Effects of Auer rod on prognosis in patients with freshly-diagnosed non-M3 type acute myeloid leukemia

To investigate the effects of Auer rod on the prognosis of newly-diagnosed non-M3 type acute myeloid leukemia (AML).

A retrospective cohort study was performed on 154 patients initially diagnosed as non-M3 type AML in our center from January 2012 to December 2019. According to the presence or absence of Auer rod in the bone marrow blasts, the patients were divided into Auer rod positive and negative groups. Their follow-up data were obtained from medical records and through telephone conversations with the enrolled patients. Clinical data were compared between the 2 groups, including gender, age, white blood cell (WBC) count, platelet (PLT) count, hemoglobin (Hb), lactate dehydrogenase (LDH), French-American-British (FAB) classification, percentage of blast cells in bone marrow, and cytogenetic risk stratification. Kaplan-Meier survival analysis and multivariate COX regression model were used to analyze the difference in outcome of time-events between the 2 groups.

As compared with the Auer rod negative group, the Auer rod positive group had higher proportion of M2 type (P<0.001) but lower proportion of M5 type (P=0.005) in FAB classification, lower percentage of bone marrow blasts (P<0.001), higher mutation frequency of WT1 gene (P=0.006), and lower mortality rate (P=0.008). The overall survival (OS) was significantly longer in the Auer rod positive group than the negative group (P=0.01). Multivariate COX regression analysis showed that Auer rod was an independent influencing factor for OS (HR=0.298, 95%CI: 0.104~0.853, P=0.024).

Auer rod is an independent prognostic factor of AML, and presents good prognostic value.