Evaluating the risk of late relapse in patients with acute lymphoblastic leukemia

This study aimed to investigate the occurrence and characteristics of late relapse in adult patients with acute lymphoblastic leukemia. 

This study concluded that late relapse in these patients is not uncommon and leads to better outcomes after relapse compared to early relapse. 

Late relapse is the return of leukemia which occurs over 3 years after complete remission (CR). CR is when all signs of cancer are gone. It is unusual for patients with acute lymphoblastic leukemia (ALL) to have a late relapse. However, it is important to evaluate the occurrence and characteristics of late relapse in adult patients with ALL. 

This study involved 1909 adult patients with ALL. Patients were followed up for relapse for an average of 96.5 months (around 8 years). 

92% of all patients achieved CR. 43.2% of patients who achieved CR, relapsed. Of those who relapsed, 91.3% relapsed within 3 years and 8.7% relapsed after that. Of the patients who relapsed after 3 years, the average time to relapse was 47 months. Relapse beyond 3 years occurred in 3.8% of all who achieved CR. The risk of relapse at 3 years was 40%. The risk of relapse at 5 years was 43% and the risk at 10 years was 45%.  

Of the patients who achieved CR, 11.7% underwent autologous transplants and 40.6% underwent allogeneic transplants. An autologous transplant involves using healthy cells from the patient. An allogeneic transplant involves using cells from a matched donor.  Of those who received an autologous transplant, 43.2% relapsed early and 3.4% relapsed late. Of those who received an allogeneic transplant, 13.2% relapsed early and 1.3% relapsed late.

The 5-year overall survival (OS) rate from relapse was 5.8% in early relapse patients and 20% in late relapse patients. 

This study concluded that late relapse in adults with ALL is not uncommon and leads to a better outcome after relapse compared to early relapse. 

This study was based on data from medical records. Relevant information might have been missing.