Dopaminergic neuroblastoma as a poor prognostic subgroup.

Clinical and biological significance of increased urinary excretion of dopamine in Japanese children with neuroblastoma was investigated. There was an increase in dopamine excretion in 19 of 29 patients (66%) and 15 of 19 in stages III and IV (79%). When the ratio of noradrenaline and dopamine was divided into two at the value of 3.5 x 10(-2), the disease-free survival rate was four of 16 (25%) in the low ratio group and nine of 19 (69%) in the high ratio group. In five patients, the urinary analysis revealed that only the level of dopamine was elevated before initiation of the therapy. The common features of these patients were as follows: (1) the age at diagnosis was 1 to 4 years; (2) all originated from the suprarenal region; (3) stages were advanced III or IV; and (4) the prognosis was poor. N-myc oncogene of the primary tumor was evident in three, and all were amplified to 32, 37, and 112 copies. These observations suggested that the immaturity of catecholamine metabolism may correlate to the poor prognosis and that "dopaminergic neuroblastoma" may be a clinical subentity of poor prognostic neuroblastoma.