What can cause hypercellular bone marrow?
Hypercellular bone marrow can be caused by conditions such as hematologic malignancies (e.g., leukemia, lymphoma), myeloproliferative disorders (e.g., polycythemia vera, essential thrombocythemia), bone marrow hyperplasia (e.g., recovery from anemia or infection), or infiltration by metastatic cancer cells. Further evaluation with bone marrow biopsy and additional testing is often needed to determine the underlying cause.