CD44 EXPRESSION IN NEUROBLASTOMA AND RELATED TUMORS

Purpose: A retrospective study was conducted to investigate the relati onship between CD44 expression in neuroblastoma and related tumors and other known prognostic indicators. Materials and Methods: Immunostain ing of CD44 was done on surgical specimens of 55 cases (42 patients) o f neuroblastoma (NB) and ganglioneuroblastoma (GNB) and nine cases of ganglioneuroma. The percentage of positive tumor cells was scored semi quantitatively (0-4+) by two observers. CD44 expression was then corre lated with survival, age, stage, and N-myc amplification. Results: Fif ty-seven percent of the patients with NE or GNB had heterogeneous posi tive staining (2-1+) on their diagnostic specimens. Twenty-four percen t of the patients had no staining for CD44, and 19% had 1+ staining. I n the 17 cases with N-myc analysis, an inverse relationship was demons trated between N-myc and CD44 expression by univariate analysis. Lack of expression of CD44 was highly associated with poor survival (p = 0. 0002). When assessing the joint effects of age, stage, and CD44 in mul tivariate analysis, the effect of CD44 remains significant (p = 0.028) and appears to be independent of age and stage. Conclusion: Our data suggest a relationship between CD44 and N-myc amplification. Absence o r low expression of CD44 correlates with poor survival and may be a bi ologic marker of tumor aggressiveness. CD44 appears to be an independe nt prognostic marker and deserves continued investigation in prospecti ve studies of neuroblastoma.