Tumor Boards

NTRK3 Fusion

Virtual Molecular Tumor Board


Atrium Health
Levine Cancer Institute
Presented by: Michael Livingston, MD, and Megan Jagosky, MD
Patient: NTRK3 Fusion positive recurrent malignant peripheral nerve sheath tumor with neurofibromas

Initial Diagnosis

A 34-year-old female with history of Neurofibromatosis type 1 (NF1) and malignant peripheral nerve sheath tumor (MPNST) of the left pelvis sought medical attention in April 2019 due to progressive left lower extremity swelling over several months. Her oncologic history began 10 years prior when she was originally diagnosed with MPNST of the left pelvis and underwent resection with adjuvant adriamycin, ifosfamide, and radiation. Diagnostic imaging for the new left lower extremity swelling demonstrated a large hypermetabolic left-sided pelvic mass, measuring 10 cm in greatest dimension with a max SUV of 11.7. A biopsy of that mass demonstrated patchy S-100 positive cells with negativity for CD34, and cytokeratin AE1/AE3 confirming recurrent MPNST in the left hemipelvis region.

April 2019 PET/CT:

  • Left pelvic mass (10cm length, max SUV 11.7) extending from L4 deep into pelvis
  • Low SUV mass left neck (4 cm, SUV 3.8)
  • Small hypermetabolic focus right thyroid gland (max SUV 4.0)
  • Multiple subcutaneous neurofibromas

April 2019 MRI:

  • Stable mass effect of the left neck compared to 2015 scan
  • Marked interval enlargement previous identified right S1 neurofibroma at L5 (3.1X1.7X1.9cm)
  • Compression caudal roots and enlargement ventral CSF
  • Enlargement mass left L4-L5 region (8.9cm)