Efficacy and safety of neoadjuvant immunotherapy combined with chemotherapy in patients with high-risk UTUC.

Abstract

e16609 Background: Urothelial carcinomas (UCs) are the sixth most common tumor. Among them, UTUCs are uncommon, accounting for only 5-10% of UCs. Currently, radical nephroureterectomy (RNU) remains the gold standard of treatment for UTUC. Neoadjuvant chemotherapy treatment can be used for specific UTUC patients, especially for highly staged and/or grade tumors, such as kidneys with potentially decreased renal function after RNU. Neoadjuvant therapy is a series of treatments administered preoperatively for UTUC, mainly chemotherapy, and in recent years, novel therapies of immunotherapy have emerged. Since conventional cisplatin neoadjuvant regimens also require high preoperative renal function, neoadjuvant chemotherapy regimens such as immunotherapy provide more effective and feasible treatments for patients who are intolerant to current cisplatin chemotherapy regimens. However, there is a lack of valuable studies worldwide on novel regimens such as immunotherapy for UTUC. The aim of this study was to explore a novel preoperative neoadjuvant regimen of immunotherapy combined with chemotherapy for UTUC. To further observe the feasibility and effectiveness of this regimen in the field. Methods: 9 high-risk UTUC patients were included in this study. Among them, 7 had unilateral ureteral tumors. 1 had a unilateral renal pelvic tumor. 1 had unilateral pelvic ureteral tumor. Among them, 2 were combined with bladder tumor. All patients were given 3 cycles of tislelizumab 200 mg combined with albumin paclitaxel 200 mg after a thorough evaluation. The treatment cycles were 21 days. Imaging evaluation and surgical resection were given within 15-20 days after the end of the last treatment cycle. Results: 3 patients underwent radical nephroureterectomy with postoperative pathology suggesting SD status of the tumor. 1 patient underwent ureteral reimplantation with tumor-negative postoperative pathology (cCR) and 2 patients underwent ureteroscopic biopsy, 1 of whom had tumor-negative pathology (cCR). 2 patients declined surgical treatment with RNU, one patient had imaging confirmation that the tumor was in SD, and the other showed no evidence of tumor presence on imaging and cytology (cCR). 1 patient was treated intermittently for grade 2 myocardial adverse effects (the remaining patients had adverse effects mostly limited to grade 1, with alopecia and malaise as common symptoms). Conclusions: The characteristics of epithelial carcinoma of the upper urinary tract have led to a reduced intention of some patients to undergo RNU treatment after the completion of NAC treatment. Although the present study failed to obtain ideal pathological information after RNU, the clinical treatment effect (cCR 30%) presented in combination with imaging and cytological results reveals to some extent the promising prospect of future UTUC patients treated with NAC.