ESTRO 37 Abstract book

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ESTRO 37

Conclusion The ESTRO defined margin of 5mm covers IMN nodes in only 72% of the treatment naïve patients and a larger 7mm margin might be required to cover the target in the same patients. No nodes were found posterior to the vessel and the margin can be safely shaved till the lung/wall interface posteriorly. EP-1349 Acute skin toxicity of hypofractionated whole breast radiotherapy in large-breasted patients V. Carrizo Ibarra 1 , V. García Reglero 1 , J.E. Baquedano 1 , E. García Alonso 1 , M. Mira Flores 1 , B. Domingo 2 , O. Torne 2 , P. Vicente 2 , J.A. Carceller Vidal 1 1 Hospital Universitario Arnau de Vilanova- Lleida, Radiation oncology department, Lleida, Spain 2 Hospital Universitario Arnau de Vilanova- Lleida, Radiation oncology- nursery department, Lleida, Spain Purpose or Objective The objective of this study is to evaluate skin toxicity in obese and large- breasted women with an early breast cancer treated with hypofractionated schedule (dose 40.05 Gy to 2.67 Gy per session) after breast conserving surgery. Material and Methods From 2012 to 2015, a total of 350 breast cancer patients were treated with 3-dimensional conformal radiotherapy with a hypofractionated schedule. The patients received 40,05 Gy in 15 daily fractions. Acute skin toxicity was monitored during and after radiotherapy according to RTOG scale. Results Out of the 350 patients were treated in our centre, 34.85% of the patients (122) had a breast volume (PTV) of > 1000 cc. and 12% (42) had PTV > 1500 cc. In the subgroup of patients with PTV within 1000 cc and 1500 cc, 70.9 % presented acute toxicity grade 1 and 27.8% presented acute toxicity grade 2. In these patients, grade 2 toxicity was localized in 38% in the submammary region and 62% in the axillary region. In the subgroup of patients with a PTV > 1500 cc, 32,6% presented acute toxicity grade 1 and 67,9% presented acute toxicity grade 2. In these patients, grade 2 toxicity was localized in 80% in the submammary region and 20% in the axillary region. No grade 3 toxicity was reported in any of the subgroups. Skin toxicity was treated with moisturizing cream, corticosteroid ointments or healing cream if needed with good cosmetic results after 15 days of finishing the radiation treatment.

Conclusion Hypofractionated breast radiation is a well-tolerated treatment even in patients with large breasts. Patients with PTV volume> 1500 should be extremely careful in the submammary region. The size of the breast should not be an impediment to receive hypofractionated radiotherapy treatments. EP-1350 Capacity of resilience during radiotherapy treatment in breast cancer D.M. Muñoz Carmona 1 , R. De Haro Piedra 1 , J. Nieto- Guerrero 1 , J. Flores Rodríguez 1 , B. López Díez 2 , M. Ortíz Gordillo 1 1 University Hospital Virgen del Rocío, Radiation Oncology, Seville, Spain 2 Psicooncology Ministry of Defense Military Corps of Health, Psicooncology, Seville, Spain Purpose or Objective We intend to analyze whether women during radiotherapy treatment score high in resilience and whether or not they are strengthened from the breast cancer process. Material and Methods An observational, descriptive, prospective study to whom we conducted the Wagnild and Young Resilience Survey. Results We analyzed 140 patients. Mean 61y.(47-86). 81% received hypofractionated schedule (40.05Gy/ 2.67Gy/15sessions); 20% standard schedule (50Gy/2Gy/ 25sessions). Postmenopausal 64%; Premenopausal 36%. Bilateral tumor 3.6%; Right breast 46.4%, left breast 50%. Conservative surgery 61%; lumpectomy 21%; Mastectomy 18%. Stage 0: 2%; Stage I: 46,8%; Stage II: 34.4%; Stage III: 17%. The average resilience score was 141.91 (138-145). Analyzing aCronbach reliability of 0.927 (high reliability). Resilience is not affected by the hormonal state p=0.152; The mastectomized patients did not score worse than the rest of those receiving conservative surgery p=0.116; There were no significant differences in hypofractionated and standard treatment (p=0.244), but patients with a hypofractionated had an average resilience score higher than those receiving the standard treatment. Concomitant treatment with radiotherapy, there is also no significant relationship p=0.140, but those that do not carry any concomitant treatment score higher in resilience. Patients taking anxiolytics or antidepressant, score lower than those who do not take P<0.001 and P<0.05.