Retinoic acid therapy in “degenerative‐like” neuro‐langerhans cell histiocytosis: A prospective pilot study

Abstract

Background Degenerative‐like neuro‐Langerhans cell histiocytosis (DN‐LCH) is a rare complication of LCH marked by progressive cerebellar ataxia. No treatment has so far been shown to slow this progression. Procedure All‐trans retinoic acid (ATRA) was administered orally at a dose of 45 mg/m² daily for 6 weeks and then 2 weeks every month for 1 year. The endpoints were clinical status at 1 year (assessed with rating scales for ataxia and disability), adverse effects, and changes in neurological abnormalities on MRI. Results Ten patients were studied. The treatment was well tolerated. All the patients were clinically stable at the end of the study. No MRI changes were noted. Conclusions DN‐LCH appeared to be stable during ATRA therapy, but further studies are required to appreciate the possible long‐term benefits of ATRA.