{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T15:11:54Z","timestamp":1792595514351,"version":"4.5.0"},"reference-count":36,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T00:00:00Z","timestamp":1758499200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T00:00:00Z","timestamp":1758499200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100012834","name":"Gifu University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100012834","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Breast Cancer"],"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Radiofrequency ablation (RFA) is a minimally invasive technique employed in the management of small breast tumors. RFA involves the delivery of a high-frequency current through a needle electrode under ultrasound guidance. In Japan, RFA has been covered by insurance since 2023 as a localized treatment option for early-stage breast cancers.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively analyzed the data of patients who underwent RFA at our institution between February 2016 and March 2025. Breast density was classified into four categories based on the Breast Imaging Reporting and Data System. Associations between breast density and RFA parameters, including ablation temperature, time, and impedance, were evaluated.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 50 breasts in 49 female patients were treated with RFA. The mean peak ablation temperature recorded after the cooling break was 81.0\u2009\u00b1\u20098.0\u00a0\u00b0C. Increased breast density was significantly associated with high temperatures. The mean ablation time until break was 446\u2009\u00b1\u2009139\u00a0s, indicating a trend toward prolonged durations in cases involving denser breast tissue. The mean initial and final impedance values were 208\u2009\u00b1\u200972.3\u202f\u03a9 and 161\u2009\u00b1\u200966.5\u202f\u03a9, respectively. Fat-rich breasts exhibited significantly higher impedance values at both time points.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Fatty breast tissue is associated with higher impedance, lower peak temperatures, and shorter ablation times, potentially resulting in insufficient ablation. Breast density should be considered when planning RFA to ensure optimal treatment efficacy.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s12282-025-01775-7","type":"journal-article","created":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T06:05:02Z","timestamp":1758521102000},"page":"72-79","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Impact of breast density on the efficacy of radiofrequency ablation in early-stage breast cancer"],"prefix":"10.1007","volume":"33","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5622-8352","authenticated-orcid":false,"given":"Manabu","family":"Futamura","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yasuko","family":"Nagao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3395-3584","authenticated-orcid":false,"given":"Yukiko","family":"Takai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshimi","family":"Niwa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4427-6888","authenticated-orcid":false,"given":"Akira","family":"Nakakami","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mai","family":"Okawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2481-7739","authenticated-orcid":false,"given":"Yoshihisa","family":"Tokumaru","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3036-2412","authenticated-orcid":false,"given":"Junichi","family":"Mase","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryutaro","family":"Mori","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daichi","family":"Watanabe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3567-2187","authenticated-orcid":false,"given":"Takayuki","family":"Kinoshita","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nobuhisa","family":"Matsuhashi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,9,22]]},"reference":[{"key":"1775_CR1","doi-asserted-by":"publisher","first-page":"1233","DOI":"10.1056\/NEJMoa022152","volume":"347","author":"B Fisher","year":"2002","unstructured":"Fisher B, Anderson S, Bryant J, Margolese RG, Deutsch M, Fisher ER, et al. 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AN: Remuneration; Chugai and Eisai. JM: Remuneration: Chugai, Taiho, Pfizer, Eisai, Daiichi-Sankyo, AstraZeneca, and Eli Lilly. TK\u2014Remuneration: Chugai, Nippon-Kayaku, Pfizer, Exact Science, Daiichi-Sankyo, AstraZeneca, Intuitive, Covidien. NM\u2014Grants: Asahi Kasei, Chugai, Covidien, Daiichi-Sankyo, Eisai, e-NA Biotec, EP-CRSU, JMS, Johnson & Johnson, Kaken Pharm, Kyowa Kirin, MSD, Nippon Kayaku, Ono, ShiftZero, Taiho, TERUMO, Toray Medical. Remuneration: Abbott, Alfresa, AMCO, Asahi Kasei, Astellas, AstraZeneca, Bayer, Bristol-Myers, Chugai, Covideien, Daiichi-Sankyo, EP Pharma, Eisai, Eli Lilly, Guardant Health Japan, Gunze Medical, Intulent, Johnson & Johnson, Kaken, Kyowa Kirin, MC Medical, Merck, MSD, Novartis, Olympus, Ono, Striker, Taiho, TAKATA, Takeda, TERUMO, Tsumura, Viartis, Yakult, ZERIA.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"Formal consent was not required owing to the retrospective nature of the study.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}}]}}