DNA-PLOIDY IN NEUROBLASTOMA

Neuroblastoma is perhaps the most heterogenous childhood cancer in ter ms of clinical behavior. Stage of disease, age at diagnosis, levels of urinary catecholamine excretion, N-myc amplification, and DNA ploidy have been found to be significant prognostic factors. The aims of this combined retrospective-prospective study are to verify the prognostic significance of DNA ploidy and to show its correlation with other pro gnostic signs. Thirty six fresh and thirty three paraffin embedded sam ples from patients with histologically confirmed neuroblastoma (41 pri or to receiving any chemotherapy) were available for flow cytometry DN A analysis. Our results showed that the maturation induced during chem otherapy could give rise to aneuploidy therefore we analyzed the assoc iations between the DNA ploidy and other prognostic markers only in pa tients examined before chemotherapy.There were no significant correlat ions between DNA ploidy and urinary catecholamine metabolites levels o r tumor localization. DNA aneuploidy was significantly more frequent i n patients with lower clinical stage, lower age at diagnosis, and with out N-myc gene amplification. Patients with DNA aneuploid neuroblastom as died less frequently than patients with DNA diploid tumors. There w ere no significant associations among the S-phase or proliferation fra ction and other prognostic factors.