When something goes wrong with blood cell production, answers are often found at their source: the bone marrow.
Bone marrow is the spongy tissue inside certain bones where blood cells are produced. Looking directly at the marrow can give healthcare professionals information that blood tests alone cannot provide. In systemic mastocytosis (SM), it can show if a type of white blood cell called mast cells have characteristic signs of the disease.
Bone marrow aspiration and biopsy are two procedures used to collect bone marrow samples for examination. But why does one tissue need two different procedures?
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One source, two samples: Understanding aspiration and biopsy
Bone marrow aspiration and biopsy are often performed together because they provide complementary information.
A bone marrow aspiration removes a small amount of liquid marrow and cells using a needle and syringe. The sample is then examined under a microscope and used for laboratory tests to evaluate the number, appearance and development of blood-forming cells.
A bone marrow biopsyBone marrow biopsy A procedure to collect a sample of bone marrow using a needle. Often used to examine the characteristics of mast cells and diagnose SM., on the other hand, removes a small core of bone marrow tissue using a special hollow needle. Because the tissue remains intact, the sample can show how cells are organized within the marrow and help identify changes such as scarring or abnormal cell infiltration.
Why two procedures?
Think of bone marrow like a mosaic, with its many tiles representing the bone marrow’s cells. An aspiration collects individual pieces so they can be examined closely, while a biopsy removes a small section of the mosaic with the pieces still arranged together.
Using the two procedures together allows healthcare professionals to see both what individual cells look like and how they are organized within the tissue.
Why you might need these tests in systemic mastocytosisMastocytosis Rare disease caused by the buildup of mast cells. Cutaneous mastocytosis primarily affects the skin and is more common in children, while systemic mastocytosis affects internal organs and is more common in adults.
Different conditions can cause characteristic changes in bone marrow cells or in how those cells are arranged. Looking at those characteristics can help healthcare professionals find the reason behind abnormal blood counts and diagnose or monitor conditions such as leukemia, lymphoma and multiple myeloma.
In SM, bone marrow testing can be used when blood tests for the KIT D816V mutation don’t find anything, but doctors still suspect SM. In these cases, the mutation can be tested for again using a bone marrow aspirate. The bone marrow has a much higher number of mutated mast cells than the blood, which makes the mutation easier for doctors to find.
A biopsy taken during bone marrow testing can also show whether mast cells are forming abnormal clusters, one of the key findings for diagnosing SM.
Besides supporting the diagnosis, bone marrow evaluation can also be used to determine which subtype of SM someone has. Features such as mast cellMast cell A type of white blood cell produced in the bone marrow. They help defend against infections and play a key role in allergic reactions. In SM, mast cells become overactive and build up throughout the body. burden, marrow dysfunction or an associated blood cancer can distinguish between SM subtypes. Diagnosing SM subtype is important because it determines the best treatment plan.
Read more about how KIT D816V mutation testing works
What to except if you need bone marrow aspiration and biopsy
Bone marrow aspiration and biopsy are typically performed during the same appointment.
First, they numb the area with a local anesthetic to make the procedure more comfortable. The aspiration is typically done first, then the biopsy. Doctors usually collect both samples from the back of the hip bone.
During aspiration, some people describe a brief, sharp or pulling pain, while the biopsy may feel more like pressure or a dull ache. Pain varies from person to person; talk to your doctor about additional pain relief or sedation if needed.
After the procedure, the site is covered with a bandage. Patients can feel mild soreness or tenderness for a few days. The healthcare team will give you instructions on how to care for the area and explain when to seek medical attention, such as if persistent bleeding, worsening pain, redness, swelling or a fever develops.
Learn more: “Diagnosing mastocytosis: Tips for recovering from a bone marrow biopsy”
About the results
The bone marrow samples will be sent to a laboratory for analysis. Some results may be available within a few days, while specialized tests can take longer. The healthcare provider will review the findings and explain what they mean for your diagnosis, treatment or ongoing monitoring.
