Primary malignant peripheral nerve sheath tumor at unusual location

Abstract

Malignant peripheral nerve sheath tumor (MPNST) is a rare soft tissue sarcoma. Most arise in association with major nerve trunks. Their most common anatomical sites are the proximal portions of the upper and lower extremities and the trunk. MPNSTs have rarely been reported in literature to occur in other unusual body parts. We review all such cases reported till now in terms of site of origin, surgical treatment, adjuvant therapy and outcome and shortly describe our experience with two of these cases. Both of our case presented with lump at unusual sites resembling neurofibroma, one at orbitotemporal area and other in the paraspinal region with characteristic feature of neurofibroma with the exception that both had very short history of progression. They underwent gross total removal of the tumor with adjuvant radiotherapy postoperatively. At 6-month follow-up both are doing well with no evidence of recurrence.

Keywords: Malignant peripheral nerve sheath tumor; orbito-temporal; paraspinal; unusual body parts.

Figure 1

(a) Preoperative photograph. (b) showing the orbitotemporal lump with proptosis. (c) Postoperative cosmesis and (d) Excised tumor mass

Figure 2

Magnetic resonance imaging of the orbit and brain showing left sphenoidal-based extra-axial plane (a) and contrast (b) marginated in-homoginously enhancing mass at the lateral side of the left optic nerve buckling the ipsilateral antero temporal lobe

Figure 3

(a) Histopathology picture showing fascicles of spindle cells with marked hypercellularity and high mitotic activity suggestive of MPNS. (b) Immunohistochemistry demonstrates S-100 protein staining of the tumor tissue

Figure 4

Clinical photograph (a) of case-2 showing the left lumbar mass (Yellow arrow) with excised tumor tissue (b)

Figure 5

Magnetic resonance imaging of spine in sagittal view shows a T1 (b) hypo, T2 hyper (a) heterogenously enhancing lumbar (L1- L4) extradural mass lesion with associated L3 vertebral body compression collapse