Many cancer patients are at an increased risk of infection because of their low levels of infection-fighting white blood cells, a condition called neutropenia. The most common reason that cancer patients experience neutropenia is as a side effect of chemotherapy. Chemotherapy involves the use of drugs to destroy cancer cells. Chemotherapy works by destroying cells that grow rapidly, a characteristic of cancer cells. Unfortunately, chemotherapy also affects normal cells that grow rapidly, such as blood cells in the bone marrow, cells in the hair follicles, or cells in the mouth and intestines. Chemotherapy-induced neutropenia typically occurs 3-7 days following administration of chemotherapy and continues for several days before white blood cell levels return to normal. The type and dose of chemotherapy affects how low the white blood cell count drops and how long it will take to recover.

The dose and time schedule of chemotherapy drugs administered have been scientifically determined to produce the best chance of survival or cure. If you develop neutropenia, your doctors may have to delay your treatment or reduce the doses of your chemotherapy until your white blood cell counts have recovered. Clinical studies have shown that, for certain cancers, reducing the dose of chemotherapy or lengthening the time between treatments lowers cure rates compared to full-dose, on-time treatment. Fortunately, there are strategies for the prevention of chemotherapy-induced neutropenia that have been proven to reduce the incidence of fever, infection, admission to the hospital and allow you to receive your treatment on schedule.

Rather than waiting for infections to get out of control, work consciously to prevent infection. There are three components to preventing infection:

1. Protect yourself from infection
2. Recognize and report symptoms early
3. Ask your doctor about blood cell growth factors to reduce your risk of infection.

Protect Yourself

Most infections are caused by bacteria that are normally found in your body, especially in your mouth and GI tract and on your skin. Therefore, it is important to maintain good hygiene.

• Wash your hands frequently, especially before eating, after using the bathroom, or after touching animals.
• Clean your rectal area thoroughly. Report symptoms of irritation or tenderness, or problems with hemorrhoids.
• Take good care of your mouth and gums.
• Avoid cuts and skin wounds. Use an electric razor instead of blades to shave and use care when using sharp instruments such as needles, knives, or other tools.
• Clean cuts and scrapes with soap and water and apply an antiseptic.
• Don’t squeeze or scratch pimples
• Stay away from people who are ill with colds, flu, measles, chicken pox, or other contagious illnesses.
• Stay away from children who have recently had “live virus” vaccines. These include chicken pox and oral polio vaccines.
• Avoid animal waste, litter boxes, birdcages and fish tanks.
• Avoid standing water, as found in birdbaths, humidifiers, and flower vases.
• Wear gloves when gardening or cleaning up after others (especially small children).
• Don’t get any immunizations without checking with your doctor first.
• Don’t eat raw fish, seafood, meat, or eggs.

Recognize and Report the Symptoms of Infection Early

Infections are much easier to treat and manage when they are minor. For this reason, you should notify your doctor as soon as you notice any symptoms of infection.

There are two types of infection: systemic and local.

A systemic infection is usually caused by a bacteria or virus that circulates in the bloodstream. Therefore, symptoms of a systemic infection may present throughout the entire body. Examples of a systemic infection are a cold, a virus, the flu, mono, strep throat. Signs and symptoms of a systemic infection include:

• Fever
• Aches
• Chills
• Nausea
• Vomiting
• Weakness

A local infection is an infection in which the entire body is not infected, only a specific portion or the portion which is affected. An infected wound or cut would be an example of a local infection. Symptoms of a local infection are indicative to the site and include:

• Pain
• Redness
• Tenderness
• Swelling
• Pus
• Drainage with a foul odor
• Head near the site
• Fever

Reduce Your Risk: Blood Cell Growth Factors Increase White Blood Cell Counts

Chemotherapy-induced neutropenia can be prevented in most patients with the use of blood cell growth factors. Blood cell growth factors are naturally occurring substances that regulate certain critical functions in the body. They are responsible for stimulating cells in the bone marrow to produce more white blood cells.

The blood cell growth factors approved by the Food and Drug Administration for the prevention of chemotherapy-induced neutropenia are Neupogen® (filgrastim) and Neulasta® (pegfilgrastim). Multiple clinical trials have shown that Neulasta and Neupogen reduce the severity and duration of neutropenia associated with many kinds of chemotherapy regimens. The advantage that Neulasta provides over Neupogen is less frequent administration; it may be administered as a single dose for each chemotherapy cycle rather than daily, as is the requirement with Neupogen. Two clinical trials have shown that a single dose of Neulasta is as effective for managing neutropenia as an average of 11 daily injections of Neupogen. ^{1, 2}

¹ Vose J, Crump M, Lazarus H. Randomized, multicenter, open-label study of pegfilgrastim compared with daily filgrastim after chemotherapy for lymphoma. Journal of Clinical Oncology. 2003;21: 514-519.

² Green M, Koelbl H, Baselga J. A randomized double-blind multicenter phase III study of fixed-dose single-administration pegfilgrastim versus daily filgrastim in patients receiving myelosuppressive chemotherapy. Annals of Oncology. 2003:14:29-35.