Supplementary Material for: A rare case of hemolytic anemia after alectinib that did not recur after switching to lorlatinib

We would like to share the case of a 55 year old male patient with ALK-positive lung cancer with a corpuscular hemolytic anemia following alectinib therapy. Approximately seven weeks after initiating alectinib therapy, this patient developed anemia. Laboratory tests revealed a new Coombs-negative hemolysis with adequate substrate levels, an increase in indirect bilirubin, reticulocytes and undetectable haptoglobin levels. Cytomorphology primarily showed numerous acanthocytes. This presentation aligns with a case reported in Japan, describing severe hemolytic anemia with morphological changes in erythrocytes under alectinib treatment. Notably, this is the first report describing a rapid increase in haemoglobin after pausing alectinib and no relapse of hemolysis after switching to lorlatinib, while the lung cancer remained stable (stable disease).