Giant infantile plexiform cellular schwannoma of the knee

Abstract

We describe an infant with a painless but rapidly enlarging plexiform cellular schwannoma over the anterior aspect of the knee. It is a diagnostic challenge for the histopathologist to differentiate between plexiform schwannoma and a malignant peripheral nerve sheath tumour or plexiform neurofibroma which has an association with neurofibromatosis type 1 and carries a risk of sarcomatous change. This benign peripheral nerve sheath tumour is characterised by a multinodular and plexiform growth pattern. To date no report has been published in the European literature describing a rapidly growing giant plexiform cellular schwannoma in an infant. This diagnostic dilemma and rarity of this condition are the unique features of this case report.