Chemotherapy combined with immunotherapy in primary female urethral squamous cell carcinoma: a case report.

Primary female urethral carcinomas are uncommon and have a low morbidity rate. Most of these patients have advanced illness with high invasion and a poor prognosis. There is no standard treatment, and multimodal therapy is recommended. The use of radiotherapy and chemotherapy were mostly reported in previous studies on advanced female urethral squamous cell carcinoma. We report that chemotherapy combined with a programmed death-1 (PD-1) inhibitor was effective in treating metastatic female urethral squamous cell carcinoma. During four cycles, we used systemic chemotherapy of albumin-paclitaxel + carboplatin in combination with a PD-1 inhibitor (toripalimab 240 mg) every 3 weeks, and a complete response was achieved. We performed a genetic test on the patient who had a tumor mutation burden of 5.7 mutations/Mb, tumor proportion score of 20%, and combined positive score of 20% (22C3). No recurrence or distant metastasis was found after 20 months of follow-up. In conclusion, in patients with positive PD-1 ligand 1 expression in primary female urethral squamous cell carcinoma, chemotherapy combined with PD-1 inhibitors may be effective. Larger sample studies are required to determine PD-1 ligand 1 expression and the curative effect of PD-1 inhibitors, as well as their effect on survival.