Thyrotoxicosis secondary to involvement of the thyroid with malignant lymphoma

A patient with malignant lymphoma developed goiter and thyrotoxicosis during the course of her disease. A thyroid biopsy revealed involvement of the thyroid gland with a malignant lymphoma. This was associated with the high levels of circulating thyroglobulin and thyroid hormones. The patient was treated with propylthiouracil, local radiotherapy, and nitrogen mustard and prednisone. The patient became euthyroid with the disappearance of goiter. Circulating levels of thyroglobulin and thyroid hormones returned to the normal range.