Primary Myelofibrosis (PMF)

Classical PB shows a leuko-erythroblastic picture with teardrop-shaped erythrocytes.
Bone marrow aspiration often failes, and if any marrow is collected, hypocellularity is a key finding. Megakaryocytes, if present, can be clustered and may show abnormal chromatin (clumping) and altered nuclear-cytoplasmic ratio.

Diagnostic tabel for MPN