A Bone Marrow Biopsy Is Mandatory for a Diagnosis of Essential Thrombocythemia.

To the Editor I read with interest the article by Kato et al. describing a patient presenting with extending carotid artery thrombus associated with thrombocytosis (1). I am afraid that this article may be confusing, prompting readers to assume that a bone marrow biopsy is not mandatory for a diagnosis of essential thrombocythemia. In the patient described in this article, a bone marrow biopsy was necessary to exclude myeloid neoplasms other than essential thrombocythemia (2).

The author states that he has no Conflict of Interest (COI).