Abstract YO22
Case summary
In the Guardant health database, prevalence of FGFR3-TACC3 is 0.3% in HCC & cholangiocarcinoma, 2.6% in urothelial cancers. We report three cases of advanced tumors with FGFR3-TACC3 fusions detected by CGP in a single center in routine practice. Fusion was detected by ctDNA NGS (Guardant 360, Guardant Health) in two cases and by tissue NGS (ACTOnco, ACT Genomics, Taiwan) in one.
Case 1
A 64-year-old man with urothelial carcinoma in the right renal pelvis, stage cT3N2M1, presented with multiple bone, liver, lung, and lymph node metastases.
Received 3 cycles of pembrolizumab and enfortumab vedotin. A follow-up CT scan showed disease progression in the chest and pelvis. Palliative radiotherapy to cervical spine metastases was administered.
Due to lack of tumor tissue, ctDNA NGS was ordered and reported FGFR3-TACC3 fusion. Treatment with Erdafitinib, gemcitabine and cisplatin resulted in a partial response.
Case 2
A 57-year-old woman presented with intrahepatic cholangiocarcinoma stage cT2N1M1, with metastases to lung, bones, and lymph nodes.
Pembrolizumab with gemcitabine and cisplatin was administered for 4 cycles, but the disease progressed with liver metastasis.
Due to lack of tissue, ctDNA NGS was ordered which reported FGFR3-TACC3 fusion along with other mutations. She received erdafitinib in combination with gemcitabine and cisplatin for 3 cycles, with disease progression leading to death.
Case 3
A 60-year-old man with HBV-related HCC, presenting with metastatic lesions in the lungs, lymph nodes, and omentum.
Over one year he received many lines of treatment, including sorafenib, gemcitabine and cisplatin, , ramucirumab, nivolumab, and liposomal doxorubicin, lenvatinib durvalumab, and ramucirumab. Best response to any regimen was stable disease (SD).
Subsequent tissue NGS revealed FGFR3-TACC3 fusion, leading to enrollment in a FGFR inhibitor clinical trial resulting in stable disease (SD) for 6 months at the time of exiting the trial.
Conclusions: In clinical practice, ctDNA or tumor NGS can detect rare and actionable FGFR3-TACC fusions in patients with advanced solid tumors that have progressed on standard therapy. Targeted therapy for such fusions can result in clinical benefit