Mandibular Paresthesia Caused by Unifocal Eosinophilic Granuloma-Like Proliferation in an Adult: a Case Report

Abstract

Background

Langerhans cell histiocytosis (LCH) is a spectrum of rare histiocytic neoplasms characterized by clonal proliferation of Langerhans cell histiocytes along with eosinophils, lymphocytes, plasma cells, and multinucleated giant cells. Approximately 40-60% of all cases of LCH harbor mutations of BRAF and MAP2K1 genes with the timing of these mutations likely impacting the extent of the disease dissemination. Eosinophilic granuloma (EG) represents the mildest form of this spectrum presenting with solitary or multifocal bone lesions while sparing the visceral organs. Accounting for less than 1% of all osseous neoplasms, EG shows a predilection for the axial skeleton with 75% of the cases involving the mandible. While EG can arise across a broad age range, more than half of the cases are found in patients younger than the age of 15 years.

Case Summary

A 51 year-old female patient with a prior history of breast cancer presented to oral and maxillofacial surgeon with a complaint of left-sided mandibular paresthesia. While not appreciable in plain panoramic radiograph, computed tomography (CT) scan revealed an isolated, ill-defined and small radiolucent lesion in the left mandibular ramus. Surgical curettage and biopsy of the lesion revealed a dense mixed inflammatory infiltrate characterized by numerous eosinophils admixed with lymphocytes, plasma cells, scattered giant cells, and occasional histiocytic cells with reniform nuclei reminiscent of eosinophilic granuloma. Immunohistochemical studies confirmed immunoreactivity of these histiocytic cells with CD-1a, CD-207, and S-100 antibodies. Positron emission tomography (PET) scan and comprehensive physical exam ruled out involvement of the other organ systems. Subsequent post-operative follow-up revealed gradual reduction in the radiographic size and improvement in paresthesia.

Conclusion

This rare case suggests that the true spectrum of variations in LCH has yet to be fully appreciated and highlights the importance of utilization of three-dimensional imaging in diagnostic workup of gnathic pathologic lesions.