Expert: Neha Dahiya MD - 7/1/2009

Question
My question has to deal with the "standards" of an FNA pathology report of a thyroid nodule.  I had an FNA of a 1 cm solitary nodule with blood flow and microcalcification.  It stated cytologically benign cells but with evidence of follicular neoplasm.  My surgeon told me to have that lobe removed because of the terms "follicular neoplasm" and the results they might imply.

After surgery, he was quite unhappy that the results came back Hashimoto's disease.  He indicated that the pathology was not done correctly on the FNA, and if it had, he would never have recommended surgery at all.  My question is this: is it standard to check for the lymphocytes that indicate Hashimoto's on all FNA's of thyroid nodules?  He seemed to imply that it most definitely should have been caught!
Thank you,
Sydney

Answer
Hello Sydney:

I cannot comment on the quality of reporting since I have not seen the slides of your FNA.

In general if the aspirate from thyroid shows follicles (collections of cells in a circle with a cavity in the center) and along with other criteria the diagnosis is follicular neoplasm.

It is not possible to distinguish between a follicular adenoma (benign) and follicular cancer on fine needle aspiration. Capsular invasion is important to document to call a lesion cancer if the cells are otherwise having a benign appearance. So if "follicular neoplasm" is mentioned in the report the thyroid lobe is resected.

Hashimoto's does  have more characteristic features which enables a diagnosis on cytology. However sometimes if the aspirate does not have the requisite cells the diagnosis cannot be made. Cytology helps confirm a diagnosis if cells are present, if they are not it does not rule out a condition.