Trisomy 17 in congenital plexiform (multinodular) cellular schwannoma.

Plexiform (multinodular) cellular schwannomas are rare tumors, not associated with neurofibromatosis type 1, that occur more often in children and can be congenital. Their biology is benign and is characterized by the tendency to recur locally without being metastatic. Cytogenetic studies in adult cases of schwannoma indicate a complete or partial loss of chromosome 22 as the most common abnormality. Only two cytogenetic studies describe cases in children, one of which concerned a congenital cellular plexiform schwannoma. Here, we report the cytogenetic analysis of a second case in an 8-month-old boy with recurrence of trisomy 17.