Eruptive squamous cell carcinomas with keratoacanthoma-like features in a patient treated with ruxolitinib.

Abstract

Funding sources: none. Conflicts of interest: none declared. Dear Editor, Ruxolitinib is a Janus kinase (JAK)1 and JAK2 inhibitor, approved by the US Food and Drug Administration (FDA) in November 2011. It is highly effective in the clinical management of myelofibrosis and associated complications (splenomegaly consequent to extramedullary haematopoiesis, cytopenias). We describe a case of ruxolitinib‐induced eruptive squamous cell carcinomas with keratoacanthoma‐like features in a patient with myelofibrosis. A 74‐year‐old woman was diagnosed with myelofibrosis in 2013 and was put on ruxolitinib, without association with other immunosuppressive drugs. Her family and personal history were negative for skin tumours and autoimmune diseases. The patient appeared as Fitzpatrick skin type III with moderate bilateral photodamage of the forearms, face, neck and lower legs. After 2 months of ruxolitinib treatment, multiple, simultaneous crateriform nodules appeared on her forehead (Fig. 1), lower jaw and clavicle (Fig. 2), and eruptive squamous cell carcinomas with keratoacanthoma‐like features were suspected. Surgical excision under local anaesthesia was performed, and histopathological examination confirmed the clinical diagnosis and negative involvement of the margin. Because of the suspected association between recently introduced myelofibrosis treatment and skin lesions, administration of ruxolitinib was discontinued. After 10 months of clinical follow‐up, additional skin lesions did not appear.