A 71-Year-Old Woman with NTRK Gene Fusion Thyroid Cancer

September 21, 2020

A key opinion leader reviews the case of a 71-year-old woman with NTRK gene fusion thyroid cancer and considers novel therapies available for the management of her disease.


Case: A 71-Year-Old Woman With Thyroid NTRK Gene Fusion Cancer

Initial Presentation

  • A 71-year-old woman presents with a painless “ball on his neck”
  • PMH: hypercholesterolemia, medically controlled
  • PE: palpable, non-tender solitary left-of-the midline neck mass; otherwise unremarkable


Clinical Workup and Initial Treatment

  • Labs: including TSH, anti-Tg antibodies WNL
  • Ultrasound of the neck revealed a 3.8 cm suspicious mass arising from the left thyroid; 4 suspicious submandibular lymph nodes, largest 2.2 cm in size
  • Ultrasound-guided FNAB of the thyroid mass and the largest lymph node confirmed undifferentiated papillary thyroid carcinoma
  • Chest/abdominal/pelvic CT showed no evidence of distant metastases
  • Patient underwent total thyroidectomy with therapeutic central compartment and left selective neck dissection
    • Pathology: 3.8 cm undifferentiated papillary thyroid cancer arising in left lobe of thyroid, 2 of 7 positive central compartment lymph nodes, largest 1.3 cm, no extra nodal extension
  • StageT2N1M1; ECOG PS 0

Follow-Up and Additional Treatment

  • She was treated with radioactive iodine 150 millicuries
    • Whole body scan showed uptake in neck only consistent with thyroid remnant
    • Added levothyroxine to regimen
  • Follow-up at 2 months TSH 0.2 mU/L; thyroglobulin 26 ng/mL
    • MRI of the brain revealed multiple small lesions
  • Biomarkers testing:NTRK fusion+, RET-, BRAF-, NRAS-,KRAS-
  • Initiated treatment with larotrectinib 100 mg PO BID