Can chemotherapy cause anemia?

Can Chemotherapy Cause Anemia?

Yes, chemotherapy is a significant and well-established cause of anemia in cancer patients, directly impairing bone marrow production of red blood cells and, with certain agents like platinum-based drugs, reducing kidney production of erythropoietin. 1

Mechanisms of Chemotherapy-Induced Anemia

Chemotherapy causes anemia through two primary pathways:

• Direct bone marrow suppression: Chemotherapeutic agents directly impair hematopoiesis, including the synthesis of red blood cell precursors in the bone marrow 1, 2
• Nephrotoxic effects: Certain cytotoxic agents (particularly platinum-containing drugs like cisplatin) damage the kidneys, leading to decreased renal production of erythropoietin 1, 2, 3

Prevalence and Risk Patterns

The incidence of chemotherapy-induced anemia is substantial and increases progressively:

• Overall prevalence: Approximately 54% of cancer patients develop anemia during chemotherapy, with 39% experiencing mild anemia, 14% moderate anemia, and 1% severe anemia 4
• Cumulative effect: Anemia rates increase dramatically with repeated cycles—from 19.5% in cycle 1 to 46.7% by cycle 5 in the European Cancer Anemia Survey 1, 4
• High-risk malignancies: Lung cancer patients have the highest incidence at 71%, followed by gynecologic malignancies at 65% 4, 5

Regimens Most Likely to Cause Anemia

Platinum-based chemotherapy regimens carry the highest risk due to combined bone marrow and kidney toxicity 1:

• Commonly used in lung, ovarian, and head and neck cancers 1
• Cisplatin-based combinations cause more pronounced hemoglobin decline compared to non-cisplatin regimens (p < 0.001) 5
• The severity of anemia worsens with each successive cycle as myelosuppressive effects accumulate 1

Clinical Evaluation Thresholds

When to evaluate for anemia:

• Hemoglobin ≤ 11 g/dL should prompt evaluation 4
• Decrease of ≥ 2 g/dL from baseline, even if above 11 g/dL, warrants assessment 1, 4
• Nadir hemoglobin timing: Typically occurs around 2 weeks post-chemotherapy, though this varies 1

Important Clinical Pitfalls

Do not assume all anemia in chemotherapy patients is solely chemotherapy-induced. Cancer patients often have multifactorial anemia:

• Many patients present with pre-existing anemia before starting chemotherapy—44% of breast cancer patients, 68% of ovarian cancer patients, and 82% of lymphoma patients already have anemia at diagnosis 1, 5
• Evaluate for hemorrhage, hemolysis, nutritional deficiencies (iron, B12, folate), renal insufficiency, and bone marrow infiltration by tumor 1
• Iron studies (ferritin, transferrin saturation) should accompany evaluation, as functional iron deficiency commonly develops during chemotherapy 1

FDA-Approved Treatment Context

The FDA mandates that erythropoiesis-stimulating agents (ESAs) should only be used to treat anemia from myelosuppressive chemotherapy and must be discontinued once chemotherapy is complete 6. ESAs are contraindicated when the anticipated treatment outcome is cure, as they may increase tumor progression risk 1, 6.