{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T06:04:56Z","timestamp":1790057096174,"version":"4.0.1"},"reference-count":30,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"\n Background<\/jats:title>\n Metaplastic breast carcinoma (MBC) is an uncommon invasive breast cancer subtype with marked morphological diversity. Many MBCs are managed within the triple-negative breast cancer (TNBC) framework, yet their clinical course may not mirror that of non-metaplastic TNBC. We therefore compared clinicopathological features, recurrence and metastatic patterns, and survival outcomes in patients with MBC and those with non-metaplastic TNBC.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n We reviewed 27 patients with pathologically confirmed MBC who were treated at the Cancer Hospital of Ningxia Medical University General Hospital from January 2015 to December 2023. From patients with non-metaplastic TNBC treated in the same period, 81 controls were randomly selected at a 1:3 ratio and matched by age and year of diagnosis. We assessed clinicopathological variables, immunohistochemical findings, treatment patterns, recurrence and metastasis, disease-free survival (DFS), and overall survival (OS). Survival was evaluated with Kaplan-Meier curves and log-rank tests.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n The two cohorts were comparable in age and menopausal status. Relative to TNBC, MBC more often presented as grade III disease (88.9% vs. 28.7%,\n P<\/jats:italic>\n \u00a0&lt;\u00a00.001) and T3\u2013T4 disease (33.3% vs. 11.1%,\n P<\/jats:italic>\n \u00a0=\u00a00.007), while nodal involvement was less common (25.9% vs. 51.9%,\n P<\/jats:italic>\n \u00a0=\u00a00.019). Proliferative activity was greater in MBC, with a higher Ki-67 index (54.0 \u00b1 16.3% vs. 43.5 \u00b1 22.0%,\n P<\/jats:italic>\n \u00a0=\u00a00.011) and a higher proportion of tumors with Ki-67 \u2265 30% (100.0% vs. 81.5%,\n P<\/jats:italic>\n \u00a0=\u00a00.020). During follow-up, recurrence or metastasis (25.9% vs. 8.6%, P\u00a0=\u00a00.041) and distant metastasis (22.2% vs. 2.5%, P\u00a0=\u00a00.003) occurred more often in MBC. DFS was numerically shorter in MBC but was not statistically different (\n P<\/jats:italic>\n \u00a0=\u00a00.200), whereas OS was significantly poorer (\n P<\/jats:italic>\n \u00a0=\u00a00.038).\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n In this matched cohort, MBC showed a profile of high-grade histology, greater tumor burden, active proliferation, limited nodal spread, and frequent distant metastasis. The results indicate that MBC should not be treated simply as another presentation of TNBC, but as a high-risk entity requiring careful assessment of metastatic risk.<\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fonc.2026.1932260","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T05:40:32Z","timestamp":1790055632000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Metaplastic breast carcinoma versus triple-negative breast cancer: distinct metastatic patterns and inferior overall survival in a matched retrospective cohort study"],"prefix":"10.3389","volume":"16","author":[{"given":"Rui","family":"Yang","sequence":"first","affiliation":[{"name":"The First Clinical Medical College, Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuelan","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncology, General Hospital of Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rui","family":"Chang","sequence":"additional","affiliation":[{"name":"The First Clinical Medical College, Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuang","family":"Ma","sequence":"additional","affiliation":[{"name":"The First Clinical Medical College, Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncology, General Hospital of Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dahai","family":"Chai","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncology, General Hospital of Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinping","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Surgical Oncology, General Hospital of Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,22]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"10","DOI":"10.3322\/caac.21871","article-title":"Cancer statistics, 2025","volume":"75","author":"Siegel","year":"2025","journal-title":"CA Cancer J Clin"},{"key":"B2","doi-asserted-by":"publisher","first-page":"15","DOI":"10.1016\/j.breast.2022.08.010","article-title":"Current