ESTRO 36 Abstract Book

S975 ESTRO 36 2017 _______________________________________________________________________________________________

cavity, 250µm in diameter and 4mm deep, is filled with the scintillating material, terbium doped gadolinium oxysulphide (Gd 2 O 2 S:Tb, GOS) and sealed with epoxy. The scintillation material fluoresces on exposure to ionising radiation and the resultant emitted fluorescent light penetrates the PMMA optical fibre core and propagates along the fibre to a Hamamatsu Multi-Pixel Photon Counting Module (MPPC C11208) for monitoring of the optical signal.

postmenopausal women. The main anatomical location is the vulva (65%), followed by the perianal region, scrotum, penis and axilla. The disease presents with well-defined eczematous eruption or leukokeratotic plaque, and a tendency for multifocal lesions. The standard treatment for local EMPD is surgical resection, although this approach might not be suitable for all patients. Topical treatments such as Imiquimod cream, 5-fluorouracil cream and CO2 laser may also be used, with variable results. Recently, radiotherapy (RT) has been widely used to treat EMPD. RT can be used as the primary treatment in elderly patients with comorbidities who are considered medically inoperable, or in patients who want to preserve body function or structure. In a review of the literature, we found only three patients of Paget extramammary treated with HDR-plesiotherapy by custom mold. Material and Methods We present a case of Paget’s disease treated by HDR- plesiotherapy with a custom made mold with curative intention. A 80-year-old female presented with a 2-year history of a skin lesion in the glutes, intergluteal folds and vulva, about 11-12 cm, whith pruritus, erythema, and punctate bleeding. Positive biopsy for EMPD. Additional exams did not reveal an underlying malignancy. The patient was treated initially by means of topical applications of imiquimod cream but in the absence of response she was referred to the Radiation Oncology Department. Treated by HDR-plesiotherapy with a custom-made mold with up to a final dose 50 Gy in 10 fractions of 500 cGy, two days a week (EQD2 62.5Gy). Results Acute adverse effects include epithelitis grade 2 and epithelitis small areas grade 3, which resolve with topical measures. After three months of treatment, the patient had complete response and resolution epithelitis. Conclusion In our opinion, HDR plesiotherapy with a custom-made mold appears to be an ideal alternative for elderly patients with comorbilities, not candidates for aggressive surgical management or who refuse surgery. EP-1802 The role of the high dose rate brachytherapy in the conservative treatment of esophageal cancer. A. Lozhkov 1 , A.V. Vazhenin 1 , T.M. Sharabura 1 1 Chelyabinsk Regional Oncol.Centre, Department for Radiotherapy and Radio-Oncology, Chelyabinsk, Russian Federation Purpose or Objective To evaluate the results of add to EBRT intraluminal HDR brachytherapy. Material and Methods Between 2008 and 2015, 82 people with cancer of the thoracic esophagus T2-3N0-1M0 and refusal of surgery received radiation therapy. In the first phase all patients underwent external beam radiotherapy up to 40-50 Gy. Subsequently, the patients were divided into 3 groups. The first group included 30 patients who received concomitant radiotherapy using brachytherapy, in the 2nd group -30 patients who received EBRT 60-70 Gy, in 3 group -22 patients received EBRT 40-

Results The sensor was further evaluated for its response to different levels of radiation to determine its suitability for brachytherapy applications. The sensor is exposed to a full cartridge, i.e. 15 seeds, corresponding to an activity of 5.35mCi and to a second full cartridge corresponding to an activity of 4.45mCi. Alongside the optical fibre sensor, the charge was also collected within a Standard Imaging HDR 1000 Well Chamber and a reading displayed on the Standard Imaging Max 4000 Electrometer. Fig 2 shows the average photon counts equate to 750 for 5.35mCi and 655 for 4.45mCi, corresponding to a 12.6% reduction in photon counts. The radiation activity of 5.35mCi resulted in a current of 18.47pA and 4.45mCi directly equating to a 13.6% reduction in activity.

Conclusion The sensor demonstrates excellent stability, with a standard deviation of 18 counts. The current repeatability, with a maximum percentage deviation of 3.3%, is within accepted limits, however it is envisaged that the future experimental set-up employing a brachytherapy phantom, will significantly improve this.

Electronic Poster: Brachytherapy: Miscellaneous

EP-1801 HDR-plesiotherapy for the treatment of extramammary paget’s disease. A case report. M.F. Ropero Carmona 1 , J. Lupiani Castellanos 1 , J. Quirós Rivero 1 , A. Ruiz Herrero 1 , M.A. Gonzalez Ruiz 1 , J. Cabrera Rodriguez 1 , Y. Ríos Kavadoy 1 , J.L. Muñoz Garcia 1 , P. Almendral Manzano 1 1 Hospital Universitario Infanta Cristina, Radiotherapy Oncologist, Badajoz, Spain Purpose or Objective In 1889, Crocker first described extramammary Paget’s disease (EMPD). It is considered a rare adenocarcinoma that originates from the skin or skin appendages in areas with apocrine glands. EMPD classification is based on the presence or absence of associated malignancies: Primary or intraepithelial and Secondary. It is more common