%0 Journal Article %A Haussmann, Jan %A Budach, Wilfried %A Corradini, Stefanie %A Krug, David %A Bölke, Edwin %A Tamaskovics, Balint %A Jazmati, Danny %A Haussmann, Alexander %A Matuschek, Christiane %T Whole Breast Irradiation in Comparison to Endocrine Therapy in Early Stage Breast Cancer-A Direct and Network Meta-Analysis of Published Randomized Trials. %J Cancers %V 15 %N 17 %@ 2072-6694 %C Basel %I MDPI %M DKFZ-2023-01888 %P 4343 %D 2023 %X Multiple randomized trials have established adjuvant endocrine therapy (ET) and whole breast irradiation (WBI) as the standard approach after breast-conserving surgery (BCS) in early-stage breast cancer. The omission of WBI has been studied in multiple trials and resulted in reduced local control with maintained survival rates and has therefore been adapted as a treatment option in selected patients in several guidelines. Omitting ET instead of WBI might also be a valuable option as both treatments have distinctly different side effect profiles. However, the clinical outcomes of BCS + ET vs. BCS + WBI have not been formally analyzed.We performed a systematic literature review searching for randomized trials comparing BCS + ET vs. BCS + WBI in low-risk breast cancer patients with publication dates after 2000. We excluded trials using any form of chemotherapy, regional nodal radiation and mastectomy. The meta-analysis was performed using a two-step process. First, we extracted all available published event rates and the effect sizes for overall and breast-cancer-specific survival (OS, BCSS), local (LR) and regional recurrence, disease-free survival, distant metastases-free interval, contralateral breast cancer, second cancer other than breast cancer and mastectomy-free interval as investigated endpoints and compared them in a network meta-analysis. Second, the published individual patient data from the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) publications were used to allow a comparison of OS and BCSS.We identified three studies, including a direct comparison of BCS + ET vs. BCS + WBI (n = 1059) and nine studies randomizing overall 7207 patients additionally to BCS only and BCS + WBI + ET resulting in a four-arm comparison. In the network analysis, LR was significantly lower in the BCS + WBI group in comparison with the BCS + ET group (HR = 0.62; CI-95 %K Network meta-analysis (Other) %K breast cancer (Other) %K de-escalation (Other) %K endocrine therapy (Other) %K radiotherapy (Other) %F PUB:(DE-HGF)16 %9 Journal Article %$ pmid:37686620 %2 pmc:PMC10487067 %R 10.3390/cancers15174343 %U https://inrepo02.dkfz.de/record/282895