Periportal extramedullary hematopoiesis in a patient with primary myelofibrosis: A great mimicker of an infiltrating tumor in the liver.

Primary myelofibrosis (PMF) is a rare and progressive bone marrow cancer characterized by fibrosis, abnormal megakaryocyte proliferation, and impaired blood cell production. We present a case of a 65-year-old male diagnosed with accelerated PMF and periportal extramedullary hematopoiesis. Despite a history of stable myelofibrosis, the patient developed progressive hepatosplenomegaly and persistent anemia. Imaging studies, including MRI and CT scans, revealed periportal masses concerning for malignant infiltrative process. Subsequent biopsies confirmed the diagnosis of a sclerosing extramedullary hematopoietic tumor. Treatment included JAK2 inhibitor therapy, blood transfusions, and an eventual bone marrow transplant. This case highlights the complexities in diagnosing and managing PMF, particularly with rare complications like periportal extramedullary hematopoiesis, and underscores the importance of integrating radiological and pathological findings for optimal management.