ESTRO 2024 - Abstract Book

S490

Clinical - Breast

ESTRO 2024

as cases where the plastic surgery department performed either breast capsulectomy (N751) or surgical debridement (SC021-027) after radiotherapy. Propensity score matching method was adopted to constitute the matched cohort between the hypofractionated fractionation (HF) and the conventional fractionation (CF), adjusted for age, diabetes, hypertension, PMRT technique, use of bolus, year of PMRT delivery, and reconstruction method.

Results:

Altogether 4,669 patients were analyzed: 1,430 (30.6%) in the HF group and 3,239 (69.4.%) in the CF group. The use of HF has steadily increased from 19.4% in 2015 to 41.0% in 2020. Delayed 2-stage implant reconstruction method (33.9%) was the most frequently used, followed by immediate autologous (32.9%) and immediate implant (22.5%). In the matched cohort for immediate reconstruction (N=1,286), the complication rate was not significantly different between the HF group and the CF group (5.1% [33/643] vs. 5.4% [35/643], P=0.803) with the median follow-up of 2.5 Similarly, the complication rate for delayed 2-stage reconstruction (N=784), was not significantly different between the HF group and the CF group (10.4% [41/392] vs. 10.7% [42/392], P=0.856) with the median follow-up of 2.6 years

Conclusion:

In a nationwide insurance cohort, the complication rate was not significantly different between the HF group and the CF group. Our data suggest HF for reconstructed breasts is comparable to CF. However, consultation for fractionation regimen for reconstructed breast cancer patients may be still required at time of consideration of PMRT.

Keywords: Postmastectomy radiotherpy, Breast reconstruction

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Digital Poster

Risk factor analysis of post-irradiation capsular contracture following implant-based reconstruction

Maria Vinsensia 1 , Riccarda Schaub 1 , Eva Meixner 1 , Philipp Hoegen 1 , Nathalie Arians 1 , Tobias Forster 1 , Line Hoeltgen 1 , Clara Köhler 1 , Kristin Lang 1 , Vania Batista 1 , Laila König 1 , Oliver Zivanovic 2,3 , Andre Hennigs 2,3 , Michael Golatta 2,3 , Jörg Heil 1,3 , Jürgen Debus 1,4 , Juliane Hörner-Rieber 1,5 1 Heidelberg University Hospital, Department of Radiation Oncology, Heidelberg, Germany. 2 Heidelberg University Hospital, Department of Gynecology and Obstetrics, Heidelberg, Germany. 3 Klinik St. Elisabeth, Brustzentrum Heidelberg, Heidelberg, Germany. 4 German Cancer Research Center (DKFZ), Clinical Cooperation Unit Radiation Oncology, Heidelberg, Germany. 5 German Cancer Consortium (DKTK), Partner Site Heidelberg, Heidelberg, Germany

Purpose/Objective: