Laryngeal Diffuse Large B-Cell Lymphoma Presenting as Laryngeal Stenosis

BACKGROUND: Laryngeal stenosis is challenging for treatment due to uncertain etiology. Primary laryngeal lymphoma as the initial clinical manifestation of laryngeal stenosis has been rarely reported. Primary diffuse large B-cell lymphoma as an underlying etiology has not been reported. CASE REPORT: A 79-year-old male presented with dyspnea, stridor and dysphonia of 6 months' duration. Computed tomography scans and flexible laryngoscopic examination revealed vocal cord mobility with bilaterally limited abduction and a subglottic stenosis up to 50%. The laryngeal mucosa was smooth. Laryngeal biopsy showed atypical lymphoid infiltrates, predominantly large sized B-cells, in the submucosa with crush/cauterized artifacts. The tumor cells were positive for B-lymphocyte antigen CD20, paired-box 5 (PAX5), B-cell lymphoma 2 (BCL2), BCL6 and multiple myeloma oncogene 1 (MUM1). They were negative for CD10, CD30, cyclin D1 (CCND1), SRY-box 11 (SOX11), activin-receptor like kinase 1 (ALK1), CD138 and c-MYC, and negative for kappa/lambda light chain and Epstein-Barr virus-encoded small RNA by in situ hybridization. The pathologic diagnosis was diffuse large B-cell lymphoma. Fluorescent in situ hybridization (FISH) for MYC was negative. Next-generation sequencing using a 175-gene panel was performed and no pathologic mutations were identified. No lymphadenopathy elsewhere was identified. The patient was treated with chemotherapy and was doing well at the 5-month follow-up. CONCLUSION: To the best of our knowledge, this is the first documented case of primary laryngeal diffuse large B-cell lymphoma presenting as increasing laryngeal stenosis. The rarity, diagnosis and treatment of this entity are discussed.