What is the relationship between neutropenia and chemotherapy?

From the Guidelines

Neutropenia is a common and potentially life-threatening side effect of chemotherapy. The relationship between neutropenia and chemotherapy is well-established, with chemotherapy-induced neutropenia being a major dose-limiting toxicity of cancer treatment 1.

Causes and Consequences of Neutropenia

• Chemotherapy can cause neutropenia by damaging the bone marrow, leading to a decrease in the production of white blood cells, including neutrophils 1.
• Neutropenia can increase the risk of infections, including febrile neutropenia, which can be severe and even life-threatening 1.
• Febrile neutropenia can lead to hospitalization, dose reductions, and treatment delays, which can compromise clinical outcomes 1.

Prevention and Management of Neutropenia

• The prophylactic use of colony-stimulating factors (CSFs) can reduce the risk, severity, and duration of neutropenia and febrile neutropenia 1.
• CSFs can enable the delivery of more intensive or dose-dense chemotherapy when indicated 1.
• The decision to use prophylactic CSFs should be based on the patient's risk of febrile neutropenia and the potential benefits and harms of treatment 1.
• Dose reduction or delay may be a reasonable alternative to CSF prophylaxis in some cases, particularly in patients with a low risk of febrile neutropenia or those who have experienced severe neutropenia or febrile neutropenia in the past 1.

Guidelines and Recommendations

• The American Society of Clinical Oncology (ASCO) recommends primary prophylaxis with CSFs in patients who have a high risk (≥20%) of febrile neutropenia based on patient-, disease-, and treatment-related factors 1.
• Secondary prophylaxis with CSFs is recommended for patients who have experienced a neutropenic complication from a prior cycle of chemotherapy 1.

From the Research

Relationship Between Neutropenia and Chemotherapy

• Neutropenia is a common side effect of chemotherapy, characterized by a decrease in neutrophil count, which can lead to an increased risk of infection [(2,3,4,5,6)].
• Chemotherapy-induced neutropenia (CIN) is associated with a range of complications, including febrile neutropenia, infection-related hospitalizations, and mortality [(2,4,5)].
• The severity and duration of CIN are directly related to the risk of infection, with longer durations of grade 3 or 4 CIN increasing the risk of infection-related hospitalization 5.

Chemotherapy Regimens and Neutropenia Risk

• Different chemotherapy regimens have varying levels of myelotoxicity, with some regimens being more likely to induce neutropenia than others [(2,6)].
• Cytotoxic agents, such as alkylating agents, antimetabolic agents, antineoplastic antibiotics, platinating agents, and plant-derived alkaloids, are associated with a higher risk of infection following neutropenia 6.

Management of Chemotherapy-Induced Neutropenia

• The use of myeloid growth factors, such as filgrastim and pegfilgrastim, can reduce the risk of neutropenic complications and facilitate the delivery of full-dose chemotherapy 4.
• Alternative dosing schemes and the addition of growth factor support may be strategies to consider in order to minimize the risk of neutropenia and its associated complications 2.

Patient-Specific Factors

• Patient age, sex, and weight can influence the risk of CIN, with elderly or underweight patients requiring particularly careful monitoring 6.
• Regular monitoring of serum biochemical and haematological changes is important in the management of disease and the prevention of neutropenia-related complications 3.