Vemurafenib in Langerhans cell histiocytosis: report of a pediatric patient and review of the literature

// Anne Heisig 1 , Jan Sörensen 2 , Stefanie-Yvonne Zimmermann 1 , Stefan Schöning 1 , Dirk Schwabe 1 , Hans-Michael Kvasnicka 3 , Raphaela Schwentner 4 , Caroline Hutter 4 and Thomas Lehrnbecher 1 1 Division of Pediatric Hematology and Oncology, Hospital for Children and Adolescents, Johann Wolfgang Goethe-University, Frankfurt, Germany 2 Division of Stem Cell Transplantation and Immunology, Hospital for Children and Adolescents, Johann Wolfgang Goethe-University, Frankfurt, Germany 3 Institute of Pathology, Johann Wolfgang Goethe-University, Frankfurt, Germany 4 St. Anna Kinderspital, Vienna, Austria Correspondence to: Thomas Lehrnbecher, email: Thomas.Lehrnbecher@kgu.de Keywords: Langerhans cell histiocytosis; LCH; child; vemurafenib; BRAF Received: March 12, 2018     Accepted: April 06, 2018     Published: April 24, 2018 ABSTRACT Selective BRAF inhibitors such as vemurafenib have become a treatment option in patients with Langerhans cell Histiocytosis (LCH). To date, only 14 patients receiving vemurafenib for LCH have been reported. Although vemurafenib can stabilize the clinical condition of these patients, it does not seem to cure the patients, and it is unknown, when and how to stop vemurafenib treatment. We present a girl with severe multisystem LCH who responded only to vemurafenib. After 8 months of treatment, vemurafenib was tapered and replaced by prednisone and vinblastine, a strategy which has not been described to date. Despite chemotherapy, early relapse occurred, but remission was achieved by re-institution of vemurafenib. Further investigation needs to address the optimal duration of vemurafenib therapy in LCH and whether and which chemotherapeutic regimen may prevent disease relapse after cessation of vemurafenib.