Primary Thyroid Lymphoma: A Report of Two Cases

Primary lymphomas of the thyroid are uncommon tumours, representing approximately %5 of the thyroid neoplasms and %2 of extranodal lymphomas (1,2,3). The peak incidence is in the 5th to 7th decades and the male/female ratio is 1/3 (2,4). The most characteristic presentation is that of a rapidly enlarging neck mass often associated with dysphagia (5). The majority of patients are euthyroid and one third of patients have compressive symptoms. However distant metastasis is rare. The mass is usually fixed to surrounding tissues and half the patients have unilateral or bilateral cervical lymph node enlargement (2,5,6). Most thyroid lymphomas are nonhodgkin lymphomas and its differentiation from small cell anaplastic carcinoma of thyroid gland may be difficult with FNA (2,7). Lymphoma is eminently treatable, whereas anaplastic carcinoma has a very poor prognosis. Incidence of lymphocytic thyroiditis (Hashimoto’s thyroiditis) in patients