LAUSR

BACKGROUND Invasive urothelial carcinoma (UC) with squamous and glandular differentiation is a highly malignant and complicated pathological subtype, and the standard care is radical cystectomy (RC). However, urinary diversion after RC significantly reduces patient quality of life, thus bladder-sparing therapy has become a research hotspot in this field. Recently, five immune checkpoint inhibitors have been approved for systemic therapy of locally advanced or metastatic bladder cancer by the Food and Drug Administration, but the efficacy of immunotherapy combined with chemotherapy for invasive UC is still unknown, especially for pathological subtypes with squamous and glandular differentiation. CASE SUMMARY We report the case of a 60-year-old male who complained of repetitive painless gross hematuria and was diagnosed with muscle-invasive bladder cancer with squamous and glandular differentiation, defined as cT3N1M0 according to the American Joint Committee on Cancer, who had a strong desire to preserve the bladder. Immunohistochemical staining revealed that programmed cell death-ligand 1 (PD-L1) expression in the tumor was positive. Thus, a transurethral resection to maximize removal of the bladder tumor was performed under cystoscopy, and the patient subsequently received a combination of chemotherapy (cisplatin/gemcitabine) and immunotherapy (tislelizumab) treatment. No tumor recurrence in the bladder was observed following pathological and imaging examination after 2 cycles and 4 cycles of treatment, respectively. The patient achieved bladder preservation and has been tumor-free for more than two years. CONCLUSION This case shows that the combination of chemotherapy and immunotherapy might be an effective and safe treatment strategy for PD-L1 expression positive UC with divergent histologic differentiation.