Hemolytic Anemia With Acanthocytes During Alectinib Treatment of Anaplastic T-Cell Lymphoma: A Case Report and Literature Review.

Alectinib, an ALK inhibitor used for ALK+ non-small cell lung cancer and other malignancies, has been associated with anemia and RBC abnormalities, including acanthocytosis. We report the first case of alectinib-induced acanthocytosis and hemolysis causing anemia during treatment for anaplastic large cell lymphoma in an 11-year-old boy. Extensive testing, including next-generation sequencing, and a specific indirect antiglobulin test conducted with alectinib, was performed to document this hemolytic anemia. Dose reduction improved hemoglobin levels, allowing completion of the 2-year treatment, suggesting a dose-dependent mechanism. Blood counts and morphology normalized after discontinuation of alectinib. A comprehensive literature review and discussion of the underlying mechanisms are also provided.