Clinical features of different isoforms of PML鄄RARα fusion gene in patients with acute promyelocytic leukemia / 白血病·淋巴瘤

ABSTRACT

Objective To explore the clinical features and prognosis of different PML_RARα fusion gene isoforms in acute promyelocytic leukemia (APL). Methods The clinical data of 78 patients initially diagnosed with APL in Fujian Medical University Union Hospital from February 2013 to July 2016 were collected. The clinical features and prognosis of different PML_RARα fusion gene isoforms were analyzed. Results There were 32 females (41%) and 46 males (59%) in 78 patients, with a median age of 40 years old (13-68 years old). The most common PML_RARα fusion gene was L type (48.7%, 38/78), followed by S type (46.2%, 36/78) and V type (5.1%, 4/78). The patients with white blood cell count more than 10×109/L (high_risk) occurred mostly in S type (61.1%, 22/36), compared with V type and L type, and there were statistically different (χ 2 ＝ 7.683, P < 0.05). A total of 78 patients included 8 cases (10.2%) of combined CD34 positive, 17 cases (21.8%) of combined FLT3_ITD mutation, 12 cases (15.4%) of combined DNMT3A mutation and 9 cases (11.5%) of additional chromosomal abnormalities. There were no significant differences in CD34 positive, FLT3_ITD, DNMT3A, and the incidence of additional chromosomal abnormalities among the three different isoforms (P＞0.05). The most common occurrence of retinoic acid syndrome (RAS) during treatment was S type (21/36), while rare for L type and V type (χ2＝ 7.633, P< 0.05). There were no statistical differences in the complete remission (CR) rate and disease_free survival rate among the patients with different PML_RARα isoforms (P＞0.05). Conclusions The clinical characteristics of different PML_RARα fusion gene isoforms are different, including most_common L type, more_common V type and S type in high risk groups; complicated RAS is commonly found in S type during the treatment. And different isoforms have no effect on the CR and DFS rate.