Are you having back pain with any of the following?

  • Severe pain, weakness or tingling in your leg(s).
  • Difficulty stopping urination or loss of control of bladder or bowels.
  • Unexplained fever, nausea or vomiting.
  • A history of cancer or unexplained weight loss.

We understand that you are experiencing one or more of the health issues that might be impacting your back pain.

We recommend that you discuss these health issues with your doctor before proceeding with this program.

Once you are cleared by your doctor to do this program, we hope it helps you find relief from your back pain.

Cancer Care

Fremont and San Leandro Medical Centers


Hairy cell leukemia is a rare and slow-growing cancer of the blood. It develops from an abnormal population of B lymphocytes, a white blood cell. Hairy cell leukemia is a type of chronic leukemia. As a “chronic” leukemia, hairy cell leukemia can sometimes take years or even decades to worsen to the point where symptoms develop and treatment is needed.

After the diagnosis is confirmed, we'll talk about treatment options and develop a management plan. Treatment options for hairy cell leukemia include watchful waiting, chemotherapy, targeted therapy, and immunotherapy

Watchful Waiting

Because hairy cell leukemia grows so slowly, immediate treatment may not be required, especially if you are not experiencing symptoms. This approach, known as watchful waiting, involves regular checkups to monitor blood cell counts and perform physical exams.

Treatment may be needed if blood cell counts begin to worsen or if you develop recurring infections or an enlarged spleen. In some cases, patients may live for decades without symptoms.

It is important to understand that watchful waiting is the best approach for some cases of hairy cell leukemia. Treating hairy cell leukemia too early does not offer any benefits and would expose you to unnecessary side effects of therapy.

We encourage you to talk with us about any concerns or fears you may have regarding watchful waiting.


Chemotherapy is commonly used to kill hairy cell leukemia cells. A common chemotherapy drug is known as a purine analog. These drugs are delivered through a vein or into a muscle. They work by interfering with the synthesis of new DNA, thereby preventing leukemia cells from multiplying.

Even if hairy cell leukemia comes back after initial treatment, a second round of chemotherapy is often very effective.

Side effects

Chemotherapy can cause a variety of side effects, the severity of which depends on the type and dose of the drug as well as the length of time it is given. You may experience 1 or more of the following side effects of chemotherapy with purine analogs:

  • Increased risk of infections (low white blood cell count)
  • Fevers
  • Fatigue (low red blood cell count)
  • Increased risk of bleeding (low platelet count)
  • Loss of appetite
  • Chills
  • Skin rash
  • Headache

Side effects associated with low blood cell counts are a special concern because it can make you vulnerable to infection. We may give you drugs to boost your white blood cell counts, antibiotics to prevent and treat infections, and transfusions of red blood cells and platelets. Removing an enlarged spleen may also help improve blood cell counts.

We have effective methods for preventing and managing chemotherapy side effects, which typically go away once treatment ends.

Targeted Therapy

Targeted therapy is a relatively new approach to treating cancer. It involves the use of drugs that target specific parts of the cancer cell that help it survive and grow.

In some cases, monoclonal antibody therapy can help fight hairy cell leukemia using your body’s own immune system. Monoclonal antibodies are immune system proteins made in a laboratory. These drugs are designed to target specific proteins on the cancer cell’s surface. When the drug attaches to the cancer cell, the immune response helps destroy the cell.

Side effects

Because targeted drugs take aim specifically at cancer cells, there is less collateral damage to healthy cells. But monoclonal antibody therapy is not without side effects, which may include:

  • Fever
  • Chills
  • Fatigue
  • Nausea
  • Rash
  • Headaches

We will watch you closely for these and other side effects. Notify us as soon as you notice symptoms.


In some cases, hairy cell leukemia may be treated with a drug called interferon, which is given as an injection. Interferon is a type of immunotherapy, which means it uses your immune system to fight the cancer.

This treatment option is usually reserved for hairy cell leukemia that does not respond to other therapies.

Side effects

Interferon causes symptoms similar to the flu. We can give you medicines to help treat side effects, which may include:

  • Fever
  • Chills
  • Fatigue
  • Muscle aches
  • Headaches

Measuring Response to Treatment

We periodically test your blood and bone marrow to check whether your leukemia is responding to treatment. Although treatment cannot cure hairy cell leukemia, it can put it into a complete remission. A complete remission means there are no signs of the disease in your blood and bone marrow, your spleen and other organs are normal size, and your blood cell counts have returned to normal.

Knowing how well your cancer responds to therapy helps us determine whether we should continue with your current treatment, increase the dose, or try another therapy that may be more effective.

Clinical Trials

We are always looking for new and better ways to treat hairy cell leukemia. Clinical trials are research studies that test new treatments or procedures that may prove better than standard treatments. We will talk with you about whether a clinical trial may be right for you.

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