A bone marrow biopsy is performed to assess which of the following?

• A. Marrow cellularity, fibrosis, and infiltration by malignant cells
• B. Peripheral blood lipid levels
• C. Renal function
• D. Lung capacity

Answer: (A)

Bone marrow biopsy directly samples the marrow to evaluate its hematopoietic tissue. It tells you how cellular the marrow is, whether there is fibrosis (scarring), and whether malignant cells are infiltrating the marrow. This information is crucial for diagnosing and staging disorders that affect the marrow’s production of blood cells, such as aplastic anemia (low cellularity), myelofibrosis (fibrosis), or leukemia/lymphoma involvement. Other tests that assess lipids, kidney function, or lung capacity measure systemic organ function, not the composition or infiltration of the marrow itself.