A bone marrow aspiration, biopsy, or both are done to

• Look for the cause of problems with red blood cells, white blood cells, or platelets in people who have conditions such as thrombocytopenia, anemia, or an abnormal white blood cell count.
• Find blood disorders, such as leukemia, certain anemias, or problems that affect the bone marrow, such as multiple myeloma or polycythemia vera.
• Check to see if a known cancer, such as Hodgkin's lymphoma or non-Hodgkin's lymphoma, has spread to the bone marrow. This is part of what is called staging. It is done to find out if the cancer has spread and how much it has spread. This helps plan cancer treatment.
• Find infections or tumors that may start in or spread to the bone marrow. If you have an infection, a culture and sensitivity test of the bone marrow sample may be used to find out which antibiotics will work best to treat the infection.
• Find the best treatment for a bone marrow problem. Once treatment has been started, a bone marrow aspiration and biopsy may be done to see if the leukemia cells are gone, which means the treatment is working.
• Collect a sample of bone marrow for medical procedures, such as stem cell transplantation or chromosomal analysis.