and future burden of breast cancer: Global statistics for 2020 and 2040","volume":"66","author":"Arnold","year":"2022","journal-title":"Breast"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1038\/35021093","article-title":"Molecular portraits of human breast tumours","volume":"406","author":"Perou","year":"2000","journal-title":"Nature"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1016\/j.annonc.2021.06.023","article-title":"Customizing local and systemic therapies for women with early breast cancer: the St. Gallen International Consensus Guidelines for treatment of early breast cancer 2021","volume":"32","author":"Burstein","year":"2021","journal-title":"Ann Oncol"},{"key":"B5","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1186\/s13058-020-01353-z","article-title":"A comprehensive overview of metaplastic breast cancer: clinical features and molecular aberrations","volume":"22","author":"Reddy","year":"2020","journal-title":"Breast Cancer Res"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.5858\/arpa.2019-0396-ra","article-title":"Metaplastic breast carcinoma: update on histopathology and molecular alterations","volume":"143","author":"McMullen","year":"2019","journal-title":"Arch Pathol Lab Med"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1158\/1078-0432.ccr-21-3100","article-title":"Molecular characterization and prospective evaluation of pathologic response and outcomes with neoadjuvant chemotherapy in metaplastic triple-negative breast cancer","volume":"28","author":"Yam","year":"2022","journal-title":"Clin Cancer Res"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1634\/theoncologist.2017-0398","article-title":"Early and locally advanced metaplastic breast cancer: presentation and survival by receptor status in Surveillance, Epidemiology, and End Results (SEER) 2010-2014","volume":"23","author":"Schroeder","year":"2018","journal-title":"Oncologist"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2021.4123","article-title":"Clinical and demographic factors, treatment patterns, and overall survival associated with rare triple-negative breast carcinomas in the US","volume":"4","author":"Elimimian","year":"2021","journal-title":"JAMA Netw Open"},{"key":"B10","doi-asserted-by":"publisher","first-page":"1556","DOI":"10.3390\/cancers15051556","article-title":"Clinical characteristics and prognosis of metaplastic breast cancer compared with invasive ductal carcinoma: a propensity-matched analysis","volume":"15","author":"Lee","year":"2023","journal-title":"Cancers (Basel)"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1097\/01.pas.0000138183.97366.fd","article-title":"p63 expression in breast cancer: a highly sensitive and specific marker of metaplastic carcinoma","volume":"28","author":"Koker","year":"2004","journal-title":"Am J Surg Pathol"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1038\/s41379-018-0081-z","article-title":"Genomic profiling of metaplastic breast carcinomas reveals genetic heterogeneity and relationship to ductal carcinoma","volume":"31","author":"Krings","year":"2018","journal-title":"Mod Pathol"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1245\/s10434-018-6533-3","article-title":"Metaplastic breast cancer treatment and outcomes in 2500 patients: a retrospective analysis of a national oncology database","volume":"25","author":"Ong","year":"2018","journal-title":"Ann Surg Oncol"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1158\/1538-7445.sabcs15-p3-14-02","article-title":"Targeting the PI3K\/AKT\/mTOR pathway for the treatment of mesenchymal triple-negative breast cancer: evidence from a phase 1 trial of mTOR inhibition in combination with liposomal doxorubicin and bevacizumab","volume":"3","author":"Basho","year":"2017","journal-title":"JAMA Oncol"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1007\/s10549-019-05264-2","article-title":"Metaplastic breast cancer has a poor response to neoadjuvant systemic therapy","volume":"176","author":"Al-Hilli","year":"2019","journal-title":"Breast Cancer Res Treat"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1097\/md.0000000000002341","article-title":"Metaplastic breast carcinoma versus triple-negative breast cancer: survival and response to treatment","volume":"94","author":"Aydiner","year":"2015","journal-title":"Med (Baltimore)"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1007\/s10549-006-9301-1","article-title":"Metaplastic carcinoma of the breast, an unusual