Diagnosis

Doctors use many blood and bone marrow tests to diagnose leukemia and to determine the extent to which it may have spread. Although a patient’s signs and symptoms may cause a doctor to suspect leukemia, it is diagnosed only by blood tests and/or bone marrow evaluations. Some tests may also determine which treatments may be the most effective. Your doctor may consider these factors when choosing a diagnostic test:

• Age and medical condition
  
  
• The type of cancer suspected
  
  
• Severity of symptoms
  
  
• Previous test results

In addition to a physical examination, the following tests may be used to diagnose T-cell leukemia:

Blood tests. A doctor will do a routine blood test called a complete blood count (CBC) to measure the counts of different types of cells in the blood. If the blood contains high levels of white blood cells, T-cell leukemia may be present.

Bone marrow biopsy. In a bone marrow biopsy, a doctor takes a sample of marrow, usually from the back of the patient’s hipbone, with a needle. The cells from the marrow, along with the cells from the blood, are analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease).

Immunophenotyping. Immunophenotyping is the examination of antigens (proteins that can induce an immune response), on the surface of the leukemic cells. Immunophenotyping allows the doctor to confirm the exact type of leukemia.

Cytogenetics. Cytogenetics is the examination of the leukemic cells for chromosomal abnormalities. It assists in confirming the diagnosis and may help the doctor determine the person’s prognosis (chance of recovery).

Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium (a special dye) is injected into a patient’s vein to provide better detail. A CT scan also shows enlarged lymph nodes or a swollen spleen.

Skin biopsy. A skin biopsy is a procedure in which a sample of skin tissue is removed and examined under a microscope to look for the presence and type of T cells in the skin.

To learn more about what to expect during common diagnostic tests, read Cancer.Net: Tests and Procedures.

To learn about the terms used in this section, read the Cancer.Net Feature: Cancer Terms to Know: Newly Diagnosed.