

(SD, range) HI was 0.08 (0.02; 0.05-0.11)

Each patient had endoscopic biopsy confirming primary oesophageal melanoma. Prior to treatment whole-body PET scans were performed to aid tumour localisation and exclude nodal or distant metastases. PET scans were repeated after completion of radiotherapy and patients were followed-up clinically thereafter. Each patient gave written consent for publication. Two patients (A&B) received 50 Gy in 16 daily fractions using a 3D conformal technique. The third patient (C) received 30 Gy in 10 daily fractions followed by intraluminal brachytherapy (16 Gy in 2 treatments, one week apart). Results In all three cases tumours were Braf wildtype, PET-avid on pre-treatment scans and no distant or nodal metastases were identified. All three patients developed odynophagia requiring analgesia during and for several weeks following treatment and lost weight, though no patient required admission or enteral feeding support. On post-treatment PET scans all patients had a response in the oesophageal primary; Patient A had a complete response. She remained disease- free, with normal swallowing, until she died due to myocardial infarction, 30 months after diagnosis (26 months since completion of treatment). B had a good partial response; pretreatment 6 cm tumour with SUVmax 20.8 - following treatment 2.8 cm,SUVmax 9.7. His swallowing remained normal without further intervention until 24 months after diagnosis (22 months after treatment) - at which point he reported mild dysphagia and a further endoscopy identified residual melanoma. He remains stent-free. C had complete response of the primary oesophageal melanoma but the post-treatment PET identified metastatic disease in both lungs and peritoneal cavity. She died 12 months after diagnosis (9 months after treatment).

and 0.07 (0.03; 0.05-0.12) (p=0.31) respectively.

No statistically significant difference in target volume coverage or dose to rectum, other bowel or bladder outside PTV Boost was seen between the two plans. Table below summaries the dosimteric outcomes. Conclusion SIB delivery was achieved with comparable target and normal tissue constraints for both techniques. VMAT faster delivery times are likely to mean it is favoured for this group of patients both because of reduction in intra- fraction organ filling opportunity and departmental 1. Huddart RA, Hall E, Hussain SA, Jenkins P, Rawlings C, Tremlett J, Crundwell M, Adab FA, Sheehan D, Syndikus I et al : Randomized noninferiority trial of reduced high- dose volume versus standard volume radiation therapy for muscle-invasive bladder cancer: results of the BC2001 trial (CRUK/01/004). Int J Radiat Oncol Biol Phys 2013, 87(2):261-269 2. Cowan RA, McBain CA, Ryder WD, Wylie JP, Logue JP, Turner SL, Van der Voet J, Collins CD, Khoo VS, Read GR: Radiotherapy for muscle-invasive carcinoma of the bladder: results of a randomized trial comparing conventional whole bladder with dose-escalated partial bladder radiotherapy. Int J Radiat Oncol Biol Phys 2004, 59(1):197-207. Acknowledgments We acknowledge NHS funding to the NIHR Biomedical Research Centre for Cancer and to Cancer Research UK (CRUK). throughput. References EP-1371 Primary oesophageal melanoma responds to hypofractionated radiotherapy K. Griffin 1 , A. Scarsbrook 2 , W. Merchant 1 , G. Radhakrishna 3 , O. Donnelly 3 1 St James' Institute of Oncology, Pathology, Leeds, United Kingdom 2 St James' Institute of Oncology, Radiology, Leeds, United Kingdom 3 St James' Institute of Oncology, Oncology, Leeds, United Kingdom Purpose or Objective Oesophageal melanoma is rare; current practice would be to consider surgical treatment first, with radiotherapy reserved for unresectable or patients not suitable for oesophagectomy. We report our experience of three consecutive patients who responded to high-dose hypofractionated radiotherapy to localised oesophageal Electronic Poster: Clinical track: Skin cancer / malignant melanoma

Conclusion Oesophageal primaries are a rare site for non-cutaneous melanomas with little evidence to guide management. Based on our series tumours are FDG-avid and PET-CT is likely to be useful in planning treatment. Hypofractionated radiotherapy appears to be effective in achieving local control and should be considered an alternative to surgery for melanoma arising in the oesophagus. EP-1372 Preliminar results of fractionated cyberknife stereotactic radiotherapy for uveal melanoma. I. Bossi Zanetti 1 , M. Pellegrini 2 , G. Beltramo 1 , V. Ravera 2 , A. Bergantin 1 , A.S. Martinotti 1 , I. Redaelli 1 , P. Bonfanti 1 ,

melanoma primaries. Material and Methods