Pityriasis rotunda as an incidental paraneoplastic finding in two patients with multiple myeloma

Summary Pityriasis rotunda (PR) is an uncommon chronic dermatosis, which may be idiopathic or may be associated with infections or malignancy. We describe the clinical and biochemical findings of two patients with multiple myeloma, who were incidentally diagnosed with PR, and detail the clinical conditions with which this rare paraneoplastic phenomenon may be associated. Although PR is a rare condition, it may be found as a paraneoplastic phenomenon in a range of conditions, and thus should be recognised as an important clinical sign.