Table 2 FNAC Diagnostic categories and recommended actions

Thy 1

Non-diagnostic, insufficient sample.

Cyst containing colloid or histiocytes only, in the absence of epithelial cells.

To repeat FNAC. Ultrasound-guidance may help.

If cyst aspirated to dryness with no residual swelling, clinical/ultrasound follow-up alone may be sufficient.

Thy 2

Benign, non-neoplastic.

Cyst containing benign epithelial cells.

Repeat FNAC in 3 - 6 month. Two non-neoplastic results 3 - 6 months apart should exclude neoplasia.

Thy 3

Follicular or Hurthle cell lesion/suspected follicular or Hurthle neoplasm.

(Figure 1)

MDT discussion - diagnostic lobectomy.

Thy 4

Suspicious of malignancy.

(Figure 2)

MDT discussion - surgical intervention, e.g. Total thyroidectomy.

Thy 5

Diagnostic of malignancy.

MDT discussion - surgical intervention, e.g. Total thyroidectomy.