disease with worse prognosis: the experience of the European Institute of Oncology and review of the literature","volume":"101","author":"Luini","year":"2007","journal-title":"Breast Cancer Res Treat"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1186\/2162-3619-2-31","article-title":"Metaplastic breast cancer: histologic characteristics, prognostic factors and systemic treatment strategies","volume":"2","author":"Schwartz","year":"2013","journal-title":"Exp Hematol Oncol"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1245\/s10434-006-9124-7","article-title":"Characteristics and treatment of metaplastic breast cancer: analysis of 892 cases from the National Cancer Data Base","volume":"14","author":"Pezzi","year":"2007","journal-title":"Ann Surg Oncol"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1186\/1477-7819-11-129","article-title":"Unique clinicopathological features of metaplastic breast carcinoma compared with invasive ductal carcinoma and poor prognostic indicators","volume":"11","author":"Song","year":"2013","journal-title":"World J Surg Oncol"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1245\/s10434-020-09430-5","article-title":"Survival outcomes for metaplastic breast cancer differ by histologic subtype","volume":"28","author":"Tadros","year":"2021","journal-title":"Ann Surg Oncol"},{"key":"B22","doi-asserted-by":"publisher","first-page":"8","DOI":"10.1016\/j.breast.2019.10.003","article-title":"Comparison of outcomes between metaplastic and triple-negative breast cancer patients","volume":"49","author":"Polamraju","year":"2020","journal-title":"Breast"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1136\/jclinpath-2011-200586","article-title":"Metaplastic breast cancer: clinicopathological features and its prognosis","volume":"65","author":"Lee","year":"2012","journal-title":"J Clin Pathol"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.1016\/j.clbc.2017.04.009","article-title":"Metaplastic carcinoma of the breast is more aggressive than triple-negative breast cancer: a study from a single institution and review of literature","volume":"17","author":"El Zein","year":"2017","journal-title":"Clin Breast Cancer"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1158\/1078-0432.ccr-16-2857","article-title":"The landscape of somatic genetic alterations in metaplastic breast carcinomas","volume":"23","author":"Ng","year":"2017","journal-title":"Clin Cancer Res"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1038\/sj.onc.1210593","article-title":"Molecular signatures of metaplastic carcinoma of the breast by large-scale transcriptional profiling: identification of genes potentially related to epithelial-mesenchymal transition","volume":"26","author":"Lien","year":"2007","journal-title":"Oncogene"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1007\/s10549-011-1359-8","article-title":"The prognoses of metaplastic breast cancer patients compared to those of triple-negative breast cancer patients","volume":"126","author":"Bae","year":"2011","journal-title":"Breast Cancer Res Treat"},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.7150\/jca.40817","article-title":"Outcomes after treatment of metaplastic versus other breast cancer subtypes","volume":"11","author":"Moreno","year":"2020","journal-title":"J Cancer"},{"key":"B29","doi-asserted-by":"publisher","first-page":"96","DOI":"10.1038\/s41523-021-00302-z","article-title":"Poor response to neoadjuvant chemotherapy in metaplastic breast carcinoma","volume":"7","author":"Wong","year":"2021","journal-title":"NPJ Breast Cancer"},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.3389\/fonc.2021.593121","article-title":"The effect of post-mastectomy radiotherapy in patients with metaplastic breast cancer: a propensity score-matched analysis of the SEER database","volume":"11","author":"Hu","year":"2021","journal-title":"Front Oncol"}],"container-title":["Frontiers in Oncology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1932260\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T05:40:34Z","timestamp":1790055634000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1932260\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,22]]},"references-count":30,"alternative-id":["10.3389\/fonc.2026.1932260"],"URL":"https:\/\/doi.org\/10.3389\/fonc.2026.1932260","relation":{},"ISSN":["2234-943X"],"issn-type":[{"value":"2234-943X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,22]]},"article-number":"1932260"}}