Mechanism and relevance of ploidy in neuroblastoma

Neuroblastoma has a broad spectrum of clinical behavior, ranging from spontaneous regression to dissemination and fatality. The heterogeneity that has long puzzled many investigators has been shown by more recent studies to be closely correlated with various clinical and genetic factors. Tumor cell ploidy is one of the factors; diploid and near-triploid neuroblastomas show poor and excellent clinical outcomes, respectively. We offer a hypothesis that explains how the ploidy state of the tumor plays a fundamental role in this heterogeneity, and why various prognostic factors are correlated with each other. This hypothesis may be applicable to tumors other than neuroblastoma.