AUTHOR=Hong Ji Hyun , Song Jin-Ho , Choi Kyu-Hye , Kim Shin Woo , Park Woo-Chan , Lee Jieun , Lee Ahwon , Kang Jun , Choi Byung-Ock TITLE=De-escalation of regional nodal irradiation fields in pT1-2N1 breast cancer patients after breast conserving surgery: retrospective real-world clinical experience JOURNAL=Frontiers in Oncology VOLUME=15 YEAR=2025 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2025.1484190 DOI=10.3389/fonc.2025.1484190 ISSN=2234-943X