Post-Mastectomy Radiotherapy After Neoadjuvant Chemotherapy in Breast Cancer: A Pooled Retrospective Analysis of Three Prospective Randomized Trials

Journal Article · Fri Nov 15 04:00:00 EST 2019 · Annals of Surgical Oncology (Online)

DOI:https://doi.org/10.1245/S10434-019-07635-X· OSTI ID:22927539

Krug, David ^[1]; Lederer, Bianca; Seither, Fenja; Nekljudova, Valentina ^[2]; Ataseven, Beyhan ^[3]; Blohmer, Jens-Uwe ^[4]; Denkert, Carsten ^[5]; Ditsch, Nina ^[6]; Gerber, Bernd ^[7]; Hanusch, Claus ^[8]; Heil, Joerg ^[9]; Hilfrich, Jörn ^[10]; others, and

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1. University Hospital Schleswig-Holstein, Department of Radiation Oncology (Germany)
2. German Breast Group (Germany)
3. Kliniken Essen-Mitte, Department of Gynecology and Gynecologic Oncology (Germany)
4. Charité, Klinik für Gynäkologie (Germany)
5. Philipps-University Marburg, Institute for Pathology (Germany)
6. Ludwig-Maximilians-University of Munich, Department of Obstetrics and Gynecology (Germany)
7. University Hospital, Department of Gynecology and Obstetrics (Germany)
8. Rotkreuzklinikum München, Frauenklinik (Germany)
9. University of Heidelberg, Breast Unit, University Hospital (Germany)
10. Frauenklinik Henriettenstiftung (Germany)

Background: The impact of locoregional radiotherapy (RT) after neoadjuvant chemotherapy (NACT) and mastectomy in breast cancer patients is currently unclear. Several publications have suggested that patients with a favorable response to NACT might not benefit from RT after mastectomy. Methods: A retrospective analysis of three prospective randomized NACT trials was performed. Information on the use of RT was available for 817 breast cancer patients with non-inflammatory breast cancer who underwent mastectomy after NACT within the GeparTrio, GeparQuattro, and GeparQuinto-trials. RT was administered to 676 of these patients (82.7%). Results: The 5-year cumulative incidence of locoregional recurrence (LRR) was 15.2% (95% confidence interval [CI] 9.0–22.8%) in patients treated without RT and 11.3% in patients treated with RT (95% CI 8.7–14.3%). In the multivariate analysis, RT was associated with a lower risk of LRR (hazard ratio 0.51, 95% CI 0.27–1.0; p = 0.05). This effect was shown especially in patients with cT3/4 tumors, as well as in patients who were cN+ before neoadjuvant therapy, including those who converted to ypN0 after neoadjuvant therapy. In the bivariate analysis, disease-free survival was significantly worse in patients who received RT, however this was not confirmed in the multivariate analysis. Conclusions: Our results suggest that RT reduces the LRR rates in breast cancer patients who receive a mastectomy after NACT without an improvement in DFS. Prospective randomized controlled trials such as the National Surgical Adjuvant Breast and Bowel Project B-51/RTOG 1304 trial will analyze whether RT has any benefit in patients who have a favorable response after NACT.

• OSTI ID: 22927539
• Journal Information: Annals of Surgical Oncology (Online), Journal Name: Annals of Surgical Oncology (Online) Journal Issue: 12 Vol. 26; ISSN 1534-4681
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CHEMOTHERAPY
MAMMARY GLANDS
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PATIENTS
RADIOTHERAPY
SURGERY