Isochromosome 11q is Associated with Unique Characteristics and Poor Prognosis in Patients with Acute Myeloid Leukemia.

BACKGROUND: Isochromosome 11q in patients with acute myeloid leukemia is rarely reported, and little is known about its main features. METHODS: The presence of isochromosome 11q was identified in four patients (three adults and one child) from screening 441 patients with an acute myeloid leukemia diagnosis between 2009 and 2018 by using R-banding and fluorescence in situ hybridization. RESULTS: The child, patient 1 with unreported isochromosome (partial 11q isochromosome), accompanied with t(1;11) translocation, initially achieved remission after receiving chemotherapy. However, 4 months later this patient experienced a relapse. While multiple treatments were tried, it had no effect and the patient survived for 16 months. The remaining patients with isochromosome 11q exhibited numerical/structural chromosomal abnormal-ities involving myelodysplastic syndrome-related chromosomes 5, 7, 8, and 20. In patients 2 and 3, we found a derivative chromosome 21. Patient 3 was newly diagnosed with acute myeloid leukemia and was treated with many chemotherapy protocols, unfortunately with no effect. The patient then received traditional Chinese medicine and survived for 10 months, although she still has not achieved complete remission. Patients 2 and 4 received chemotherapy but experienced rapid disease progression and died within 2 months. CONCLUSIONS: In summary, patients with isochromosome 11q/partial 11q isochromosome have a poorer prognosis, especially for isochromosome 11q. Furthermore, these chromosome aberrations may be risk factors for the presence of isochromosome 11q or myelodysplastic syndrome-related genes, both of them may be associated with a failure to respond to treatment and poor outcomes. Hence, these discoveries may lay a foundation to study mechanisms and explore treatments.

Identification of chromosomal abnormalities and genomic features in near-triploidy/tetraploidy-acute leukemia by fluorescence in situ hybridization.

BACKGROUND: Near-triploidy/tetraploidy is rarely found in acute leukemia. Only limited data are available to characterize this condition, and it remains largely unknown. PATIENTS AND METHODS: In our study, we performed karyotype analysis on 1,031 patients diagnosed with acute leukemia from 2006 to 2018. A total of 10 patients of near-triploidy/tetraploidy karyotype were enrolled. Two cases of near-triploidy (66-79 chromosomes) and eight cases of near-tetraploidy (84-100 chromosomes) were identified. Bone marrow samples of these 10 patients were analyzed by fluorescence in situ hybridization with 19 commercially available probes that detected a small portion of gene alterations and large regions of chromosome amplifications. RESULTS: Of the six patients with acute myelocytic leukemia, we detected three cases of double t(8;21)(q22;q22) that have not been previously reported, and one of them demonstrated ins(21;8) (q22;q24q22). We also describe a novel pediatric case carrying double t(15;17)(q22;q21) and receiving targeted treatment with all-trans retinoic acid therapy. To date, this case has responded well to the regimen and has shown continuous complete remission. All patients received chemotherapy. One of them received allogeneic hematopoietic stem cell transplant (HSCT) and survived for 22 months. Eight of the 10 patients died, and the median overall survival was 11 months. CONCLUSION: Using fluorescence in situ hybridization, we identified the distinct complex karyotype of near-triploidy/tetraploidy and provided further prognostic information. Tetraploidy acute promyelocytic leukemia had favorable prognosis; thus, HSCT was not necessary. The case of insertion t(21;8)(q22;q24q22) in tetraploidy responded poorly to chemotherapy and achieved molecular remission with difficultly. Data from patients in this group indicated that near-triploidy/tetraploidy acute leukemia has poor prognosis and new therapy is urgently needed.