Subcutaneous primitive neuroectodermal tumour in the abdominal wall of a child: long-term survival after local...

Tumours of the peripheral primitive neuroectodermal tumour/Ewing's sarcoma (PNET/ES) family can rarely occur as primary lesions within the skin and subcutis. We present a case of subcutaneous PNET within the abdominal wall of a 33-month-old child. Histologically it was a small round cell tumour that marked strongly for CD99 and displayed ultrastructual evidence of neural differentiation. The tumour was completely excised, but due to an initial misdiagnosis no adjuvant therapy was given. Despite this, the patient is well without evidence of disease 10 years and 3 months after surgery. A review of similar cases reveals not all patients are as fortunate, suggesting combination therapy, including chemotherapy, is still the best treatment for these tumours, even when small and superficial. Our report therefore highlights the importance of recognising PNET/ES in the skin and subcutis so appropriate therapy can be administered.