Effects of the mass screenings for neuroblastoma in Japan. A study of 68 cases.

Sixty-eight cases of neuroblastoma detected during mass screening being performed by 11 local self-governing bodies of Japan were studied concerning age, clinical stage, and survival rate. Their average ages at the first screening, at the beginning of thorough examination, and at the start of therapy were 215.7, 245.6, and 264.7 days, respectively. This screening, which is aimed at the 6-month-old infants is considered to be acceptable, on the grounds that the majority of the cases (95.6%) were asymptomatic at the time of thorough examination, that for most of the cases (98.5%) the initiation of therapy was at under 1 year of age, and that their 60-month survival rate was 87.5%. However, there seems to be room for discussion of the best age at which subjects should be screened, because the 68 cases included some patients already with advanced stages at the time of thorough examination, and because "false negative cases" were identified besides the 68 positive cases.