Acute Lymphoblasic Leukemia |
The Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL) includes the former France-Belgium Group for Lymphoblastic Acute Leukemia in Adults (LALA), the French Western-Eastern Group for Lymphoblastic Acute Leukemia (GOELAL), and the Swiss Group for Clinical Cancer Research (SAKK)
Correspondence: Dr Sébastien Maury, Service dHématologie Clinique, CHU Henri Mondor, 51 av. du Mal de Lattre de Tassigny, 94010 Créteil cedex, France. Tel +33.149.812057, Fax +33.149.812067. E-mail: sebastien.maury{at}hmn.aphp.fr or Dr Marie-Christine Béné, Immunology Laboratory, CHU Nancy & Nancy Universite, 9 Allée du Morvan, 54500 Vandoeuvre les Nancy, France. Tel +33.383.157615, Fax +33.383.157660. E-mail: bene{at}medecine.uhp-nancy.fr
The prognostic significance of CD20 expression in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) has been mostly studied in children and yielded conflicting results. In 143 adults with Philadelphia chromosome-negative BCP-ALL treated in the multicentric GRAALL 2003 trial, CD20 positivity over 20% was observed in 32% of patients. While not influencing complete remission achievement, CD20 expression was associated with a higher cumulative incidence of relapse (CIR) at 42 months (P=0.04), independently of the ALL high-risk subset (P=0.025). Notably, the negative impact of CD20 expression on CIR was only observed in patients with a white blood cell count (WBC) over 30x109/L (P=0.006), while not in those with a lower WBC. In the former subgroup, this impact translated into lower event-free survival (15% vs. 59% at 42 months, P=0.003). CD20 expression thus appears to be associated with a worse outcome, which reinforces the interest of evaluating rituximab combined to chemotherapy in CD20-positive adult BCP-ALL. ClinicalTrials.gov ID, NCT00222027.
Key words: CD20, acute lymphoblastic leukemia, rituximab, prognosis.