Objectives: Nodular or pseudo-nodular aspects of Hashimoto's thyroiditis raise the problem of the association with a differentiated carcinoma or a non Hodgkin's lymphoma.
Methods: We looked for patients needing surgery in 165 cases of Hashimoto's thyroiditis. For this purpose, we used fine needle aspiration cytology.
Results: We found a differentiated carcinoma in 4% of cases and a non Hodgkin's lymphoma in 1% of cases.
Conclusion: In nodular or pseudo-nodular aspects of Hashimoto's thyroiditis, fine needle aspiration cytology is helpful for the nodule diagnosis and for the selection of suspicious nodules only to be referred to surgery.