Extranodal non-Hodgkin’s lymphoma presented as bilateral enlargement of the mandibular canals: a case report

Introduction

Bilateral enlargement of the mandibular canals (BEMC) is extremely rare and the differential diagnosis includes vascular malformation, benign neural tumors, or localized hypertrophic neuropathy. Extranodal non-Hodgkin’s lymphoma (ENHL) involving the mandibular canals is exceptionally rare with only five cases reported. Herein, we report an interesting case of ENHL presented as BEMCs.

Materials and Methods

A 43-year-old Saudi woman came to our oral surgery clinic complaining of heaviness in her mandible for 9 months. The panoramic radiograph revealed a bilateral diffuse uniform thickening of the mandibular canal. MRI showed isolated bilateral thickening and enhancement of mandibular branches of the trigeminal nerves with no involvement to the adjacent structures.

Results

An incisional biopsy was performed and microscopic examination showed a diffuse lymphocytic infiltration admixed with few plasma cells in a background of fibrosis. Neoplastic cells were positive for CD20 and PAX5 with Kappa chain restriction. Cyclin D1, IgG4, BCL6, and CD10 were negative. IgH rearrangement was positive for the clonal-B-cell receptor (IGH) gene.

Conclusions

We present an extremely unusual case of ENHL expanding the radiographic differential diagnosis of BEMC. More importantly, this was the first sign of primary ENHL. Thus, BEMC should rise the possibility of early malignancy which will allow early diagnosis and intervention.