{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T09:47:21Z","timestamp":1782467241349,"version":"3.54.5"},"reference-count":31,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T00:00:00Z","timestamp":1782432000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T00:00:00Z","timestamp":1782432000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Asia-Pac J Clncl Oncology"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Neoadjuvant chemotherapy (NAC) exerts selective pressure on tumor biology, frequently altering the expression of ER, PR, and HER2 in residual disease. While guidelines mandate re\u2010biopsy to guide adjuvant therapy, whether these biomarker conversions represent a true prognostic deterioration or a manageable adaptation remains controversial. This study investigates the relative prognostic weight of biomarker conversion and proliferative dynamics (Ki\u201067) in determining patient survival.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively analyzed 338 patients with invasive breast cancer who had residual disease following standard NAC and curative surgery. Paired biomarker status (pre\u2010NAC vs. post\u2010NAC) for ER, PR, HER2, and Ki\u201067 was evaluated. Adjuvant therapy was adapted according to the residual tumor profile, including targeted therapy for patients acquiring HER2 positivity. Survival outcomes were analyzed using Cox regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Biomarker conversion was substantial, with conversion rates of 13.9% for ER, 18% for PR, and 27% for HER2. However, despite this high frequency of receptor conversion, changes in receptor status (loss or gain) did not translate into statistically significant differences in disease\u2010free survival (DFS) or overall survival (OS) (all\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&gt;\u00a00.05). In sharp contrast, Ki\u201067 dynamics emerged as the significant independent prognostic factor. Patients who converted from high\u2010to\u2010low proliferation (Ki\u201067\u00a0&lt;\u00a018%) achieved significantly superior DFS (HR: 0.45, 95% CI: 0.24\u20130.84,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0=\u00a00.011) and OS (HR: 0.36, 95% CI: 0.15\u20130.85,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0=\u00a00.020) compared to those with persistent high expression.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>While biomarker conversion is a frequent event in residual breast cancer, it does not compromise survival outcomes when adjuvant treatment is adjusted according to the post\u2010NAC immunohistochemical (IHC) profile. Instead, prognosis is predominantly driven by the tumor's proliferative response. These findings suggest that persistent high Ki\u201067, rather than biomarker conversion, should be the primary marker for escalating adjuvant therapy and risk stratification.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/ajco.70134","type":"journal-article","created":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T09:10:31Z","timestamp":1782465031000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ki\u201067 Dynamics and Biomarker Conversion as Prognostic Factors in Residual Breast Cancer"],"prefix":"10.1111","author":[{"given":"\u00d6mer Faruk","family":"El\u00e7i\u00e7ek","sequence":"first","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eyy\u00fcp","family":"\u00c7avdar","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u00d6zge","family":"Yal\u0131c\u0131","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ezel","family":"Gedik","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meltem","family":"\u00d6znur","sequence":"additional","affiliation":[{"name":"Department of Medical Pathology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Y\u0131ld\u0131z Garip","family":"Bilen","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u0130lker","family":"Karaduman","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Okan","family":"Avc\u0131","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erdo\u011fan","family":"Sel\u00e7uk \u015eeber","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology Faculty of Medicine Tekirdag Namik Kemal University  Tekirda\u011f Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,6,26]]},"reference":[{"issue":"3","key":"e_1_2_6_2_1","doi-asserted-by":"crossref","first-page":"480","DOI":"10.1093\/annonc\/mdv611","article-title":"Changes in Tumor Expression of HER2 and Hormone Receptors Status After Neoadjuvant Chemotherapy in 21,755 Patients From the Japanese Breast Cancer Registry","volume":"27","author":"Niikura N.","year":"2016","journal-title":"Annals of Oncology"},{"issue":"6","key":"e_1_2_6_3_1","first-page":"422","article-title":"Discordances in ER, PR and HER2 Receptors After Neoadjuvant Chemotherapy in Breast Cancer","volume":"37","author":"Van de Ven S.","year":"2011","journal-title":"Cancer Treatment Reviews"},{"issue":"4","key":"e_1_2_6_4_1","doi-asserted-by":"crossref","first-page":"436","DOI":"10.1016\/j.clbc.2023.03.002","article-title":"Conversion of ER and HER2 Status After Neoadjuvant Therapy in Chinese Breast Cancer Patients","volume":"23","author":"Bo J.","year":"2023","journal-title":"Clinical Breast Cancer"},{"issue":"4","key":"e_1_2_6_5_1","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1038\/s41416-024-02777-6","article-title":"A Population\u2010Based Study on Trajectories of HER2 Status During