Trends in survival of childhood malignancy for the past three decades. I: Leukemia, malignant lymphoma, neuroblastoma, retinoblastoma and neoplasms of the urinary and digestive organs. The Committee for the Studies of the Treatments and the Biological Characteristics of Childhood Cancers.

Survival of some types of childhood neoplasms has improved considerably but remained poor for other types. Improvement in survival rate of common types of childhood neoplasms over the past three decades was assessed at the largest children's hospital in Japan. Using the data of the cancer registry of the hospital which recorded all the patients from 1965 to 1993, totalling 1026 cases, survival rate was analyzed for each type of neoplasm categorized by the S-classification for childhood neoplasms, a modification of the International Classification of Diseases. Survival was assessed for five 5 year periods from 1965 and a 4 year period from 1990-93. The 5 year survival rate for all neoplasms combined improved from 21.8% in the 1965-69 period to 73.3% in the 1985-89 period. Female patients' survival was better than male patients' in all periods. The improvement in survival rate was considerable for leukemia and malignant lymphoma, fairly good for neoplasms of the renal (mostly Wilms' tumor) and digestive (mostly hepatoblastoma) organs and moderate for neuroblastoma. Overall, survival rates of childhood neoplasms improved considerably. Much of this improvement was explained by a great improvement in survival rates of neoplasms of the blood which constituted the majority of patients.