Patient Characteristics in CD 20⁺ and CD 20⁻ Adult Acute Lymphoblastic Leukemia (ALL): A Single Institution Analysis.

Targeted therapy is increasingly incorporated into the chemotherapy regimens of adult ALL. While the prognosis of BCR/ABL + (Philadelphia) ALL is well recognized; the significance of CD 20 postivity is unknown. We report the characteristics of 76 patients treated at Emory University between January 1999 and March 2005, divided into 2 groups based on CD 20 expression, as determined by flow cytometry. The CD 20+ patients presented with a higher WBC count and LDH, and lower platelet counts (table). In the CD 20+ group, 65% had pre B cell ALL and 8% had high grade B cell leukemia/lymphoma, whereas the CD 20- group consisted of 30% pre B cell ALL, 24% T cell ALL, and 10% had high grade leukemia/lymphoma. Of the 35 Ph+ ALL patients, 27 were CD20+ (20%) and 18 CD20- (51%). Patients were treated on clinical trials L20, ALL2, and more recently with the Hyper-CVAD regimen (n=32). Only 5 of the CD 20+ patients received rituximab in addition to chemotherapy. With a median follow-up of 320 days, 46% of patients in each group are alive, 35% and 38% relapsed in the CD 20+ and CD 20- group, respectively. In summary, we found that CD 20+ ALL patients present with higher WBC count and LDH, and a lower platelet count; although, due to our small sample size, these differences were not significant. Further follow up is needed to provide mature results on survival and remission.