Malignant peripheral nerve-sheath tumor arising in a previously irradiated neuroblastoma: report of 2 cases and a review of the literature.

BACKGROUND: Only ten cases of the rare occurrence of a malignant peripheral nerve-sheath tumor (MPNST) arising in a ganglioneuroma either de novo or at a site of previous irradiation have been reported. PATIENTS AND METHODS: We present two children who at the age of 19 months and 6 months were diagnosed with a cervicothoracic ganglioneuroblastoma and a retroperitoneal neuroblastoma, respectively. They both received radiation therapy as part of the treatment of their disease. RESULTS: Following a 12-year interval, MPNST arose inside a benign ganglioneuroma in both patients. We illustrate the imaging findings in these two cases and review the cases reported in the literature to increase awareness of this association among radiologists.