LEVELS OF CAF7 (CD98) EXPRESSION CORRELATE WITH THE COMPLETE REMISSION DURATION IN CHILDHOOD ACUTE-LEUKEMIA

The levels of expression of the activation antigen CD98 were studied b y mAb CAF7 in 51 newly diagnosed consecutive cases of childhood acute lymphoblastic leukemia aged from 1 to 13 years. The mean follow-up was 8 months, A wide range of CAF7 expression was observed, the highest m ean fluorescence intensity exceeding the lowest by 20 times. No correl ation was revealed between CAF7 cell surface density on the one hand a nd sex, age, WBC, platelet count, LDH level, FAB groups and immunophen otypes on the other. A positive association between the levels of CAF7 expression and the complete remission (CR) duration was observed. The group of CAF7(low) patients had a significantly shorter CR duration c ompared to the CAF7(intermediate) and CAF7(high) cases (P = 0.0099). H alf of the CAF7(low) patients did not respond to the induction therapy and failed to achieve remission. These correlations were clearly mark ed in common ALL (GALL), which was usually considered to have a favora ble outcome. All CAF7(low) cALL cases had a significantly shorter CR d uration (P = 0.027), Thus CAF7 appears to provide additional informati on on the biological characteristics of childhood ALL and may have pro gnostic value regarding the response to therapy and remission duration .