As you may already know, chemotherapy works by attacking the rapidly dividing cells it finds in the body, particularly cancer cells because they multiply quickly. However, chemotherapy can't differentiate between cancer cells and other rapidly dividing healthy cells, such as bone marrow cells. As a consequence, many chemotherapy patients, especially older patients, experience a drop in the levels of their blood cells, including their infection-fighting white blood cells.1,3,4 This may lead to the patient's chemotherapy being stopped or reduced until the white blood cell count recovers enough to resume treatment, which can give cancer cells a chance to grow. A low white blood cell count, a condition called neutropenia, may also increase a patient's risk of infection, which can lead to delays in treatment, or hospitalization.1,4-6

Chemotherapy-related infections may:

  • Delay chemotherapy treatment
  • Require changing the patient's chemotherapy dose
  • Require hospitalization, most commonly in the first and second chemotherapy cycles5,7

Older patients, due to normal body changes, are at greater risk than younger patients for a low white blood cell count and its complications.1,4 For example, the risk of infection is measurably greater in patients receiving chemotherapy with non-Hodgkin's lymphoma aged 65 and older than in younger patients. Not only are these complications more common in older patients, but when older patients are hospitalized to treat an infection, they tend to have longer hospital stays than younger patients.1,4,6

To help minimize the risk of such complications, older patients are more likely than younger patients to be given reduced doses of chemotherapy. However, studies indicate that full-dose, on-schedule treatments may improve outcomes, especially in the case of potentially curable tumors. This is important to know because older patients with cancer can respond as well to treatment as younger patients if they are given similar levels of chemotherapy.1,3

Fortunately, there are drugs called white blood cell boosters that can stimulate white blood cell production and help protect against infection caused by strong chemotherapy, and may help allow full-dose chemotherapy on schedule.1,4,6,8

References

  1. Repetto L. Greater risks of chemotherapy toxicity in elderly patients with cancer. J Supportive Oncol. 2003;1(2):18-24.
  2. Chemotherapy and you: A Guide to self-help during cancer treatment: Understanding chemotherapy. National Cancer Institute Web site. Available at: http://www.cancer.gov/cancertopics/chemot herapy-and-you/page2. Accessed December 8, 2004.
  3. Older patients with colon cancer benefit from chemotherapy. National Cancer Institute Web site. Available at: http://www.cancer.gov/clinicaltrials/results/older-patients-and-chemo1001. Accessed December 8, 2004.
  4. Osby E, Hagberg H, Kvaloy S, et al. CHOP is superior to CNOP in elderly patients with aggressive lymphoma while outcome is unaffected by Filgrastim treatment: results of a Nordic Lymphoma Group randomized trial. Blood. 2003 May 15;101(10):3840-8.
  5. Lyman GH, Delgado DJ. Risk and timing of hospitalization for febrile neutropenia in patients receiving CHOP, CHOP-R, or CNOP chemotherapy for intermediate-grade non-Hodgkin lymphoma. Cancer. 2003 Dec 1;98(11):2402-9.
  6. Rivera E, Erder MH, Fridman M, Frye D, Hortobagyi GN. First-cycle absolute neutrophil count can be used to improve chemotherapy-dose delivery and reduce the risk of febrile neutropenia in patients receiving adjuvant therapy: a validation study. Breast Cancer Res. 2003;5(5):R114-R120.
  7. Lyman GH, Morrison VA, Dale DC, Crawford J, Delgado DJ, Fridman M; OPPS Working Group; ANC Study Group. Risk of febrile neutropenia among patients with intermediate-grade non-Hodgkin's lymphoma receiving CHOP chemotherapy. Leuk Lymphoma. 2003 Dec;44(12):2069-76.
  8. Neulasta® (pegfilgrastim) prescribing information, Amgen.