Diagnosis

Doctors use many tests to diagnose cancer and determine if it has metastasized (spread). Some tests may also determine which treatments may be the most effective. For most types of cancer, a biopsy is the only way to make a definitive diagnosis of cancer. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Imaging tests may be used to find out whether the cancer has metastasized. 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

The following tests may be used to diagnose AML:

Blood tests. To diagnose AML, a doctor will do blood tests to count the number of white blood cells and to see if they look abnormal under the microscope. Special tests called flow cytometry (immunophenotyping) and cytochemistry are sometimes used to distinguish AML from other types of leukemia and to determine the exact subtype of AML. Chromosome studies called cytogenetics are used to identify genetic changes in the AML blasts, and these changes often help doctors decide the best course of treatment.

Genetic testing. An increasing number of genetic mutations in the AML cells are being identified that can help determine prognosis (chance of recovery), and these molecular analyses are now being done more often at the time of diagnosis.

Bone marrow biopsy. In a bone marrow biopsy, a doctor takes a sample of marrow, usually from the back of the hipbone, with a needle. The patient is given medication to numb the area beforehand. 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).

Lumbar puncture (spinal tap). A lumbar puncture is a procedure in which a doctor takes a sample of cerebral spinal fluid (CSF) to look for cancer cells, blood, or tumor markers (substances found in higher than normal amounts in the blood, urine, or body tissues of people with certain types of cancer). CSF is the fluid that flows around the brain and the spinal cord. Doctors generally give an anesthetic to numb the lower back before the procedure. The CSF is then examined under the microscope for the presence of AML cells.

Imaging tests. A computed tomography (CT or CAT) scan (test that creates a three-dimensional picture of the inside of the body) or magnetic resonance imaging (MRI, test that uses magnetic fields, not x-rays, to produce detailed images of the body) may be used to learn more about the cause of symptoms or to help diagnose infections in patients with AML. They are not regularly used for staging of AML since the disease is known to have spread throughout the bone marrow and blood at the time of diagnosis. These tests may not be done for every patient.

Learn more about what to expect when having common tests, procedures, and scans.

Find out more about common terms used during a diagnosis of cancer.