What type of cancer is associated with a BCR-ABL translocation?

• A. Breast cancer
• B. Chronic Myeloid Leukemia (CML)
• C. Lung cancer
• D. Thyroid cancer

Answer: (B)

Chronic Myeloid Leukemia (CML) is specifically associated with the BCR-ABL translocation, which results from a genetic abnormality where parts of chromosome 9 and 22 switch places. This translocation creates a fusion protein that is constitutively active, leading to increased cell proliferation and reduced apoptosis.

This genetic alteration is a hallmark of CML and serves as a critical diagnostic marker for the disease. The presence of the BCR-ABL fusion gene not only aids in diagnosis but also directs the treatment approach, as targeted therapies, such as tyrosine kinase inhibitors, are designed to inhibit the activity of the BCR-ABL protein.

In contrast, the other types of cancer mentioned—breast cancer, lung cancer, and thyroid cancer—do not typically involve the BCR-ABL translocation and have different genetic and molecular characteristics that define their pathogenesis.