ESTRO 2023 - Abstract Book

S633

Monday 15 May 2023

ESTRO 2023

Results 126 patients had upper located tumors, and 104 patients had lower located tumors (table 1). 66 (52.4%) of the upper located tumors received RGRT and 60 (47.6%) received free breathing radiation therapy (FBRT). Similarly, for the lower located tumors, 57 (54.8%) received RGRT and 47 (45.2%) received free breath (FBRT). The use of RGRT varied during the period of accrual from 30.3% to 71.1% of the randomised patients and the proportion of patients received RGRT varied from 0 to 95% between the participating centres. The median MHD for all left-sided PBI patients was 0.37 Gy, 0.33 Gy or upper located tumors and 0.46 Gy for lower located tumors. The median MHD for RGRT and FBRT was 0.27 Gy and 0.45 Gy respectively for upper located tumors and 0.40 Gy and 0.54 Gy for lower located tumors (Table 2). In absolute numbers, the use of RGRT resulted in a reduction in median MHD of 0.16 Gy for all patients treated with left- sided PBI, 0.17 Gy for upper located tumors and 0.14 Gy for lower located tumors. Of the evaluated 230 patients, 15 patients (6.5%), three RGRT and twelve FBRT, had a MHD >1.5 Gy. Of these 15 patients, eight had a tumor located in the upper part of the breast, 7 in the lower. Six patients (2.6%) had a MHD >2.5 Gy, two were treated with RGRT, four with FBRT.

Conclusion For patients treated with left-sided PBI there is a significant reduction of MHD by using RGRT independent of tumor location. However, the absolute reduction in MHD is likely of no clinical relevance for the main part of the patients. Patients treated with FBRT were overrepresented in the group of patients with a MHD > 1.5 Gy. Thus, the gain of respiratory gating in PBI may still be clinically relevant in a few selected patients. OC-0767 Effect of manual lymph drainage in people with breast cancer-related lymphedema: EFforT-BCRL trial T. De Vrieze 1,3 , I. Nevelsteen 2 , N. Gebruers 3 , S. Fieuws 4 , S. Thomis 5 , A. De Groef 1 , W. Tjalma 6 , J. Belgrado 7 , L. Vandermeeren 8 , C. Monten 9 , M. Hanssens 10 , N. Devoogdt 1 1 KU Leuven, Rehabilitation Sciences and Physiotherapy, Leuven, Belgium; 2 UZ Leuven, Oncological Surgery, Leuven, Belgium; 3 UAntwerpen, Rehabilitation Sciences and Physiotherapy, Antwerpen, Belgium; 4 KU Leuven, Statistics, Leuven, Belgium; 5 UZ Leuven, Vascular Surgery, Leuven, Belgium; 6 Antwerp University Hospital, Multidisciplinary Breast Clinic, Antwerpen, Belgium; 7 ULB, Lymphology Unit, Brussels, Belgium; 8 Mirha, Lymphedema Clinic, Brussels, Belgium; 9 UZ Gent, Radiology, Gent, Belgium; 10 AZ Groeninge Hospital, Oncology, Kortrijk, Belgium Purpose or Objective Importance: Although worldwide applied for the treatment of breast cancer-related lymphedema (BCRL), the effectiveness of manual lymph drainage (MLD) remains unclear. Since 1930, traditional MLD is applied. Recently, the method of MLD has been optimised by making it patient-tailored (i.e. fluoroscopy-guided MLD). Objective: To investigate the effectiveness of fluoroscopy-guided MLD additional to decongestive lymphatic therapy (DLT), compared to traditional or placebo MLD, for the treatment of BCRL. Materials and Methods Design: Multicentre, three-arm, double-blinded RCT Setting: Five hospitals in Belgium Participants: 194 participants with unilateral chronic BCRL were enrolled. Four patients were lost to follow-up during the intensive treatment phase. Interventions: Participants were randomised into one of three groups, receiving standard DLT (consisting of education, skin care, compression therapy and exercises) either including fluoroscopy-guided MLD (n=63), traditional MLD (n=63) or placebo MLD (n=64). Participants received 14 sessions of physical therapy during the 3-weeks intensive phase and received 17 sessions during the 6-months maintenance phase. Main outcome measures: Primary outcomes were 1) change in excessive volume reduction of the arm/hand, and 2) change in excessive volume accumulation at the shoulder/trunk. Primary endpoint was at the end of the intensive phase.