New Onset SIADH Masquerading Disease Progression during Treatment of Esthesioneuroblastoma

Esthesioneuroblastoma (ENB) is a slow growing malignant tumour of olfactory neuro-epithelium that is locally aggressive with a tendency to recur years later.Infrequently, it can be associated with paraneoplastic syndrome.Here, we a report a pediatric case of ENB in whom syndrome of inappropriate ADH secretion (SIADH) was detected during ongoing primary treatment which reflected disease progression after initial response to chemotherapy, that was substantiated radiologically.SIADH has been reported in only a few cases of ENB.