case_images: PMC9928762_01
case_images: Course of the treatment history with serial images, pathologic findings (IHC and FISH), and cfDNA NGS in this patient with a pelvic sarcoma harboring NTRK fusion and MDM2/CDK4 amplification. cfDNA, cell-free DNA; CN, copy number; FISH, fluorescence in situ hybridization; IHC, immunohistochemistry; NGS, next-generation sequencing.
case_images: po-7-e2200528-g001.jpg
case_images: PMC9928762_01_po-7-e2200528-g001.jpg
case_images: fig1
case_images: The tumor specimen was sent for further analysis for next-generation sequencing (NGS; ACTOnco+, ACT Genomics), which mainly disclosed TPM3::NTRK fusion (Appendix Fig A1), and MDM2/CDK4 gene amplification. The analysis of the cfDNA NGS panel before treatment with larotrectinib revealed both TPM3::NTRK1 fusion and MDM2/CDK4 amplification (Fig 1), reliably reflecting the genetic alterations of the original pelvic tumor tissue. After 8 weeks of larotrectinib, follow-up MRI revealed tumor necrosis and regression in size (L x W x H: 8.4 x 6.4 x 9.4 cm; Fig 1). Larotrectinib was continued after operation, and he remained disease-free for a follow-up of 4 months (Fig 1).