Mediastinal Mass with Hyper-eosinophilia in a Young Boy -A Diagnostic Dilemma.

Mediastinal masses in children comprises of a heterogeneous group of tumours. In such cases, biopsy and histological analysis are mandatory for planning of treatment. We have reported an unusual aetiology for a mediastinal mass in a young boy presenting with features of Superior Vena Caval Obstruction (SVCO) who also had marked blood and marrow eosinophilia mimicking Chronic Eosinophilic Leukaemia (CEL). We have also discussed the differential diagnoses of mediastinal tumours with hyper-eosinophilia and possible therapeutic implications.