CD44 Expression in Neuroblastoma and Related Tumors

Purpose: A retrospective study was conducted to investigate the relationship between CD44 expression in neuroblastoma and related tumors and other known prognostic indicators. Materials and Methods: Immunostaining of CD44 was done on surgical specimens of 55 cases (42 patients) of neuroblastoma (NB) and ganglioneuroblastoma (GNB) and nine cases of ganglioneuroma. The percentage of positive tumor cells was scored semiquantitatively (0-4+) by two observers. CD44 expression was then correlated with survival, age, stage, and N-myc amplification. Results: Fifty-seven percent of the patients with NB or GNB had heterogeneous positive staining (2-4+) on their diagnostic specimens. Twenty-four percent of the patients had no staining for CD44, and 19% had 1+ staining. In the 17 cases with N-myc analysis, an inverse relationship was demonstrated between N-myc and CD44 expression by univariate analysis. Lack of expression of CD44 was highly associated with pool survival (p = 0.0002). When assessing the joint effects of age, stage, and CD44 in multivariate 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 or low expression of CD44 correlates with poor survival and may be a biologic marker of tumor aggressiveness. CD44 appears to be an independent prognostic marker and deserves continued investigation in prospective studies of neuroblastoma.