Case Study: Genomic Analysis Identifies Medullary Thyroid Carcinoma


Afirma MTC, a genomic classifier, pre-operatively diagnoses medullary thyroid carcinoma (MTC) in a patient with an indeterminate-cytology nodule and otherwise unremarkable history.


Background: MTC is an aggressive form of thyroid cancer, for which the American Thyroid Association’s Guidelines recommend a total thyroidectomy and full central neck and lymph node dissection.1 Yet, about 40% of patients with MTC do not undergo the recommended surgery.2,3

Case Description:

A 78-year-old woman with Hashimoto’s disease was examined for a thyroid nodule. An ultrasound exam revealed a complex, predominantly solid and well-defined thyroid nodule with grade 2 vascularity and microcalcifications.


  • An FNA biopsy was sent for Afirma Thyroid FNA Analysis.
  • The cytopathology results came back as indeterminate, consistent with category III of the Bethesda System, atypia/follicular lesion of undetermined significance (AUS/FLUS), or indeterminate.
  • Afirma genomic analysis was performed on a sample collected during the initial FNA biopsy.  Afirma GEC was suspicious, and Afirma MTC was positive for a genomic signature for medullary thyroid carcinoma.
  • A calcitonin study was dramatically elevated and therefore supportive of medullary thyroid carcinoma.1

Outcome: A total thyroidectomy and a central neck dissection were performed. The histopathology confirmed the diagnosis of MTC.

Afirma MTC is able to pre-operatively identify MTC to inform the choice of surgery. In this case, the need for a second surgery for central neck dissection was avoided. Afirma MTC is run automatically at no extra charge when Afirma GEC is performed, and it can be ordered separately for cytology suspicious and malignant nodules, too.

  1. Wells SA, Asa, SL, Dralle H et al. Thyroid Association Guidelines for the Management of Medullary Thyroid Carcinoma. The American Thyroid Association Guidelines Task Force on Medullary Thyroid Carcinoma. Thyroid 2015.
  2. Esfandiari NH et al. JCEM. 2014; 99(2):448-454.
  3. Panigrahi B et al. Ann Surg Oncol. 2010; 17:1490-1498.