Site Editors

Alexander Drilon, MD

Gregory J. Riely, MD, PhD

Advertisement
Advertisement

Next-Generation Sequencing Guides Treatment in Spinal Cord Tumor With NTRK Fusion: Case Report

By: Lauren Harrison, MS
Posted: Friday, February 11, 2022

Next-generation sequencing combined with histopathologic examination allowed for identification of an NTRK1 gene fusion in a newborn female presenting with global hypotonia at birth. The patient was treated with a TRK inhibitor and experienced tumor regression. Peter P. Sun, MD, of the University of California, San Francisco, and his colleagues published the case details in The Lancet.

The infant was delivered at 39 weeks after induction of labor for oligohydramnios and decreased fetal movement. At birth, the infant underwent a contrast-enhanced MRI because of global hypotonia, which identified a T1-enhancing intramedullary lesion extending from the medulla to the upper thoracic spinal cord. Quadriparesis progressed as the cervical spine started showing signs of compression from the expanding tumor. A team of neurosurgeons performed a laminoplasty to decompress the cervical spine, partially debulk the tumor, and obtain a biopsy. Histopathologic assessment confirmed a suspected diagnosis of grade IV congenital spinal cord glioblastoma.

Using next-generation sequencing, the treating physicians identified a gene fusion in NTRK1. The tumor also showed diffuse TRK positivity. The patient was given induction chemotherapy and the TRK inhibitor larotrectinib, at a 50% dose of 50 mg/m2 twice a day for 1 week, which was increased to a full dose of 100 mg/m2 twice a day starting in week 2.

After 2 weeks of larotrectinib therapy, the patient had improvement in quadriparesis, and there was a decrease in the size of the lesion on imaging. Eight weeks into treatment with larotrectinib and after four cycles of carboplatin and etoposide, the tumor was no longer visible on imaging. The patient, who began crawling and progressing toward walking at age 17 months, continues on oral larotrectinib as the sole therapy.

“While we could not entirely rule out a response to chemotherapy alone resulting in the improvement seen in our patient, the prognosis for congenital glioblastomas treated with chemotherapy alone remains very poor,” said the authors.

Disclosure: The study authors reported no conflicts of interest.


By continuing to browse this site you permit us and our partners to place identification cookies on your browser and agree to our use of cookies to identify you for marketing. Read our Privacy Policy to learn more.