A Case of Diffuse Large B-cell Lymphoma Transformed from Primary Thyroid MALT Lymphoma

Diffuse large B cell lymphoma (DLBCL) is main subtype of primary thyroid lymphoma and can be histologically transformed from a low-grade B-cell lymphoma. The characteristics and treatment guidelines of these particular DLBCL have not been fully established. The mainstay of treatment of primary thyroid DLBCL is multimodality treatment with chemotherapy and radiotherapy. Meanwhile, surgery can be considered only for diagnosis or alleviation of airway compressive symptoms.A 57-year-old female visited our outpatient clinic for recently enlarged long-held anterior neck mass. A thyroid mass compressing the airway and esophagus was identified on imaging, which was diagnosed as MALT lymphoma by excisional biopsy. After staging, the patient underwent total thyroidectomy with regional lymph node dissection for treatment of stage IIE MALT lymphoma and relieving airway compromise symptoms. The final diagnosis was DLBCL transformed from MALT Lymphoma, and chemotherapy was additionally performed. We report this rare experience with a review of literature.