Abstract
Flow cytometric DNA content analyses were performed on samples of 72 patients with neuroblastoma. Nuclear suspensions obtained from paraffin-embedded samples were prepared using the method described by Schutte et al. DNA ploidy could be determined in 62 out of 72 patients. DNA diploidy was detected in 25 (40.3%) and DNA aneuploidy was in 37 (59.7%) of the 62 patients. High incidence of DNA aneuploidy was observed in patients with prognostically favorable indicators such as age (under one year old), clinical stage (I, II, IVS) and primary site (extraadrenal sites). DNA aneuploidy was associated with age (p<0.0l), clinical stage (p<0.0l) and survival rate (p<0.01). It is of great interest that the distribution of patients differs in clinical stage between DNA diploidy and aneuploidy. Almost all patients with DNA diploidy were observed in advanced clinical stages, whereas patients with DNA aneuploidy were observed in all stages. As our research on samples obtained at different periods from the same patients revealed no changes in DNA ploidy, biological behavior may differ between diploidy and aneuploidy. In patients with diploidy, tumor growth might be too rapid to be diagnosed at an early clinical stage. In contrast, in patients with aneuploidy, tumor growth might be slow. It is concluded that DNA ploidy is not only a significant prognostic factor but also an indicator of biological behavior of neuroblastoma.
