DLBCL : Thyroid

Comments:
Diffuse Large B-cell Lymphoma of Thyroid: Primary lymphomas of the thyroid account for 1% to 5% of all thyroid malignancies and comprise 1% to 2.5% of all lymphomas. They are usually seen in older individuals (median age 60-70 years) with a female predominance.

In most patients, thyroid lymphomas arise in a background of Hashimoto thyroiditis (which causes 40-80 fold increased risk for thyroid lymphomas as compared to individuals without Hashimoto thyroiditis). Patients usually present with a rapidly enlarging neck mass which may be accompanied by cough, dyspnea, hoarseness, and dysphagia.

Macroscopically, thyroid lymphomas may be multinodular (as shown in this image) or produce diffuse enlargement of a lobe or entire gland. They may be soft or firm with smooth pink-tan or greyish-white appearance. Morphologically, the most common subtype of thyroid lymphoma is diffuse large B-cell lymphoma (DLBCL) accounting for 60-90% of cases. The second most common subtype is MALT lymphoma (10-30% of cases). Many of the DLBCL cases arise by transformation of underlying MALT lymphoma. Less than 10% of cases consist of follicular lymphomas, Burkitt lymphoma, and peripheral T-cell lymphoma.