Large foot schwannoma with bone invasion - a case report

A rare case of a large foot schwannoma with an intraosseous component is presented. Due to suspicion of malignancy, an amputation had previously been proposed. When the patient presented to us, the prolonged clinical course as well as some elements of the imaging exams suggested benignancy and we decided for complete tumor excision. Intraoperative findings supported the benign character of the neoplasm and pathology would later confirm the diagnosis of a benign schwannoma. The outcome, at 18 months of follow-up was a fully functional limb. Recurrence must still be considered but malignant transformation is very rare in a solitary schwannoma and can be discounted. Solitary benign schwannomas have a negligible malignization potential independently of their size or osseous component. When benignancy is considered, primary total tumor excision, as part of a staged procedure, is a safe approach. It allows for a thorough pathologic examination and eventually for a definitive treatment.