Bone marrow necrosis and rapidly progressive liver metastases after breast-conserving surgery in a 33-year-old woman with triple-negative breast cancer, followed by death 288 days after surgery: a case report.

BACKGROUND: Bone marrow necrosis (BMN) is rare, and malignancy-associated BMN often reflects high tumor burden, rapid progression, and poor prognosis. BMN after definitive treatment for early triple-negative breast cancer (TNBC), followed by visceral progression and coagulation-fibrinolytic abnormalities, is rarely reported.

CASE DESCRIPTION: A 33-year-old woman underwent breast-conserving surgery and sentinel lymph node biopsy for a 1.8 cm grade 3 invasive carcinoma of no special type. One of four sentinel nodes was positive (pT1cN1a, cM0); the surgical specimen was estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, human epidermal growth factor receptor 2 (HER2) 0, with Ki-67 approximately 90%, consistent with TNBC. She completed four cycles of epirubicin plus cyclophosphamide followed by four cycles of liposomal paclitaxel and adjuvant radiotherapy. Six days after radiotherapy, recurrent fever, bone pain, and progressive thrombocytopenia developed, followed by pancytopenia. Bone marrow biopsy on October 23, 2025 showed extensive necrosis with only a few degenerating nucleated cells and no clearly identifiable viable malignant cells. Contrast-enhanced computed tomography (CT) on November 21 showed liver metastases. On November 25, white blood cell count (WBC) was 1.9×109/L, hemoglobin 54.0 g/L, platelets 4×109/L, aspartate aminotransferase (AST) 308.9 U/L, total bilirubin 60.8 μmol/L, and lactate dehydrogenase (LDH) 2758.1 U/L. D-dimer was 19.49 mg/L, approximately 39 times the laboratory upper reference limit of 0.5 mg/L; prothrombin time (PT) was 15.3 s, below the documented upper reference limit of 21 s; and fibrinogen was 2.11 g/L. Retrospective application of the 2025 International Society on Thrombosis and Haemostasis (ISTH) overt disseminated intravascular coagulation (DIC) score yielded 5 points, meeting the scoring threshold. D-dimer later exceeded 40.00 mg/L, activated partial thromboplastin time (APTT) and thrombin time increased, and fibrinogen fell to 1.11 g/L. Hepatic and renal dysfunction and multiorgan failure ensued, and she died on December 2, 2025, 288 days after surgery.

CONCLUSIONS: In aggressive breast cancer, persistent fever, progressive bone pain, rapidly falling blood counts, and elevated LDH should prompt early evaluation for BMN and possible marrow involvement, with assessment for infection, coagulation disorders, hemophagocytic syndrome, and systemic progression. Marked thrombocytopenia with striking D-dimer elevation warrants dynamic DIC assessment even when PT remains within the local reference range. The temporal relationships among BMN, DIC, and prior therapy should be interpreted cautiously.