Yasumasa Sato

Effects of the mass screening of neuroblastoma in sapporo city

One hundred sixty‐seven cases of neuroblastoma in the Registry of Childhood Malignancies in Hokaido Prefecture from 1969 to 1984 were studied, using the age at diagnosis, the clinical stage at diagnosis, and the survival rate to assess the influence of the mass screening of neuroblastoma performed in Sapporo City since 1981. In Sapporo City, the capital of Hokkaido Prefecture, the condition of the three parameters improved significantly after the institution of mass screening had not yet been performed, no significant change was observed in any of the three parameters (48‐month survival rate changed only from 21.1% to 28.1%). Consequently, the improvement in Sapporo City was thought to be attributed to the effects of the mass screening.

Cases of neuroblastoma missed by the mass screening programs.

ABSTRACT: Twenty-two reported cases of neuroblastoma missed by the mass screening programs were reviewed (six cases in Sapporo City where a quantitative measurement for both vanillylmandelic acid (VMA) and homovanillic acid (HVA) is used and 16 cases in the districts of qualitative judgment only for VMA), and some potential factors for missing a patient were discussed. Most of the 22 patients were diagnosed over 12 mo and had advanced clinical stages at diagnosis (III or IV). Of the 17 cases whose outcome in prognosis was available, nine cases were dead and only three cases were alive without any trace of tumor. Fluctuation in the amounts of urinary VMA and HVA seemed to be one of the causes for missing a patient, especially with a small tumor. The comparison about tumor wt, VMA and HVA amounts, and clinical stage between the 22 true positive cases in Sapporo City and 46 ones in the districts of qualitative methods, and the difference in detection rate between the two groups suggested that the qualitative methods missed more patients with a small tumor. The patients who had abnormally high amounts of HVA with low amounts of VMA accounted for a fairly large part of the missed cases in Sapporo City as well as in the districts of qualitative methods. To the contrary, no patient of this type was found even among the 22 true positive cases in Sapporo City.

Incidence of neuroblastoma in Sapporo city.

The incidence of neuroblastoma in Sapporo City for the period before the enforcement of the mass screening of neuroblastoma (1974 to 1980) was compared with the period after it (1981 to 1987). No large difference was found in incidence between them. In 1981 to 1987 the occurrence cluster at 2 to 4 years of age found in the prescreening period disappeared and an accumulation of patients at 0 year of age was noted. The sensitivity of the mass screening was almost stable (76.9% to 80.0%) throughout the 7 years. By the mass screening system of Sapporo City, early detection will be expected in 60% to 70% of all the neuroblastoma patients, the deficiency of which is due to the patients who neglected the mass screening.

Mothers' Attitudes towards Children's Three-Year Health Examination

In the two health centers of Sapporo City, 112 mothers whose children participated in a three‐year health examination, and 107 mothers whose children did not, were interviewed about their childrens health.