Basophils Unchained: A Rare Form of Leukemia

Primary Chronic Basophilic Leukemia (CBL) is an extremely rare disease and thus knowledge of this disease remains limited. There are no universal diagnostic criteria nor has the underlying pathogenetic mechanism been elucidated. In this peculiar case, we present a 93-year-old woman with an acute symptomatology of fatigue compounded by a manifest leukocytosis with 43% basophils in peripheral blood. The bone marrow aspirate also showed basophilia, 56% specifically. Interestingly, Next Generation Sequencing (NGS) on the bone marrow sample revealed three possible driver mutations, namely in the IDH2, DNMT3A, and BCOR gene. To date, NGS has never been performed on samples of patients with primary CBL. Our findings could be of great value in the search for the pathogenetic mechanism of this rare disease and to help find a successful treatment. Our patient was palliated with hydroxyurea to lower the white blood cells. Initially, this had a good effect, but unfortunately, she died two months after the diagnosis.