These include neuron-specific enolase (NSE) and GD2, which are present in NB and sometimes in osteosarcomas and rhabdomyosarcomas;2,3 CD99 expressed by Ewing's sarcoma and by some PNETs;4,5 NB84 expressed by NB cells and sporadically by Ewing's and PNETs;6 and desmin and cytokeratin present in desmoplastic tumours.7 However, none of these markers has, by itself, clinical utility in unambiguously differentiating small round blue cell tumours.8 Here, ENO2 is linked to neoplasm.