Chronic myelogenous leukemia: The Daily PANCE Blueprint

The answer is E. The incidence of CML increases with age

CML is a myeloproliferative neoplasm characterized by the presence of the Philadelphia chromosome (BCR-ABL1 fusion gene), leading to uncontrolled myeloid cell proliferation. The incidence of CML increases with age, with a median age at diagnosis of approximately 64 years. While it can occur in younger individuals, it is significantly more common in older adults. Most patients are diagnosed in the chronic phase, which can progress to an accelerated or blast phase if untreated. First-line treatment involves tyrosine kinase inhibitors (TKIs) such as imatinib, which have dramatically improved survival outcomes.

Incorrect answer explanations:

• A. CML is associated with an absolute lymphocytosis – CML is a myeloproliferative disorder that leads to marked leukocytosis with neutrophilia and basophilia, not lymphocytosis. Chronic lymphocytic leukemia (CLL) is associated with absolute lymphocytosis.
• B. CML is more prevalent in females than males – CML has a slight male predominance with a male-to-female ratio of approximately 1.4:1.
• C. Most patients are diagnosed in the acute phase – CML is typically diagnosed in the chronic phase (85% of cases), which is asymptomatic or presents with mild symptoms. If untreated, it can progress to the accelerated or blast phase, which mimics acute leukemia.
• D. African American descent is associated with a poorer prognosis – There is no strong evidence that race significantly impacts prognosis. Instead, poor prognosis is linked to factors such as older age, symptomatic presentation, high WBC count, and presence of additional cytogenetic abnormalities.