{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T18:32:28Z","timestamp":1789842748606,"version":"4.0.1"},"reference-count":10,"publisher":"BMJ","issue":"3","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2024,12,2]]},"published-print":{"date-parts":[[2025,3]]},"abstract":"<jats:p>Immune checkpoint inhibitors are a standard treatment for solid metastatic cancer and are now used as neoadjuvant therapy in early triple-negative breast cancer.<\/jats:p>\n               <jats:p>While haematological immune-related adverse events are known, acquired amegakaryocytic thrombocytopaenia (AAT) is a rare condition characterised by a complete absence of megakaryocytes, leading to severe thrombocytopaenia, with no standardised treatment available.<\/jats:p>\n               <jats:p>A patient in her early 60s presented with a low platelet count and was initially treated with high-dose methylprednisolone (1\u2009g daily) for suspected immune-mediated thrombocytopaenia, but this was ineffective. A bone marrow biopsy revealed a depletion of megakaryocytes.<\/jats:p>\n               <jats:p>The treatment was switched to eltrombopag, cyclosporine and tranexamic acid.<\/jats:p>\n               <jats:p>Despite low platelet levels, the patient successfully underwent bilateral mastectomy with supportive platelet transfusions.<\/jats:p>\n               <jats:p>Three weeks after starting eltrombopag and cyclosporine, her platelet count returned to normal. AAT in neoadjuvant treatment has not been previously reported, highlighting the need for interdisciplinary collaboration to address these challenges.<\/jats:p>","DOI":"10.1136\/bcr-2024-263434","type":"journal-article","created":{"date-parts":[[2025,3,19]],"date-time":"2025-03-19T16:21:56Z","timestamp":1742401316000},"page":"e263434","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Acquired amegakaryocytic thrombocytopaenia after treatment with immune checkpoint inhibitor as part of neoadjuvant treatment in a patient with bilateral breast cancer"],"prefix":"10.1136","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-4849-2547","authenticated-orcid":false,"given":"Vivi Quoc","family":"Nguyen","sequence":"first","affiliation":[{"name":"Department of Oncology, Odense University Hospital, Odense, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Louise","family":"Kristensen","sequence":"additional","affiliation":[{"name":"Department of Pathology, Odense University Hospital, Odense, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henrik","family":"Frederiksen","sequence":"additional","affiliation":[{"name":"Department of Haematology, Odense Universitetshospital, Odense, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2025,3,19]]},"reference":[{"key":"2025082704102342000_18.3.e263434.1","doi-asserted-by":"publisher","DOI":"10.1146\/ANNUREV-PATHOL-042020-042741"},{"key":"2025082704102342000_18.3.e263434.2","doi-asserted-by":"crossref","first-page":"1771","DOI":"10.1056\/NEJMc2203316","article-title":"Pembrolizumab in Early Triple-Negative Breast Cancer","volume":"386","author":"Ganguly","year":"2022","journal-title":"N Engl J 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risk factors and effect on survival","volume":"71","author":"Haddad","year":"2022","journal-title":"Cancer Immunol Immunother"},{"key":"2025082704102342000_18.3.e263434.7","doi-asserted-by":"crossref","first-page":"3594","DOI":"10.1182\/blood.2020009016","article-title":"Hematologic complications of immune checkpoint inhibitors","volume":"139","author":"Kroll","year":"2022","journal-title":"Blood"},{"key":"2025082704102342000_18.3.e263434.8","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1097\/CJI.0000000000000428","article-title":"Pembrolizumab-Induced Acquired Amegakaryocytic Thrombocytopenia and Successful Combination Treatment With Eltrombopag, Romiplostim and Cyclosporine: A Brief Communication","volume":"45","author":"Park","year":"2022","journal-title":"J Immunother"},{"key":"2025082704102342000_18.3.e263434.9","doi-asserted-by":"crossref","first-page":"53","DOI":"10.3960\/jslrt.20047","article-title":"Acquired amegakaryocytic thrombocytopenia after durvalumab administration","volume":"61","author":"Suyama","year":"2021","journal-title":"J Clin Exp Hematop"},{"key":"2025082704102342000_18.3.e263434.10","doi-asserted-by":"crossref","first-page":"514","DOI":"10.1093\/annonc\/mdx693","article-title":"A fatal allo- and immune-mediated thrombocytopenia with a PD-L1 inhibitor","volume":"29","author":"Leroy","year":"2018","journal-title":"Ann Oncol"}],"container-title":["BMJ Case 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