Therapy-related acute promyelocytic leukemia: a systematic review

The incidence of therapy-related acute promyelocytic leukemia (t-APL) is apparently rising. We systematically reviewed the English literature until March 15, 2013, and collected a total of 326 t-APL cases, with the following results: (1) t-APL affects predominantly middle-aged adults with a median age at diagnosis of 47 years and a female-to-male ratio of 1.7:1; (2) after an incidence peak at 2 years following the completion of treatment for the primary antecedent disease, the risk of developing t-APL quickly diminishes with time; (3) the four most common primary antecedent conditions are breast cancer, hematological malignancies, multiple sclerosis, and genitourinary malignancies; (4) topoisomerase II inhibitors and radiation represent the most common potential risk factors; (5) despite different DNA damage "hot spot" sites, t-APL has no significant clinicopathologic differences from de novo APL (dn-APL); (6) t(15;17) is the sole cytogenetic abnormality in the vast majority of patients; (7) only a small minority of cases have a myelodysplastic or pancytopenic preleukemic phase; (8) more than one-third of patients come to medical attention incidentally (i.e., due to laboratory abnormalities), while the most common symptom is mucocutaneous bleeding, and 79 % have clinical DIC; and (9) the remission rate of t-APL is about 80 %, similar to dn-APL.