Non-Hodgkin's thyroid lymphoma associated with Hashimoto's thyroiditis.

We report two cases of thyroid lymphoma. First was of a 54-year-old lady who presented with a 10 year history of goiter. Examination revealed an enlarged thyroid gland extending sub-sternally, with no palpable lymph nodes. She had been on thyroxine for 4 months, due to a high TSH with positive antibodies. Fine needle aspiration cytology of thyroid showed Hashimoto thyroiditis (HT). A total thyroidectomy was done because of pressure symptoms. Histopathology revealed HT in right lobe and Diffuse Large B-cell Non-Hodgkin's lymphoma (DLBCL) in left lobe. Second case was of a 30 year-old man who presented with dyspnoea secondary to rapidly enlarging thyroid. On examination, thyroid was diffusely enlarged together with palpable lymph nodes. His TSH was elevated & Anti-TPO antibodies were positive suggesting an autoimmune etiology. Ultrasound showed, an ill-defined heterogeneous mass in the left lobe of thyroid gland with multiple enlarged lymph nodes. Ultrasound guided thyroid core biopsy revealed DLBCL.