[Molecular targeted therapy for Erdheim-Chester disease].

Area of Science:

• Oncology
• Genetics
• Pharmacology

Background:

• Erdheim-Chester disease (ECD) is a rare non-Langerhans histiocytic disorder.
• Currently, no established therapeutic approach exists for ECD.
• The BRAF V600E mutation is implicated in some ECD cases.

Purpose of the Study:

• To report a case of ECD treated with molecular targeted therapy.
• To evaluate the efficacy and safety of a BRAF inhibitor and MEK inhibitor combination in an ECD patient with BRAF V600E mutation.

Main Methods:

• A 61-year-old female patient with ECD and BRAF V600E mutation received combination therapy with dabrafenib (BRAF inhibitor) and trametinib (MEK inhibitor).
• Treatment involved monitoring for adverse events, including fever and liver injury.
• Response was assessed using plasma BRAF V600E allele frequency and PET/CT scans.

Main Results:

• The patient experienced manageable Grade 1 fever and liver injury, necessitating temporary treatment interruption.
• Treatment was successfully resumed with the addition of prednisolone.
• BRAF V600E allele frequency became undetectable by 8 weeks, and a partial metabolic response was confirmed by PET/CT at 24 weeks.

Conclusions:

• Molecular targeted therapy, specifically BRAF and MEK inhibitors, demonstrates potential benefit for ECD.
• Management of side effects, such as fever and liver injury, is crucial for successful treatment continuation.
• Further research is needed to establish treatment guidelines, efficacy indicators, and cessation criteria for ECD targeted therapy due to its rarity.