Tyrosine kinase inhibitors (TKI) used: sunitinib, sorafenib
Tumors being treated: metastatic renal cell carcinoma, malignant melanoma, hepatocellular carcinoma
Features:
(1) increased in red blood cell count and hemoglobin 1-2 weeks after the start of TKI therapy
(2) absence of stress erythrocytosis and dehydration
(3) absence of erythropoietin or other hematopoietic growth factor therapy
(4) absence of any increase in endogenous erythropoietin, with a mild decrease that was still within the normal reference range
(5) negative for JAK2V617F and for evidence of polycythemia vera
(6) absence of hypoxemia or significant pulmonary disease
(7) gradual decline in erythroid elements after discontinuation of TKI therapy
where:
• A more common adverse reaction to TKI therapy is moderate to severe anemia.