Understanding Leukemia -- Diagnosis and Treatment

Medically Reviewed by Jennifer Robinson, MD on January 27, 2022
5 min read

Because many types of leukemia show no obvious symptoms early in the disease, leukemia may be diagnosed incidentally during a physical exam or as a result of routine blood testing. If a person appears pale, has enlarged lymph nodes, swollen gums, an enlarged liver or spleen, significant bruising, bleeding, fever, persistent infections, fatigue, or a small pinpoint rash, the doctor should suspect leukemia. A blood test showing an abnormal white cell count may suggest the diagnosis. To confirm the diagnosis and identify the specific type of leukemia, a needle biopsy and aspiration of bone marrow from a pelvic bone will need to be done to test for leukemic cells, DNA markers, and chromosome changes in the bone marrow.

Important factors in leukemia include the age of the patient, the type of leukemia, and the chromosomal abnormalities found in leukemia cells and bone marrow.

While the reported incidence of leukemia has not changed much since the 1950s, more people are surviving longer thanks mainly to advances in chemotherapy. Childhood leukemia (3 out of 4 cases in children is ALL), for example, represents one of the most dramatic success stories of cancer treatment. The five-year survival rate for children with ALL has risen to about 85% today.

For acute leukemia, the immediate goal of treatment is remission. The patient undergoes chemotherapy in a hospital and stays in a private room to reduce the chance of infection. Since acute leukemia patients have extremely low counts of healthy blood cells, they are given blood and platelet transfusions to help prevent or stop bleeding. They receive antibiotics to prevent or treat infection. Medications to control treatment-related side effects are given as well.

People with acute leukemia are likely to attain remission when chemotherapy is used as the primary treatment. To keep the disease under control, they will then receive consolidation chemotherapy for 1-4 months to get rid of any remaining malignant cells.

Patients with ALL will receive intermittent treatment usually for up to two years.

After obtaining a complete remission, some patients with acute myeloid leukemia (AML) may require an allogeneic stem cell transplant. This requires a willing donor with compatible tissue type and genetic characteristics -- preferably a family member. Other donor sources could include a matched unrelated donor or umbilical blood.

A stem cell transplant has three stages: induction, conditioning, and transplantation. First, the individual’s white blood cell count is brought under control by chemotherapy. Then a single dose of chemotherapy may be given followed by a conditioning regimen of high dose chemotherapy. This will destroy the individual’s bone marrow and any residual leukemia cells that may be present. Then the donor cells will be infused.

Until the donor marrow cells start producing new blood, the individual is left with virtually no blood cells -- white cells, red cells, or platelets. This makes death by infection or bleeding a strong possibility. Once the donor stem cells grow sufficiently into the marrow, usually in two to six weeks, long-term remission becomes a strong possibility. In addition to chemotherapy, the person will receive medication to prevent and treat graft versus host disease. With this disease, donor cells attack the person's normal tissue cells. Medication is also given to prevent rejection of the donor stem cells.

Allogeneic stem cell transplantation is both expensive and risky, but it offers the best chance for long-term remission for high risk AML and certain cases of ALL.

If these treatments don't work for kids and young adults that have B-cell type ALL, or the cancer comes back, their doctor may want to try a new kind of gene therapy. Using CAR T-cell therapy, certain immune cells can be "reprogrammed" to attack the cancer. Because there can be severe side effects, only certified hospitals and clinics can do this treatment.

Chronic lymphocytic leukemia (CLL), a form of leukemia that usually affects older persons, typically progresses slowly. Therefore, treatment may be conservative. Not all patients require immediate treatment. Patients experiencing symptoms requiring treatment include the so called ‘B’ symptoms of fevers, night sweats for 14 consecutive days, or 10% unintentional body weight loss over 6 months. Other symptoms, such as painful swollen lymph glands, painful swollen liver or spleen, or evidence of bone marrow failure, also require treatment.

Oral chemotherapy can effectively control symptoms of CML for several years. In the past, most cases of CML eventually advanced to an acute phase despite treatment, so doctors advised bone marrow transplantation during the chronic phase. Allogeneic stem cell transplantation for CML is still a treatment option for diseases resistant to treatment or for persons whose disease is in the acute phase.

The drug imatinib (Gleevec) has radically changed treatment for CML. Known as a molecular targeting drug, it attacks the genetic alterations that cause white blood cells to grow out of control. Gleevec doesn't cure CML, but it can result in long-term remission and survival of CML. This drug was shown to be superior to prior therapies such as busulfan, hydroxyurea, and interferon alpha. There are now five other drugs (asciminibbosutinib, dasatinib, nilotinib, and ponatinib) that can be used in CML if the leukemia becomes resistant to Gleevec. 

Nilotinib (Tasigna) has FDA approval for CML in the chronic phase. Dasatinib (Sprycel) is FDA-approved for first-line therapy of chronic phase CML. Bosutinib (Bosulif) and ponatinib (Iclusig) can be used during any phase of CML if a person is resistant to or cannot tolerate the other drugs. Still another drug, omacetaxine mepesuccinate (Synribo), is approved for those whose CML has progressed after treatment with two or more of the previous medications. Asciminib (Scemblix) can also be used after two or more of the previous medications have already been tried or if the person's cancer cells have a T315I mutation.