Leukemia Diagnosis and Screening
Leukemia patients referred to the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins are seen by a team of doctors who specialize in the disease. Hematologists, oncologists and pathologists examine the leukemia cells to define the specific type of leukemia to best plan treatment. A dedicated hematologic pathology division within our medical center has extensive expertise in the development and uses state-of-the-art technologies to accurately diagnose leukemia and lymphoma.
Doctors may identify leukemia during routine blood tests, before a patient has symptoms. If you already have symptoms and go for a medical visit, your doctor will perform a physical exam to check for swollen lymph nodes, spleen or liver. Your doctor also may order a variety of blood tests to evaluate the type and quantity of blood cells present. For example, a complete blood count measures the number of white blood cells, red blood cells and platelets. Leukemia causes a very high level of white blood cells, and may also cause low levels of platelets and hemoglobin, a protein in red blood cells that carries oxygen.
Other tests that can be used to diagnose leukemias include:
Bone Marrow Aspiration and Biopsy
A tissue sample taken from your hipbone or other large bone used to look for cancer cells. This is the only way to know whether leukemia cells are in your bone marrow. You will be given a local anesthetic to help reduce pain. Then, the doctor or nurse practitioner will insert a hollow needle to remove samples of bone marrow (called bone marrow aspiration) and a thicker hollow needle to remove a small piece of bone and bone marrow (bone marrow biopsy). The tissue will then be checked under a microscope for leukemia cells and will be tested for abnormal surface markers (“Flow cytometry”) and genetic markers.
Chest X-ray or Chest CAT scan
Can show swollen lymph nodes or other signs of leukemia or infection in your chest.
Cytogenetics – a lab test to look at the chromosomes (strands of DNA) of cells from samples of blood, bone marrow, or lymph nodes. If abnormal chromosomes are found, the test can show what type of leukemia you have. For example, people with CML have an abnormal chromosome called the Philadelphia chromosome.
A test in which your doctor may remove some cerebrospinal fluid (the fluid that fills the spaces in and around the brain and spinal cord). For this procedure, which takes about a half-hour and is performed with local anesthesia, the doctor uses a long, thin needle to remove fluid from the lower spine. You must lie flat for several hours afterward to keep from getting a headache. The lab checks the fluid for leukemia cells or other signs of problems.