[A clinicopathologic study of primary malignant lymphoma of the thyroid with a report of six cases].

From 1977 to 1984, 500 patients with thyroid disease (426 females and 74 males) were seen at the Kure Kyosai Hospital. Among them 6 patients (1 female and 5 males; all older than 50 y) were found to have a primary malignant lymphoma of the thyroid. Histologically, two were identified as being SNC, two were D-Mx, one was a D-L, and the last an IBL (plasmacytoid), according to the Working Formulation. Three patients manifesting a high grade malignancy died within 6 months after the diagnosis. Thyroid autoantibodies were detected in four patients, and, histologically, three of the four had chronic thyroiditis. The relationship between primary malignant lymphoma of the thyroid and chronic thyroiditis is discussed.