{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T05:24:46Z","timestamp":1787117086773,"version":"build-2736575974"},"reference-count":32,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T00:00:00Z","timestamp":1787097600000},"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":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Spindle cell metaplastic breast carcinoma (SpCC) is an uncommon subtype of metaplastic breast carcinoma. It often shows a triple-negative phenotype and can closely mimic malignant phyllodes tumor, primary breast sarcoma, and other spindle-cell lesions of the breast.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case presentation<\/jats:title>\n                    <jats:p>\n                      A 56-year-old woman presented with a 5.4-cm right breast mass. Core needle biopsy showed high-grade spindle cell carcinoma. The tumor expressed CKAE1\/AE3, CK8\/18, EMA, vimentin, TRPS-1, and partial GATA3, and was negative for ER, PR, HER2, p40, p63, CK5\/6, S-100, CD34, and ERG; the Ki-67 index was 85%. BRCA1\/2 testing showed no detectable mutation. After six cycles of albumin-bound paclitaxel plus carboplatin, ultrasound and MRI showed marked tumor regression. Modified radical mastectomy revealed residual degenerated malignant cells and ductal carcinoma\n                      <jats:italic>in situ<\/jats:italic>\n                      , with Miller-Payne grade 4 response and no metastasis in 17 axillary lymph nodes. The patient received postoperative radiotherapy and low-dose capecitabine. At the latest follow-up on June 25, 2026, there was no evidence of locoregional recurrence or distant metastasis.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This case supports a diagnosis-centered approach to SpCC, using spindle-cell morphology together with epithelial and breast-lineage markers and exclusion of key mimics. A platinum-taxane neoadjuvant regimen achieved a major pathological response in this patient, but evidence for SpCC remains limited and treatment should be individualized.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fonc.2026.1920800","type":"journal-article","created":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T04:35:41Z","timestamp":1787114141000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Spindle cell metaplastic breast carcinoma"],"prefix":"10.3389","volume":"16","author":[{"given":"Yanze","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Breast and Thyroid Surgery, Zibo Central Hospital","place":["Zibo, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyu","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Pathology, Zibo Central Hospital","place":["Zibo, Shandong, 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