Abstract Book

S706

ESTRO 37

comparisons for mean right lung V 17 Gy techniques are summarised in Table 1. WT(FB) Standard match- plane WT(FB) Superior match- plane

for the three

RIBP 21 ±10y; RT-VRI 28 ±9y. Lifelong antiplatelet therapy was prescribed. Phlebography/ arteriography undergone, were followed for 6 pts/11 by a percutaneous transluminal angioplasty (PTA) arterial (n=4) and/or venous (n=4), especially if 3 segments lymphedema. Conclusion The frequency of radiation-induced vasculopathy (VRI) is underestimated while 60% of patients in our RIBP trial presented with an arterial and/or venous stenosis in the next decade (threatening for a third). A vascular assessment by angio-CT during RIBP follow-up seems useful, because of accessibility to a medical and endoluminal treatment. Ref: Delanian: RI neuropathy in cancer survivors. Radiother Oncol 2012; 105: 273 EP-1285 Immediate breast reconstruction followed by adjuvant radiotherapy. Aesthetics and Quality of life. A.A. Diaz Gavela 1 , E. Del Cerro 1 , F. Marcos 1 , F. Counago 1 , Y. Molina 2 , I. Sanz 3 , A. Henríquez 4 , J. Hornedo 5 1 Hospital Quiron Madrid, Radiation Oncology, Pozuelo de Alarcon- Madrid, Spain 2 Hospital Quiron Madrid, Radiophysics, Pozuelo de Alarcon- Madrid, Spain 3 Hospital Quiron Madrid, Plastic and aesthetic surgery department, Pozuelo de Alarcon- Madrid, Spain 4 Hospital Quiron Madrid, Gynecology Service, Pozuelo de Alarcon- Madrid, Spain 5 Hospital Quiron Madrid, Medical Oncology, Pozuelo de Alarcon- Madrid, Spain Purpose or Objective A delayed reconstruction with autologous tissue is preferred if there is an indication of administering post- mastectomy adjuvant radiotherapy (PMRT), but in some cases this is not possible. Sometimes the indication arises after surgery; in other cases there is an explicit request of the patient for an immediate reconstruction. We’ll show our results irradiating patients that have being reconstructed with a tissue expander, focusing in the side effects and the opinion of the patients about this reconstructive approach. Material and Methods We included 47 patients with a mean age of 46 years, treated from Jan 2010 to Dec 2015. The PTV received 50Gy/25fr and PMRT always started after the last expansion. We evaluated acute and chronic side effects as well as the dosimetric disturbances caused by the metallic membrane of the expander. The replacement of the expander by a definitive prosthesis was performed on average 8 months after the PMRT. 27 of these patients also agreed to answer a questionnaire about their global and aesthetic level of satisfaction, which was performed at least six months after the replacement surgery. In addition, the resulting aesthetics was evaluated independently by two physicians of the Department of Radiation Oncology according to the scales of Harris Van Limbergen and Baker’s. Results There were no unexpected PMRT acute side effects, being the grade 1-2 radiodermatitis and the fatigue the most frequent. Between the end of the PMRT and the replacement of the expander, none of the patients suffered from infection, dehiscence or necrosis. Chronic pain was uncommon and no patient required higher analgesia than step 1 of the WHO analgesic ladder. Punctuation of the long term aesthetic evaluation between both clinicians was no statistically different. 77% of the patients had grade 1-2 toxicity with visible or palpable changes in the appearance of the breast. All patients had some degree of fibrosis but only seven suffered from grade 3 fibrosis/ capsular contracture. One patient needed further surgery to correct an implant displacement.

WT(DIBH) Standard match- plane

Mean Right Lung V 17 Gy (%)

37.3

30.4

29.4

95%

Confidence

33.9-40.6 28.1-33.4 26.5-32.3

interval (%) Proportion

of

patients meeting the ipsilateral lung V 17 Gy constraint (≤35%)

5/14

12/14

13/14

There was a statistically significant difference between WT(FB) standard match-plane and WT(FB) superior match-plane (p<0.0001). There was also a statistically significant difference between WT(FB) standard match- plane and WT(DIBH) standard match-plane (p=0.0003). There was no significant difference between WT(FB) superior match-plane and WT(DIBH) standard match- plane (p=0.6720). Conclusion DIBH is the most reliable technique for meeting the lung constraint in right-breast-affected patients undergoing IMC-RT but cranial displacement of the match-plane offers a viable alternative where DIBH is not available. EP-1284 Axillo-Subclavian Vascular Entrapment In Radiation Plexitis Revealed Throughout A Randomized Trial S. Delanian 1 , I. Klein 2 , J. Massoni 3 , M. Dadon 3 , S. Awad 4 , S. Vignes 5 , P. Pradat 6 1 Hôpital Saint-Louis- APHP, Oncologie-Radiothérapie, Paris, France 2 Clinique Labrouste, Neuro-Radiolologie, Paris, France 3 Centre d'explorations, vasculaires, Paris, France 4 Clinique Labrouste, Radiologie Interventionnelle, Paris, France 5 Hôpital Cognacq-Jay, Lymphologie, Paris, France 6 Hôpital Pitié-Salpêtrière- APHP, Neurologie, Paris, France Purpose or Objective Radiation-induced brachial plexopathy (RIBP) is a chronic progressive injury of the peripheral nerve after radiotherapy, characterized by direct axonal degeneration- demyelination and indirect fibrosis with capillary network failure. However, literature is poor on the related neighboring large vessels injuries. In a therapeutic phase III trial (NCT01291433), for long adults survivors suffering from RIBP after breast cancer, a vascular exploration was realized whenever suggestive 32 RIBP of the randomized PENTOCLO trial on 47 (age 67y, 20y after cancer, lymphedema in half), were explored for vascular signs: acrocyanosis, cold hand, weak radial pulse, increased pain, venous collateral circulation, worsened arm lymphedema volume. Between 2015/03 -2017/03, monocentric angio-CT/ MR- angiography and arterio-venous duplex ultrasound of axillary-subclavian vessels were realized by experimented practitioners. More invasive exploration was offered secondly in severe cases. Results Twenty eight patients/ 32 (88%) presented with an arterial and/or venous axillo-subclavian long (6-8 cm) ± short stenosis: 11 tights -occlusion and 17 moderated (30- 60%). The main area was the inter-scalenic triangle (subclavian neuro-vascular interchange), then the axillar volume. Mean delays were RT-lymphedema 8 ±8y; RT- clinical signs existed. Material and Methods