Quantification improves the prognostic value of CD38 expression in B-cell chronic lymphocytic leukaemia.
Recent studies have shown that CD38 expressed as a percentage of the antigen positivity can predict prognosis and disease progression in patients with B-cell chronic lymphocytic leukaemia (B-CLL). The present study showed that quantification of CD38 expressed as antibody-binding capacity (ABC) improves the prognostic value of the percentage of CD38 positivity in B-CLL. In a cohort of 81 patients with B-CLL, a level of CD38 expression of > or = 30% and an ABC value of 250 proved statistically valid cut-off points to predict disease progression (% CD38: P=0.0027; ABC: P < 0.0001). There was a positive and significant correlation between the percentage of CD38 expression and ABC (r=0.7; P < 0.0001). There was a better discrimination of survival using ABC rather than percentage CD38 positivity (P < 0.0001 compared with P=0.0027). Only ABC predicted for survival in patients under 60 years of age (P=0.0076) or with stage A disease (P=0.0195). Both percentage CD38 and ABC discriminated between time to first treatment for all patients but only ABC predicted time to treatment for stage A patients (P=0.0004). In conclusion, CD38 positivity is an important prognostic factor in B-CLL. However, quantification of CD38 is superior to the percentage positivity and should be used clinically in conjunction with other variables of predictive value to identify B-CLL patients that are likely to progress.
Mainou-Fowler
Tryfonia
T
University Department of Haematology, School of Clinical and Laboratory Sciences, Royal Victoria Infirmary, Newcastle upon Tyne, UK. Tryfonia.Mainou-Fowler@ncl.ac.uk
Dignum
Helen
H
Taylor
Penelope R A
PR
Dickinson
Anne M
AM
Saunders
Peter W G
PW
Proctor
Stephen J
SJ
Summerfield
Geoffrey P
GP
D036541:ADP-ribosyl Cyclase / Q000378:metabolism*; D051997:ADP-ribosyl Cyclase 1; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000378:metabolism*; D000951:Antigens, Neoplasm / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D008297:Male; D008562:Membrane Glycoproteins; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate; D016896:Treatment Outcome
D015703:Antigens, CD; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D008562:Membrane Glycoproteins; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D051997:ADP-ribosyl Cyclase 1