Disitamab vedotin combined with PD-1 inhibitors for postoperative adjuvant therapy in upper tract urothelial carcinoma: a retrospective exploratory case series.

Upper tract urothelial carcinoma (UTUC) carries a high risk of postoperative recurrence; however, the decline in renal function following radical nephroureterectomy often limits the use of cisplatin-based chemotherapy. While the combination of disitamab vedotin and PD-1 inhibitors has demonstrated antitumor activity in advanced urothelial carcinoma, evidence regarding its use as postoperative adjuvant therapy remains limited. This study retrospectively identified patients with UTUC who underwent radical resection with R0 margins and had no distant metastasis prior to treatment, and who subsequently received disitamab vedotin combined with a PD-1 inhibitor due to unsuitability for or refusal of platinum-based chemotherapy. A total of seven patients were included; all were male, with a median age of 65 years. Pathological analysis confirmed pure urothelial carcinoma without histological variants in all cases. Four patients exhibited high-risk features (≥pT3 stage or lymph node positivity); all cases showed HER2 expression of IHC 2+ or 3+ and PD-L1 expression <1%. All patients completed four cycles of the combination therapy. With a median follow-up of 22.3 months, three recurrences and two deaths occurred, including three cases of local recurrence. The 12-month postoperative recurrence-free survival (RFS) rate was 71.4%, and the median RFS had not yet been reached. Treatment-related adverse events (TRAEs) of any grade and Grade ≥3 TRAEs occurred in four and two patients, respectively; no Grade 4-5 adverse events or treatment-related deaths were observed. These results provided a preliminary description of the practical feasibility and observed safety of this regimen in a specific cohort of postoperative UTUC patients; however, given the very small sample size and the lack of a control group, no conclusions regarding therapeutic efficacy could be drawn, and further prospective studies are required for evaluation.