Bone Marrow Evaluation

The bone marrow is responsible for producing red blood cells, white blood cells, and platelets. When blood work shows persistent or unexplained abnormalities, evaluating the marrow can help us understand whether blood cells are being produced correctly and whether cancer or another disease may be affecting that process.

At Pet Cancer Center, bone marrow evaluation is recommended only when the information it may provide could meaningfully clarify the diagnosis, assess the extent of disease, or influence treatment decisions.

A bone marrow evaluation involves collecting a small sample from the soft tissue inside a bone. Depending on the clinical question, this may include a bone marrow aspirate, which collects the marrow’s fluid and individual cells; a core biopsy, which preserves a small piece of tissue and structure; or both.

The samples are typically examined by a veterinary clinical pathologist. Evaluating the marrow alongside a current blood sample provides important context about how blood cells are developing and whether abnormalities are present.

Your pet's oncologist may recommend bone marrow evaluation when abnormalities or other diagnostic findings suggest that the marrow itself may be involved. Reasons may include:

• Unexplained or persistent anemia
• Low white blood cell or platelet counts
• Abnormal or immature cells in the bloodstream
• Changes affecting more than one type of blood cell
• Concern for leukemia, multiple myeloma, lymphoma, or another marrow-related cancer
• Evaluation of whether certain cancers have spread to the bone marrow
• The need for additional information before treatment begins

Bone marrow aspiration or biopsy may be particularly useful when a pet has a suspected or representative anemia or when routine testing has not identified the cause of abnormal blood cell counts.

Bone marrow samples are commonly collected from areas such as the upper leg, shoulder region, or pelvis. The most appropriate location depends on your pet's size, anatomy, and individual circumstances.

Heavy sedation or general anesthesia is typically needed so your pet remains still and comfortable while the sample is collected. The area is clipped and prepared, and a specialized needle is carefully introduced into the bone to collect the marrow sample.

Your oncology team will explain the procedure, preparation instructions, expected recovery, and any technical risks before moving forward.

Bone marrow examination can provide information about the number, appearance, and development of blood-forming cells. Depending on the findings, it may help identify:

• Abnormal production of red or white blood cells or platelets
• Cancerous cells within the marrow
• Marrow suppression or replacement
• Inflammation, infection, or other disease processes
• Whether additional or specialized testing may be useful

The findings are interpreted together with your pet's complete blood count, medical history, examination, imaging, and other diagnostic results. We will explain what the results mean, how confidently a diagnosis can be made, and what the findings mean for the options ahead.