Abstract
Congenital ichthyosis is an uncommon spectrum of hereditary and sporadic hyperkeratotic epidermolytic disorders that may occur in isolation or in association with other clinical syndromes. The pattern of distribution of the hyperkeratotic lesions and family history form the basis of diagnosis. Ichthyosis may be a marker for immune deficiency and cancer prone conditions. We report a 16-year old Chinese patient with a diagnosis of ichthyosis hystrix hystrix (disseminated congenital naevus) since birth who presented with T cell acute lymphoblastic leukaemia with tetraploid clones. There are four reports of acute leukaemia complicating ichthyosis, all involving paediatric acute lymphoblastic leukaemia. The possible mechanisms involved are discussed.