Mediastinal neuroblastoma and ganglioneuroma. The differentiation between primary and secondary involvement on the chest roentgenogram.

The roentgenologic diagnosis and differentiation of mediastinal neurogenic tumors are possible on the chest roentgenogram as a rule. The soft tissue mass may be ill-defined and the tumor "ghost-like" in the case of primary neuroblastoma, but it is usually obvious in ganglioneuroma and metastatic disease. The presence of calcifications differentiates neurogenic tumors from other posterior mediastinal tumors of childhood. They are common in primary and rare in secondary disease. Rib erosions and displacement are striking in neuroblastoma (after a few months of age), more subtle in ganglioneuroma, and absent with secondary involvement. In 3 out of 7 posterior mediastinal neuroblastomas the diagnosis and treatment were delayed, as the adjacent rib changes were not appreciated for some time. "Dumbbell" shaped tumors are usually associated with vertebral changes and myelography is indicated even in the absence of neurologic deficit. Thoracic deformity and disability subsequent to laminectomy, radiation therapy, or both, are present in all survivors.