Erdheim-Chester Disease of the Jaws: A Case Report and Review of the Literature.

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytic disease characterized by xanthogranulomatous infiltration of multiple organ systems by histiocytes that are negative for langerin (CD207) and CD1a. BRAF V600E mutation is present in 54% of the cases. The disease most commonly affects males in their 5th and 7th decades and bone is involved in 96% of cases although there have been only 8 reported cases of ECD involving the jaws. This is a case of ECD in a 57-year-old male who presented for extractions and implant placement. Radiographic examination revealed extensive bone loss in the posterior mandible and maxilla. Biopsy of the lytic lesions showed infiltration by epithelioid histiocytes with Touton-type multinucleated giant cells that were positive for BRAF and CD163 and negative for CD1a, consistent with the patient’s known history of ECD. He had been diagnosed with ECD 8 years prior with involvement of the long bones and subsequently the skin. The patient started vemurafenib treatment in July 2020 for progressive disease and his disease remains stable. Of the 8 previously reported cases involving the jaws, the median age at diagnosis was 35 years and both genders were equally affected. Reports describe multiple, often bilateral, mixed lytic-sclerotic lesions. Both the mandible and maxilla were affected in 75% of the cases and the mandible alone was involved in one case. None of the cases affected the maxilla alone. Current management includes the use of BRAF inhibitors and MEK inhibitors in the presence of BRAF mutations.