Endocrine Abstracts

Introduction: Hashimoto’s thyroiditis (HT) is a well known risk factor for thyroid lymphoma. A rapidly enlarging goiter accompanied by lymph nodes pressure on surrounding structures usually suggest the development of thyroid lymphoma.

Case report: An 85 years old hypertensive women presented for a massive goiter extending from the lower jaw to clavicle which increased in size for the last 5 months. She also complained of dysphagia, hoarseness and shortness of breath. Two previous computed tomographies (CT) showed a huge diffuse goiter progressively narrowing the cervical trachea and cervical and mediastinal grossly enlarged lymph nodes. A suspicious cervical lymph node was removed and the pathology report suggested a small B-cell non-Hodgkin lymphoma. However, the immunohistochemistry was in favour of a nonspecific lymphadenitis. In our clinic the cervical CT confirmed the massive diffuse goiter, at least 32 by 53 by 89 mm per lobe. The goiter was intensely hypoechoic on ultrasound suggesting HT or thyroid lymphoma. Thyroperoxidase and thyroglobulin antibodies were strongly positive (over 1000 UI/ml and 3000 UI/ml respectively) but the thyroid function was almost normal (thyroid stimulating hormone was 4.9 mU/l). Serum calcitonin was 2.2 pg/ml. An open thyroid biopsy was performed and the pathology indicated HT. No treatment was started and after 2 months the goiter was still increasing in size but with widening of the trachea and relieve of symptoms. The autoimmunity was similar and the thyroid function continued to be normal.

Conclusions: Hypertrophic HT can clinically and imagistically mimic thyroid lymphoma. An open biopsy of the thyroid may be required in these cases.