Hypofractionation with simultaneous integrated boost after breast-conserving surgery: Long term results of two phase-II trials
Charlotte Pfaffendorf,
Reinhard Vonthein,
Katja Krockenberger-Ziegler,
Kathrin Dellas,
Andreas Schreiber,
Dorit Uhlemann,
Stefan Dinges,
Florian Würschmidt,
Peter Andreas,
Evelyn Weinstrauch,
Kirsten Eilf,
Dirk Rades,
Ulrike Höller,
Stephanie E. Combs,
Renata Kazmierczak,
Fabian Fehlauer,
Ulrike Schreck,
Jörg Zimmer,
Jürgen Dunst,
David Krug
Affiliations
Charlotte Pfaffendorf
Klinik für Strahlentherapie, Universitätsklinikum Schleswig-Holstein und Christian-Albrechts-Universität zu Kiel, Germany
Reinhard Vonthein
Institut für Medizinische Biometrie und Statistik, Universität zu Lübeck, Universitätsklinikum Schleswig-Holstein, Germany
Katja Krockenberger-Ziegler
ZKS Lübeck, Universität zu Lübeck, Germany; AMEDOM GmbH, Lübeck, Germany
Kathrin Dellas
Klinik für Strahlentherapie, Universitätsklinikum Schleswig-Holstein und Christian-Albrechts-Universität zu Kiel, Germany
Andreas Schreiber
Praxis für Strahlentherapie, Dresden, Germany
Dorit Uhlemann
Klinik für Strahlentherapie und Radioonkologie, Heinrich-Braun-Klinikum, Zwickau, Germany
Stefan Dinges
Klinik für Strahlentherapie und Radioonkologie, Städtisches Klinikum Lüneburg, Germany
Florian Würschmidt
Radiologische Allianz, Hamburg, Germany
Peter Andreas
Abteilung für Strahlentherapie, Krankenhaus Buchholz, Buchholz in der Nordheide, Germany
Evelyn Weinstrauch
Praxis für Radioonkologie, Johanniter-Zentren für Medizinische Versorgung Stendal, Germany
Kirsten Eilf
Praxis für Strahlentherapie, Kiel, Germany
Dirk Rades
Klinik für Strahlentherapie, Universitätsklinikum Schleswig-Holstein Lübeck, Germany
Ulrike Höller
MVZ Charité Vivantes Strahlentherapie, Germany
Stephanie E. Combs
Klinik für Strahlentherapie, Klinikum Rechts der Isar, TU, München, Germany
Renata Kazmierczak
Visiorad, Pinneberg-Mitte, Germany; Klinik für Strahlentherapie, Universitätsklinikum Hamburg-Eppendorf, Germany
Fabian Fehlauer
Strahlenzentrum Hamburg MVZ, Germany
Ulrike Schreck
Klinik für Radioonkologie und Praxis für Strahlentherapie, ALB FILS Kliniken, Göppingen, Germany
Jörg Zimmer
Praxis für Strahlentherapie, Dresden, Germany
Jürgen Dunst
Klinik für Strahlentherapie, Universitätsklinikum Schleswig-Holstein und Christian-Albrechts-Universität zu Kiel, Germany
David Krug
Klinik für Strahlentherapie, Universitätsklinikum Schleswig-Holstein und Christian-Albrechts-Universität zu Kiel, Germany; Corresponding author. Klinik für Strahlentherapie Universitätsklinikum Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
Purpose: To analyze long-term results of two multicenter prospective single-arm trials (ARO-2010-01 and ARO-2013-04) investigating adjuvant hypofractionated radiotherapy (HF) with simultaneous integrated boost (SIB) after breast-conserving surgery (BCS). Methods: Eligible patients had histopathologically confirmed unifocal breast cancer planned for whole breast irradiation plus boost radiotherapy to the tumor bed. In both studies, a total dose of 40 Gy was applied to the whole breast and of 48 Gy to the tumor bed in 16 fractions of 2.5 and 3.0 Gy. Radiotherapy could be given either as three-dimensional conformal radiotherapy (3D-CRT) or as intensity-modulated radiotherapy (IMRT). The primary study objectives were feasibility and security within an observation period of six months. The current investigation focuses on long-term efficacy and toxicities. Results: Between 2011 and 2014, both trials enrolled 300 patients in total. Data from 274 of these patients could be used for the current analysis. The median follow-up time was 60 months and the 5-year disease-free survival 92.1%. Three patients suffered a local recurrence (after 36–72 months) while a regional recurrence occurred in one patient (after 17 months). The 5-year local control rate in the breast was 99.6%. 63.5% of all patients did not report any late radiation-related toxicity, 28.5% reported grade 1 and 7.3% grade 2 toxicities. The highest late toxicity was grade 3 in 2 women (0.7%, telangiectasia and lymphedema of the breast). Conclusion: Our analysis demonstrates favorable efficacy and low rates of long-term side effects of HF with SIB after BCS. Randomized controlled phase III trials are ongoing.