#00066424

Staghorn megakaryocytes are markedly enlarged cells, measuring approximately 10–30 times the size of a mature red blood cell (RBC), with a relatively low nuclear-to-cytoplasmic ratio due to abundant cytoplasm. The nucleus is characteristically multilobulated, typically showing 6–10 lobes arranged in a distinctive staghorn-like configuration, and nucleoli are absent. The cytoplasm is abundant, dark bluish in color, and generally lacks granules, reflecting a mature morphology. These features are classically associated with Essential Thrombocythemia (ET), a myeloproliferative neoplasm, in which megakaryocytes appear as giant cells with hyperlobulated “staghorn” nuclei and are often found in dense clusters, accompanied by the presence of both small and large platelet clumps.