[Primary lymphoma of the thyroid gland. Review of the literature and presentation of a clinical case].

Primary malignant lymphoma of the thyroid is a very uncommon disease and represents approximately 5% of all thyroid malignant neoplasms. The Authors report a case whose clinical and histopathological features are discussed and compared with those of previously published series. Primary malignant lymphomas raise a number of issues: abrupt onset, age and sex patterns, histological typing (virtually 100% of cases are non-Hodgkin lymphomas), differential diagnosis with either Hashimoto's chronic thyroiditis (often associated with thyroid primary lymphomas) or genuine anaplastic carcinoma of the thyroid. Routine histological study can be complemented by immunohistochemistry. The treatment of choose is total thyroidectomy plus radiotherapy in cases where radical surgery is possible, or radiotherapy alone which usually carries good results.