INCIDENCE OF CHILDHOOD ACUTE LYMPHOBLASTIC-LEUKEMIA (ALL) AND POPULATION-BASED TREATMENT RESULTS IN SWITZERLAND - EXPERIENCES WITH 507 STUDY AND 149 NONSTUDY PATIENTS

Of 656 patients with ALL (all types) diagnosed in Switzerland during 4 consecutive I-year periods (1976-1979, 1980-1983, 1984-1987, 1988-1991), 507 were officially registered on protocols (''study'' patients) while 149 were not (''nonstudy'' patients). The mean incidence of 3.8/100,000 children <15 years/year is higher than reported for other Western countries. Evidence is presented suggesting that the 656 patients represent only approximately 90% of all children with ALL residing in Switzerland, indicating that the true incidence of ALL might even be higher. The fraction of ''nonstudy'' patients fell from 40% (1976-1979) to 15% (1984-1987). The rate of survival at 4 years of all patients with ALL (''study'' and ''nonstudy'') increased by 17% du ri ng the th ree consecutive periods 1976-1979, 1980-1983, and 1984-1987. As expected, a higher increase (20%) was observed in ''study'' patients and a statistically nonsignificant lower one (10%) in ''nonstudy'' patients. (C) 1995 Wiley-Liss, Inc.