Rare Acute Leukemias

While all acute leukemias are considered rare malignancies, the six acute leukemias discussed in this chapter are seen infrequently even in tertiary referral centers with large leukemia-focused programs. Three are rare leukemias associated with myeloproliferative neoplasms, two are rare subtypes of acute myeloid leukemia, and the last is a stem cell leukemia. These leukemias are often hard to diagnose accurately and all are considered difficult to treat. The following pages will highlight these rare leukemias and their associated diagnostic and therapeutic challenges.