Neuroblastoma is a malignant tumor of neural crest cells, the cells that give rise to the sympathetic nervous system, which is observed in children.

A myxoma (tumor of primitive connective tissue) of the heart. Cardiac myxomas consist of stellate to plump, cytologically bland mesenchymal cells set in a myxoid stroma. Cardiac myxomas are of endocardial origina and general project from the endocardium into a cardiac chamber.