Biological therapy is a treatment that uses drugs to improve the way your body’s immune system fights disease. Your immune system is your body’s natural defense against disease. A healthy and strong immune system can potentially detect the difference between healthy cells and cancer cells. Biological therapy attempts to strengthen and improve the immune system so that it can fight the cancer more effectively.

Interferon is the most common form of biological therapy. Interferons interfere with the division of cancer cells and can slow their growth. There are several types of interferons, and they are normally produced in the body. For the use of biological therapy, interferons are made in the laboratory. Other possible biological therapies include interleukin and monoclonal antibodies (MABs), such as Herceptin (combined with chemotherapy). New biological therapies recently approved by the FDA include:

  • Avastin (used in combination with paclitaxel for patients who have not received chemotherapy for metastatic breast cancer)
  • Lapatinib (used in combination with capecitabine (Xeloda) for metastatic breast cancer)

These newer therapies have shown great promise, but pose some medical risks. Discuss them with your doctor.

Most biological therapies are given by injection into a vein. They are frequently given in combination with chemotherapy or radiation therapy.

Side Effects

Possible side effects include:

  • Red, sore area where injection was given
  • Flu-like symptoms—fever, chills, gastrointestinal upset
  • Fatigue
  • Allergic reactions—cough, wheezing, skin rash
  • Confusion, disorientation, depression
  • Interleukin therapy is generally given in the hospital because it can cause severe changes in blood pressure.

Special Considerations

These treatments can cause extreme fatigue. It is important to get as much rest as possible when your body is fighting cancer. Talk with your doctor about how best you can minimize side effects and the discomforts that come with treatment.

To date, vaccines and other immunotherapies have not been effective in killing breast cancer. There is always hope that this may be effective in some patients, and scientists feel that the greatest benefit from vaccinations against breast cancer may be in those patients who have a predisposition to developing the disease (most likely related to a family history or a genetic mutation in a gene such as BRCA-1 or BRCA-2).