Ewings Sarcoma-Primitive Neuroectodermal Tumour-Rare Extraosseous Presentation

Arcot Rekha,Anukiran Ravichandran,Rufus Ranjitsingh Edwin,Prabhu Purushothaman

doi:10.4236/crcm.2016.53017

Abstract

Introduction: Ewings sarcoma is uncommon in extra osseous locations. They belong to Ewings family of tumours and the primitive neuroectodermal tumour is often diagnosed based on immuno histochemistry and molecular genetic studies. Discussion: A 50-year-old gentleman presented with complaints of a swelling in the right thigh. With a diagnosis of soft tissue sarcoma, the patient underwent a wide local excision of the tumour. We review literature of the small round blue cell tumour. Conclusion: Extraosseous Ewings sarcoma presenting as a thigh swelling is uncommon. The sarcoma was vimentin positive and CD99 membrane positivity.

Highlights

Ewings sarcoma is uncommon in extra osseous locations
The term primitive neuroectodermal tumour (PNET) first described by Hart and Earle denotes small round cell tumours with varying degrees of neural, glial and ependymal differentiation [7] [8]
PNET are positive for CD 99(a 32 KDa cell surface glycoprotein coded by MIC 2 gene).This is seen in lymphoblastic lymphoma

Summary

Case Report

A 50-year-old gentleman presented with complaints of a swelling in the upper thigh of six months duration. Examination revealed a 9 × 9 cms smooth well defined swelling, occupying the anterior and medial aspect of the right upper thigh (Figure 1). MRI report showed T2W hyperintense mass visualized in medial compartment of the right upper thigh, within the superficial part of adductor longus muscle. With a working diagnosis of a soft tissue sarcoma, the patients underwent a Tru cut biopsy of the lesion which showed a neoplasm composed of cells arranged in sheaths. The patient underwent a wide local excision of the tumour where it was found to be involving the anterior and the medial compartment, adherent to the adductor longus, brevis and partly to the adductor magnus. The lesion was found abutting the femoral sheath .Wide local excision of the tumour was done preserving the femoral vein (Figure 3). The tumour was vimentin positive, CD45 negative SMA negative and CD99 showing membrane positivity in tumour cells (Figure 4)

Discussion

Recent Advances

Conclusion