EOD Primary Tumor
**Note 1:** Osseous (medullary) plasmacytomas (9731) are localized tumors occurring in the bone. There may be soft tissue extension.
**Note 2:** Extraosseous (extramedullary) plasmacytomas (9734) are plasma cell neoplasms that arise in tissues other than bone. The most common sites are the upper respiratory tract, the gastrointestinal tract, lymph nodes, bladder, central nervous system (CNS), breast, thyroid, testis and skin.
**Note 3:** Lymphoplasmacytic lymphoma (9671) and Waldenstrom Macroglobulinemia (9761) are now collected with the plasma cell disorders. These are systemic diseases and should always be coded 700.
**Note 4:** Per the 2016 WHO Hematopoietic and Lymphoid Neoplasms blue book, a plasmacytoma is defined as a single lesion. If there are multiple lesions/plasmacytomas, this is diagnostic of plasma cell myeloma (9732/3) and the Plasma Cell Myeloma Schema should be used to assign EOD.
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