What to Expect During a Bone Marrow Biopsy

If your doctor has recommended a bone marrow biopsy, it helps to know the basic idea before the appointment. A biopsy removes cells or tissue so a pathologist can examine them. For a bone marrow biopsy, the sample comes from inside a bone and is taken with a needle.

Bone marrow can be examined cell by cell, which gives your care team information other tests cannot. That matters most for diagnosing blood cancers, such as leukemias and lymphomas, because those cancers start in the cells the marrow makes.

Marrow samples are often studied further with tests called cytogenetic analysis and immunophenotyping. These look closely at the cells, including their chromosomes and the markers on their surface. The results help your doctor see exactly what is happening and reach a diagnosis.

The sample usually comes from the hip bone. A small area of skin, and the surface of the bone underneath, is numbed with an anesthetic first. A special wide needle is then pushed into the bone and turned, to remove a small core of bone with the marrow inside it.

A bone marrow aspiration is often done at the same time. An aspiration uses a syringe on the needle to draw out liquid marrow rather than a solid core. The two samples show different things, so your team may want both.

Some biopsies use a sedative, a medicine that helps you relax, stay still, or sleep during the procedure. Others use local anesthesia, which takes away feeling in one small area of the body. Which one is used, or whether both are, depends on your procedure and your care team's approach. Ask ahead of time, so you know what comfort measures will be in place.

Your sample goes to a pathologist, a doctor who examines tissue and fluid samples under a microscope. The pathologist studies it, sometimes alongside cytogenetic analysis and immunophenotyping. They then describe what they find in a document called a pathology report. Your doctor uses that report to explain your results and your next steps.

Waiting for a pathology report can be one of the harder parts of this, emotionally. It helps to ask your care team roughly how long results usually take, and who will go over them with you. Then you have a sense of the timeline instead of an open-ended wait.

Before your biopsy, ask what comfort measures will be used. Ask which tests will be run on your sample. Ask roughly when results should come back. Clear answers ahead of time can make the day of the procedure feel much more manageable.

• Call 911 or go to an emergency department if the puncture site keeps bleeding despite ten minutes of firm pressure, soaks through the dressing, or swells fast into a firm lump. Heavy bleeding after this test is rare, but it is not something to sit out at home.
• Call your care team straight away, at any hour, if your temperature reaches 100.4°F (38°C) or higher and you are having chemotherapy. The CDC treats fever during cancer treatment as a medical emergency. If you cannot reach them quickly, go to an emergency department and say you are on chemotherapy.
• Call your care team the same day if you run a fever at any other time, or the skin around the site turns hot, red or begins to ooze. A little oozing on day one is expected; a spreading red patch is not.
• Call your care team within a day or two if soreness at the site keeps building over the days afterward instead of easing off, or a sedative leaves you feeling groggy or unsteady well beyond the day of the test.

Sources for this section: MedlinePlus — Bone Marrow Biopsy, CDC — Fever and Cancer Treatment and NCI — Infection and Neutropenia During Cancer Treatment.