1.About 60%-85% of cases of anaplastic large cell lymphoma (ALCL) express anaplastic lymphoma kinase (ALK) fusion protein, which is caused by the breakapart of the ALK gene locus on chromosome 2 and fusion with other genes. The 5-year survival rate of patients with ALK gene fused with other genes (ALK positive) is much better than that of ALK negative patients (about 70% vs 30%), and the overall survival rate is much better than the latter.
2.Chromosomal translocation and ALK expression have been prescribed by WHO as one of the clinical diagnostic indicators of ALCL, and are the targets of the drug crizotinib.