Coexisting Extra-Medullary Manifestation of Chronic Myelomonocytic Leukemia and Follicular Lymphoma What's Between Neoplastic Follicles Matters.

We illustrate a rare case of coexisting extramedullary manifestation of CMML and new onset follicular lymphoma within the same core-needle biopsy of a lymph node. We discuss the differences between extramedullary hematopoiesis and extramedullary manifestation of myeloid neoplasms. We also highlight the importance of generous tissue sampling and thorough examination of nodal tissue in the setting of an established myeloid neoplasm to avoid missing rare but possible nodal involvement.