Targeted Therapy with Vemurafenib in Brazilian Children with Refractory
Langerhans Cell Histiocytosis: Two Case Reports and a Comprehensive
Review
Abstract
Langerhans cell histiocytosis (LCH) is characterized by inflammatory
lesions featuring clonal infiltration. The BRAF mutation stands out as
the most prevalent. Vemurafenib has emerged as a therapeutic option. The
off-label use of VMF persists in Brazil. We will delineate the cases of
two Brazilian children suffering from LCH with a positive response to
VMF. Case Report I: The patient underwent standard therapy, but bone
marrow infiltration persisted. After confirming a BRAF V600E mutation
through testing, VMF was initiated, resulting in significant
improvements. Case Report II: The patient initiated VMF and showed a
positive response. After several months, maintenance therapy was
introduced. However, skin lesions recurred upon discontinuation of VMF.
She has been on VMF for a total of 31 months, maintaining remission. The
cases presented represent the first reported instances of off-label VMF
use in Brazil for the treatment of LCH, and both patients have
demonstrated excellent responses to the medication.