Case studyJuvenile myelomonocytic leukemia with prominent CD141+ myeloid dendritic cell differentiation

- Juvenile myelomonocytic leukemia with prominent CD141+ myeloid dendritic cell (MDC) differentiation is described.
- CD141+ MDCs are CD13-bright and partially CD1c+.
- This is the first description of CD141+ MDCs involvement in a neoplasm.
- Marked DC differentiation in a neoplasm suggests a myelodendritic or myelomonodendritic process.

SummaryMyeloid malignancies showing CD141+ myeloid dendritic cell (MDC) differentiation have not been documented. Here, we describe a patient with juvenile myelomonocytic leukemia in which a prominent CD141+ cell population was identified most consistent with CD141+ MDCs based on phenotypic similarity with normal CD141+ MDCs. Molecular studies demonstrated a KRAS mutation. The findings from the spleen and bone marrow are described. This is the first well-documented demonstration of CD141+ MDC differentiation of a hematopoietic neoplasm.