Age-related profile of neuroblastoma: a comparison of tumors detected by mass-screening with those detected clinically.

Infants with neuroblastoma are known to have a favorable prognosis compared to those over 1 year of age. However, there is little biological information about the age-related heterogeneity of neuroblastoma. We evaluated the biological profile comparing cases detected by mass screening with those detected clinically. A total of 238 patients with neuroblastoma were classified into four groups according to their age at diagnosis. Patients in group A were 0-5 months of age (n = 31). Patients in group B were detected clinically and were 6-11 months of age (n = 25). Patients in group C were 6-11 months of age and were detected by mass-screening (n = 97). Patients in group D were more than 12 months of age (n = 85). The age-related heterogeneity was evaluated by Kaplan-Meier survival analysis, several clinical markers (neuron specific enolase, ferritin, vanillylmandelic acid and homovanillic acid) at diagnosis, tumor Ha-ras p21 expression and tumor N-myc amplification. Infant neuroblastoma had unique features in comparison to neuroblastoma diagnosed over 12 months of age. Clinical outcome of the patients in groups A and C was quite favorable. Even patients with stage III or IV disease in group A had a favorable prognosis. However, stage IVs disease in group A was not necessarily associated with a good prognosis and the early death after diagnosis was also characteristic. The biological profile of tumors in group C was similar to that in group A but different from the profile in groups B and D. Tumors in group B had a biological profile intermediate between groups A and D.(ABSTRACT TRUNCATED AT 250 WORDS)