Targeted therapy with BRAF inhibitor Vemurafenib in relapse/refractory multisystem langerhans cell-retrospective analysis from a tertiary care center in India

Abstract

IntroductionBRAF V600 E mutation is present in 50% cases of LCH and is associated with aggressive forms of disease-particularly liver dysfunction in infants and younger children. It is associated with increased mortality due to poorer response to chemotherapy and higher rate of relapse. Though targeted therapy with Vemurafenib shows rapid clinical response and prevents end organ related mortality, optimal duration of therapy and combination of chemotherapy needs further studies. Material & methodsWe discuss here follow up of 3 patients with Relapse/Refractory LCH and BRAF mutation who were salvaged with Vemurafinib. ResultsThree patients with Relapse/Refractory MS LCH were treated in our centre with Vemurafenib. All 3 patients showed dramatic response to Vemurafenib at initiation as well as subsequent relapse on stopping. On PET scan, 2 patients had CR at 6 weeks and 3rd patient had PR on 6 and 12th week. We then used slow taper of vemurafenib with/without addition of oral chemotherapeutic agents and continued a minimal dose successfully in all the 3 patients to prevent recurrences. ConclusionVemurafenib is a safe and effective salvage option to be used early in refractory/relapsed disease to prevent end organ damage. Gradual taper and maintaining a minimal dose with/without addition of oral chemotherapeutic agents may help in preventing recurrences.