Pityriasis rotunda is:
Pityriasis rotunda - Pityriasis rotunda is described as a persistent, large, sharply defined circular patch of dry ichthyosiform scaling with no inflammatory changes. Variant of Ichthyosis Fixed, annular, scaling, dry-skin change More often seen in the African and Asian races Associated with neoplasia, paicularly Hepatocellular carcinoma.
Fungal infection
Bacterial infection
Pityriasis affecting nail
Variant of Ichthyosis
Tumours of skin