Neoadjuvant Chemotherapy for Early Breast Cancer and Metastatic Progression","volume":"131","author":"Boman C.","year":"2024","journal-title":"British Journal of Cancer"},{"issue":"9","key":"e_1_2_6_6_1","first-page":"991","article-title":"The ASCO\u2013CAP Guideline Update for HER2 Testing in Breast Cancer","volume":"147","author":"Schnitt S. J.","year":"2023","journal-title":"Archives of Pathology & Laboratory Medicine"},{"issue":"1","key":"e_1_2_6_7_1","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1056\/NEJMoa2203690","article-title":"Trastuzumab Deruxtecan in Previously Treated HER2\u2010Low Advanced Breast Cancer","volume":"387","author":"Modi S.","year":"2022","journal-title":"New England Journal of Medicine"},{"issue":"2","key":"e_1_2_6_8_1","doi-asserted-by":"crossref","first-page":"167","DOI":"10.4274\/ejbh.galenos.2022.2022-1-4","article-title":"Prognostic Value of Receptor Change After Neoadjuvant Chemotherapy in Breast Cancer Patients","volume":"18","author":"\u00d6zdemir \u00d6.","year":"2022","journal-title":"European Journal of Breast Health"},{"key":"e_1_2_6_9_1","doi-asserted-by":"crossref","DOI":"10.3389\/fsurg.2022.1037215","article-title":"Clinical Significance and Prognostic Value of Receptor Conversion After Neoadjuvant Chemotherapy in Breast Cancer Patients","volume":"9","author":"He Y.","year":"2023","journal-title":"Frontiers in Surgery"},{"issue":"1","key":"e_1_2_6_10_1","doi-asserted-by":"crossref","DOI":"10.1038\/s41598-024-64492-9","article-title":"Does Immunohistochemical Marker Conversion Affect Prognosis in Breast Cancer Receiving Neoadjuvant Chemotherapy?","volume":"14","author":"Uzun M.","year":"2024","journal-title":"Scientific Reports"},{"issue":"2","key":"e_1_2_6_11_1","doi-asserted-by":"crossref","first-page":"254","DOI":"10.1007\/s10147-015-0897-1","article-title":"Impact of Biomarker Changes During Neoadjuvant Chemotherapy for Clinical Response in Patients With Residual Breast Cancers","volume":"21","author":"Enomoto Y.","year":"2016","journal-title":"International Journal of Clinical Oncology"},{"issue":"1","key":"e_1_2_6_12_1","first-page":"20","article-title":"Receptor Discordances After Neoadjuvant Chemotherapy and Their Effects on Survival","volume":"24","author":"Tural D.","year":"2019","journal-title":"Journal of BUON"},{"issue":"1","key":"e_1_2_6_13_1","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1007\/s10549-008-0081-7","article-title":"Prognostic Significance of Ki67 Before and After Neoadjuvant Chemotherapy in Breast Cancer","volume":"116","author":"Jones R. 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H.","year":"2020","journal-title":"Journal of Clinical Oncology"},{"issue":"5","key":"e_1_2_6_17_1","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1159\/000521880","article-title":"Receptor Status After Neoadjuvant Therapy of Breast Cancer: Significance and Implications","volume":"89","author":"Shaaban A. 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A.","year":"2009","journal-title":"Clinical Cancer Research"},{"issue":"8","key":"e_1_2_6_29_1","doi-asserted-by":"crossref","first-page":"1274","DOI":"10.1038\/s41416-023-02403-x","article-title":"Pathological Complete Response, Category Change, and Prognostic Significance of HER2\u2010Low Breast Cancer Receiving Neoadjuvant Treatment: A Multicenter Analysis of 2489 Cases","volume":"129","author":"Zhu S.","year":"2023","journal-title":"British Journal of Cancer"},{"key":"e_1_2_6_30_1","doi-asserted-by":"crossref","DOI":"10.1016\/j.ejca.2023.112956","article-title":"Prognostic Implications of HER2 Changes After Neoadjuvant Chemotherapy in HER2\u2010Zero and HER2\u2010Low Breast Cancer","volume":"191","author":"Kang S.","year":"2023","journal-title":"European Journal of Cancer"},{"key":"e_1_2_6_31_1","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/j.humpath.2023.11.003","article-title":"HER2 Categorical Changes After Neoadjuvant Chemotherapy: A Study of 192 Matched Breast Cancers Including HER2\u2010Low Category","volume":"142","author":"Karakas C.","year":"2023","journal-title":"Human Pathology"},{"issue":"9","key":"e_1_2_6_32_1","doi-asserted-by":"crossref","first-page":"594","DOI":"10.3109\/07357907.2011.621913","article-title":"Hormonal Receptor Status in Breast Cancer Can be Altered by Neoadjuvant Chemotherapy: A Meta\u2010Analysis","volume":"29","author":"Zhang N.","year":"2011","journal-title":"Cancer Investigation"}],"container-title":["Asia-Pacific Journal of Clinical Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/ajco.70134","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/ajco.70134","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/ajco.70134","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T09:10:35Z","timestamp":1782465035000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/ajco.70134"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,26]]},"references-count":31,"alternative-id":["10.1111\/ajco.70134"],"URL":"https:\/\/doi.org\/10.1111\/ajco.70134","archive":["Portico"],"relation":{},"ISSN":["1743-7555","1743-7563"],"issn-type":[{"value":"1743-7555","type":"print"},{"value":"1743-7563","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,26]]},"assertion":[{"value":"2026-02-28","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-06-08","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-06-26","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"ajco.70134"}}