RETROSPECTIVE STUDY OF PROGNOSTIC VALUE OF DNA-PLOIDY AND PROLIFERATIVE ACTIVITY IN NEUROBLASTOMA

Aim-To assess the prognostic value of age and stage at diagnosis, site of primary tumour, cell ploidy and N-myc copy number in children with neuroblastoma. Methods-Flow cytometry was used to determine the cellu lar DNA content of paraffin wax embedded archival material from 69 cas es of neuroblastoma and was successful in 52. Results-The age, stage, and survival distribution of the sampled cases was not significantly d ifferent from that in a larger population based series. There were sev en diploid (''non-aneuploid'') and 45 aneuploid (including two tetrapl oid and four triploid) tumours. The 10 year survival was significantly better for cases of aneuploid rather than diploid tumours (p < 0.05). An important new finding was that 10 year survival was also significa ntly better for tumours with a low percentage of cells in S phase (p < 0.03). Conclusion-The percentage of cells in S phase, a measure of th e proliferative activity of the tumour, correlated with prognosis in n euroblastoma. This should be measured with other biological features o f the disease, such as N-myc copy number, when prognostic indicators a re being assessed.