Endocrine Abstracts

Introduction: Many thyroid conditions are associated with the development of a rapidly progressing goiter and should evoke several diagnoses, some of which may be of poor prognosis.

Case-presentation: A 47-year-old female patient with no previous pathological history presented with a large goiter associated with a deteriorated general condition that had been evolving for 3 weeks On examination, she presented with a fever at 39°C, multiple cervical adenopathies of hard and painful consistency, pallor, gingival enlargement, and a painless large goiter of hard consistency, associated with compressive signs: dysphagia and dysphonia. Her biological tests showed: hyperleukocytosis at 77390/mm³ with 49% blasts, anemia at 7.3 g/dl, and thrombocytopenia at 33000/mm³. TSH was elevated to 65 mIU/l, FT4 was low at 7.02 pmol/l, LDH was high at 560 IU/ml. Anti-thyroperoxidase and anti-thyroglobulin antibodies were positive at 468 and 566 mIU/ml respectively. The bone marrow aspiration revealed a marrow infiltrated by 59% blasts in favor of acute myeloblastic leukemia type 5 (AML). The karyotype was without abnormality. Immunophenotyping was in favor of Aml. A cervical ultrasound revealed an enlarged thyroid with heterogeneous pseudonodular hypoechoic echostructure associated with multiple cervical adenopathies. Fine needle aspirates (FNA) from the thyroid revealed the presence of benign epithelial cells in both lobes without signs of malignancy. The patient was put on Levothyroxine replacement therapy and treated with Cytarabine and anthracycline chemotherapy. The evolution was marked by a complete remission of her AML and an incomplete regression of her goiter with an improvement of compressive signs.

Discussion: The rapid development of a large goiter in the context of an deteriorated general condition should first evoke: anaplastic cancer, primary thyroid lymphoma, Riedel’s Thyroiditis or a secondary thyroid tumor localization. FNA is the key examination in this situation. Our case illustrates the association of AML and Hashimoto’s Thyroiditis revealed by a large goiter of rapid evolution. Hashimoto’s thyroiditis is associated with a higher risk of developing certain cancers, including leukemia. Various hypotheses have been put forward regarding the underlying pathophysiological mechanisms, including chronic inflammation and its role in oncogenesis. Further studies will be necessary to better elucidate the mechanisms involved.