Early Detection of t(8;21) Chromosomal Translocations During Treatment of PML-RARA Positive Acute Promyelocytic Leukemia: A Case Study

Early mortality in acute promyelocytic leukemia: Potential predictors

Acute promyelocytic leukemia (APL) is a rare leukemia characterized by the balanced reciprocal translocation between the promyelocytic leukemia gene on chromosome 15 and the retinoic acid receptor α (RARα) gene on chromosome 17, and accounts for 10-15% of newly diagnosed acute myeloid leukemia each year. The combined use of all-trans retinoic acid and arsenic trioxide (ATO) as primary therapy has markedly improved the survival rate of patients with APL. Mortality in the first 30 days following therapy remains a major contribution to treatment failure. In the present study, published data was reviewed with a focus on the factors associated with early mortality. When treated with ATO as a primary treatment, the fms-like tyrosine kinase-internal tandem deletion has no impact on early mortality. Low lymphoid enhancer binding factor-1 expression may be a reliable marker for early mortality and the target of therapy if it could be proven by further studies. Cluster of differentiation (CD)56+ and CD34+/CD2+ may be candidates to select high-risk patients. The risk of early mortality in APL still cannot be predicted via the cell surface makers, despite multiple studies on their prognostic significance. Typically, a complex translocation did not alter the survival rate in patients with APL; however, if an abnormal karyotype [e.g., Ide(17), ZBTB16/RARα and STAT5B/RARα] appeared singularly or as part of a complex mutation, there is a high possibility of early mortality if clinicians are unable to identify or monitor it.

Co-expression of t(15;17) and t(8;21) in a Case of Acute Promyelocytic Leukemia: Review of the Literature

Additional chromosomal abnormalities in acute myelogenous leukemia have been identified as one of the most important prognostic factors. Favorable chromosomal changes such as t(8;21), inv(16), and t(15;17) are associated with higher rates of complete remission and event-free survival. Translocation (15;17) characterizes acute promyelocytic leukemia (APL) (French-American-British class M3) in almost all patients. Secondary chromosomal abnormalities are also present in approximately 23%-29% of patients with newly diagnosed APL. The prognostic implications of t(8;21) and other secondary cytogenetic aberrations in APL are reviewed here. We present a 47-year-old woman diagnosed with APL whose initial cytogenetic analysis included both t(8;21) and t(15;17). The initial induction chemotherapy included 3 days of idarubicin (12 mg/m2/day) and daily all-trans retinoic acid (ATRA; 45 mg/m2/day). At the sixth week of treatment, a control bone marrow biopsy was found to be normocellular, t(15;17) bcr3 and t(8;21) were negative, and t(15;17) bcr1 fusion transcripts were reduced from 5007 (1.78525699%) copies per 1 µg RNA to 40 (0.00062020%) with real-time quantitative polymerase chain reaction. Consolidation with 4 days of idarubicin (5 mg/m2/day), ATRA (45 mg/m2/day for 15 days), and cytarabine (1 g/m2/day for 4 days) was then started. However, the patient became pancytopenic and had neutropenic fever after consolidation treatment. Unfortunately, she died 3 months after the time of APL diagnosis, due to acute respiratory distress syndrome-like respiratory problems and multiorgan dysfunction requiring respiratory support and hemodialysis.

Conflict of interest:None declared.