TY - JOUR
T1 - Modulation of CD20 antigen expression after rituximab treatment
T2 - A retrospective study in patients with chronic lymphocytic leukemia
AU - D'Auria, Fiorella
AU - Guariglia, Roberto
AU - Villani, Oreste
AU - Mansueto, Giovanna
AU - Grieco, Vitina
AU - Zonno, Antonia
AU - Bianchino, Gabriella
AU - Di Giovannantonio, Luigina
AU - Vita, Giulia
AU - Musto, Pellegrino
PY - 2010/10
Y1 - 2010/10
N2 - Background: CD20 antigen down-modulation by anti-CD20 rituximab treatment is a well-recognized phenomenon in patients with non-Hodgkin's lymphoma. However, few data are currently available on this topic in other lymphoproliferative disorders, in particular in chronic lymphocytic leukemia (CLL).Objective: The aim of this study was to establish how many patients with CLL show a disappearance of CD20 antigen after salvage treatment with rituximab and its possible clinical significance.Methods: We sequentially analyzed CD20 expression by flow cytometry in patients treated with rituximab in combination with other agents for relapsed/resistant disease.Results: Eleven white patients with CLL (6 females, 5 males; median age, 71.6 years [range, 60-84 years]) were included in the study. Three of the 11 patients were not positive for CD20 due to complete response at baseline. Four of the remaining 8 patients (50%) lacked CD20 antigen on neoplastic cells after monoclonal antibody treatment. Two of them developed Richter's syndrome and died within 4 months. The phenomenon was transient in the other 2 patients, who were alive after a follow-up of 25 and 26 months, respectively, with CD20-positive recurrent disease.Conclusions: In this study, CD20 antigen disappearance in patients with CLL treated with rituximab-containing salvage regimens occurred in 4 of 8 (50%) tested patients, half of whom developed Richter's syndrome. [Note: Since the initial writing and submission, a third patient developed Richter's syndrome.] In 2 patients (50%), CD20 returned at progression.
AB - Background: CD20 antigen down-modulation by anti-CD20 rituximab treatment is a well-recognized phenomenon in patients with non-Hodgkin's lymphoma. However, few data are currently available on this topic in other lymphoproliferative disorders, in particular in chronic lymphocytic leukemia (CLL).Objective: The aim of this study was to establish how many patients with CLL show a disappearance of CD20 antigen after salvage treatment with rituximab and its possible clinical significance.Methods: We sequentially analyzed CD20 expression by flow cytometry in patients treated with rituximab in combination with other agents for relapsed/resistant disease.Results: Eleven white patients with CLL (6 females, 5 males; median age, 71.6 years [range, 60-84 years]) were included in the study. Three of the 11 patients were not positive for CD20 due to complete response at baseline. Four of the remaining 8 patients (50%) lacked CD20 antigen on neoplastic cells after monoclonal antibody treatment. Two of them developed Richter's syndrome and died within 4 months. The phenomenon was transient in the other 2 patients, who were alive after a follow-up of 25 and 26 months, respectively, with CD20-positive recurrent disease.Conclusions: In this study, CD20 antigen disappearance in patients with CLL treated with rituximab-containing salvage regimens occurred in 4 of 8 (50%) tested patients, half of whom developed Richter's syndrome. [Note: Since the initial writing and submission, a third patient developed Richter's syndrome.] In 2 patients (50%), CD20 returned at progression.
KW - CD20 expression
KW - Chronic lymphocytic leukemia
KW - Non-Hodgkin's lymphoma
KW - Rituximab
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U2 - 10.1016/j.clinthera.2010.10.005
DO - 10.1016/j.clinthera.2010.10.005
M3 - Article
C2 - 21095486
AN - SCOPUS:78649348230
SN - 0149-2918
VL - 32
SP - 1911
EP - 1916
JO - Clinical Therapeutics
JF - Clinical Therapeutics
IS - 11
ER -