A 72 year old female is being treated for refractory acute promyelocytic anemia and is on day 16 of her chemotherapy regimen. On day 17, she collapsed and was found to be in torsades de pointes. What chemotherapeutic agent is the culprit?
Arsenic trioxide. It has an FDA approved indication for refractory or relapsed acute promyelocytic anemia. There are several case reports of patients being treated with arsenic trioxide for APL complicated by torsades de pointes.
Naito K et al. Two cases of acute promyelocytic leukemia complicated by torsade de pointes during arsenic trioxide therapy. Int J Hematol 2006; 83(4): 318-323. DOI: 10.1532/IJH97.05056