Case report: Successful treatment of advanced urothelial carcinoma with trophoblastic differentiation using Tislelizumab and Disitamab vedotin.

BACKGROUND

Urothelial carcinoma with trophoblastic differentiation represents an uncommon and aggressive malignancy for which there is currently no established standard treatment. Systemic chemotherapy as the main treatment has limited efficacy. However, recent research has demonstrated significant improvements in patient survival with the use of immune checkpoint inhibitors and antibody-drug conjugates. To our knowledge, this case represents the first successful application of an immune checkpoint inhibitor (Tislelizumab) combined with human epidermal growth factor receptor 2-targeting antibody-drug conjugate (Disitamab vedotin) in the treatment of advanced urothelial carcinoma with trophoblastic differentiation.

CASE REPORT

We describe the case of a 36-year-old male patient diagnosed with urothelial carcinoma with trophoblastic differentiation, showing high expression of programmed death-ligand 1. Tumor progression occurred after six cycles of Tislelizumab combined with chemotherapy (gemcitabine and cisplatin) followed by five cycles of Tislelizumab monotherapy. Re-biopsy confirmed metastatic urothelial carcinoma with trophoblastic differentiation, now with epidermal growth factor receptor 2 overexpression. Treatment with Disitamab vedotin in combination with Tislelizumab resulted in a biochemical and imaging complete response, leading to an overall survival exceeding 24 months. Notably, no grade 3 or 4 adverse events were observed during treatment.

DISCUSSION

The prognosis of advanced urothelial carcinoma with trophoblastic differentiation is unfavorable, and the available therapeutic options are limited. Combining Tislelizumab with Disitamab vedotin presents a promising anti-tumor strategy that warrants further investigation.