FLOW-CYTOMETRIC DNA ANALYSIS OF NEUROBLASTOMA - THE PROBLEMS OF JAPANESE MASS-SCREENING

The introduction of mass screening (MS) has increased the number of pa tients who have been detected in the early clinical stages as well as the total number of patients who have been detected with neuroblastoma (NB). We investigated the problems of MS by DNA content analysis of N B in 89 patients treated at Niigata University Hospital. Surgical mate rials were available for 73 of the 89 patients. Of the 27 patients who received MS, 16 NBs were detected and 11 were not. The numbers of pat ients in the early clinical stages (I, II) were 7 (15.2%) before the i ntroduction of MS an 10 (37.0%) thereafter (P <0.05). Of the 16 patien ts who were detected through MS, 9 (56.3%) were in the early clinical stages. The numbers of patients with DNA aneuploidy were 24 (52.2%) be fore the introduction of MS and 22 (81.5%) thereafter (P <0.05). All 1 6 patients who were detected through MS showed DNA aneuploidy. So far, DNA-ploidy of neuroblastomas has been stable. It is significant that the ratio of patients with DNA aneuploidy has increased with the intro duction of MS. Considering that the total number of patients has incre ased since the introduction of MS, it would seem conclusive that a per centage of patients with DNA aneuploidy would not have had the opportu nity to be treated had it not been for MS.