Molecular features of 109 patients with chronic myelomonocytic leukemia in a single center / 中华血液学杂志

Objective: To explore the molecular features of chronic myelomonocytic leukemia (CMML) . Methods: According to 2022 World Health Organization (WHO 2022) classification, 113 CMML patients and 840 myelodysplastic syndrome (MDS) patients from March 2016 to October 2021 were reclassified, and the clinical and molecular features of CMML patients were analyzed. Results: Among 113 CMML patients, 23 (20.4%) were re-diagnosed as acute myeloid leukemia (AML), including 18 AML with NPM1 mutation, 3 AML with KMT2A rearrangement, and 2 AML with MECOM rearrangement. The remaining 90 patients met the WHO 2022 CMML criteria. In addition, 19 of 840 (2.3%) MDS patients met the WHO 2022 CMML criteria. At least one gene mutation was detected in 99% of CMML patients, and the median number of mutations was 4. The genes with mutation frequency ≥ 10% were: ASXL1 (48%), NRAS (34%), RUNX1 (33%), TET2 (28%), U2AF1 (23%), SRSF2 (21.1%), SETBP1 (20%), KRAS (17%), CBL (15.6%) and DNMT3A (11%). Paired analysis showed that SRSF2 was frequently co-mutated with ASXL1 (OR=4.129, 95% CI 1.481-11.510, Q=0.007) and TET2 (OR=5.276, 95% CI 1.979-14.065, Q=0.001). SRSF2 and TET2 frequently occurred in elderly (≥60 years) patients with myeloproliferative CMML (MP-CMML). U2AF1 mutations were often mutually exclusive with TET2 (OR=0.174, 95% CI 0.038-0.791, Q=0.024), and were common in younger (<60 years) patients with myelodysplastic CMML (MD-CMML). Compared with patients with absolute monocyte count (AMoC) ≥1×10(9)/L and <1×10(9)/L, the former had a higher median age of onset (60 years old vs 47 years old, P<0.001), white blood cell count (15.9×10(9)/L vs 4.4×10(9)/L, P<0.001), proportion of monocytes (21.5% vs 15%, P=0.001), and hemoglobin level (86 g/L vs 74 g/L, P=0.014). TET2 mutations (P=0.021) and SRSF2 mutations (P=0.011) were more common in patients with AMoC≥1×10(9)/L, whereas U2AF1 mutations (P<0.001) were more common in patients with AMoC<1×10(9)/L. There was no significant difference in the frequency of other gene mutations between the two groups. Conclusion: According to WHO 2022 classification, nearly 20% of CMML patients had AMoC<1×10(9)/L at the time of diagnosis, and MD-CMML and MP-CMML had different molecular features.

Correlation between U2AF1 Gene Mutation Characteristics and Clinical Manifestations and Prognosis in Patients with Myelodysplastic Syndrome / 中国实验血液学杂志

OBJECTIVE@#To investigate the correlation between U2AF1 gene mutation and clinical manifestations and prognosis in patients with myelodysplastic syndromes (MDS).@*METHODS@#The clinical data of 203 MDS patients who accepted Next Generation Sequencing (NGS) was retrospectively analyzed in Nanfang Hospital, Southern Medical University from December 2012 to October 2019. According to whether the patients had U2AF1 gene mutation, the patients were divided into U2AF1 mutated group and non-mutated group, and the relationship between gene mutation characteristics and clinical manifestations and prognosis was analyzed. Then according to the difference of the mutation site of U2AF1, the patients in U2AF1 mutated group were divided into U2AF1@*RESULTS@#The incidence of U2AF1 mutation in MDS patients was approximately 11.3% (23/203), and the mutation frequency of U2AF1 allele was 32.5%. The male ratio in U2AF1 mutated group was significantly higher than that in U2AF1 non-mutated group (P=0.001). There was no patient who had complex karyotypes or TP53 gene mutation in U2AF1 mutated group. There were no significant differences in ages, blood parameters, bone marrow blasts, WHO 2016 classification, IPSS-R category, chromosomal abnormalities like del(5q), -7/del(7q), del(20q), +8, and gene mutation like ASXL1, DNMT3A, RUNX1, SF3B1, and SRSF2 mutation between U2AF1 mutated group and the non-mutated group. Compared with the non-mutated group, there was no significant difference in the overall survival time (P=0.377), the time of acute myeloid leukemia (AML) transformation (P=0.681), and the response rate to hypome- thylating agents in U2AF1 mutated group (P=0.556). Besides, no differences were observed in sex, diagnosis age, WHO 2016 classification, IPSS-R category, blood parameters, overall survival time, and AML transformation time between U2AF1@*CONCLUSION@#The U2AF1 gene mutation dose not affect the survival time, AML transformation time, and response rate to hypomethylating agents in MDS patients. Besides, there are no statistical differences in the clinical characteristics and prognosis of MDS patients between U2AF1