Thyroseq Genetic Testing

Around 20-25% of needle biopsies from thyroid nodules are reported in the indeterminate category (Bethesda III / Thy-3a or Bethesda IV / Thy-3f).  This means we don’t know whether they are benign or malignant, and most patients end up requiring surgery for definitive diagnosis. 

Thyroseq genetic testing is a procedure where genetic testing is performed on indeterminate thyroid nodules.  With this technique, around two thirds of indeterminate thyroid nodules can be definitively classified as benign, with the same confidence as a benign biopsy, and thus patients can avoid surgery.  In case of your thyroid nodule having an indeterminate biopsy, we will probably discuss with you the option of Thyroseq genetic testing as an alternative to surgery.

If a recommendation for molecular testing is made in the case of your nodule, it may be possible to do this on the biopsy material which has already been taken, but if this material is not sufficient, a new appointment for a further biopsy may be required. 

Please note that if a repeat biopsy shows benign findings, then the sample will not be sent for molecular testing.  Similarly, in case of thyroid biopsies which have been reported outside CUH, the original slides will be first reviewed by our cytopathologist, and if the results are downgraded to benign based on this review, the sample will not be sent for molecular testing, and the nodule will be considered as benign.

Once the samples are sent for ThyroSeq testing, the results take approximately 4 weeks to come back. These may then require re-discussion at the Thyroid MDM. Therefore you should allow at least 6 weeks from the time the sample was sent for your return appointment to discuss the results.