Abstract 301P
Background
Although radical surgery is the standard treatment for patients with high-risk urothelial carcinoma (UC), it is estimated that half of these patients experience metastatic recurrence within 1 year. The phase III CheckMate 274 trial demonstrated the superiority of adjuvant nivolumab over placebo in these patients, showing a 30% reduction in risk of recurrence or death compared to placebo. The aim of this study is to describe the effectiveness and safety profile of real-world patients with high-risk UC in Japan.
Methods
Between 2022 and 2024, 33 Japanese patients with high-risk UC received adjuvant nivolumab therapy following radical surgery at our institution.
Results
Eight patients (24%) had upper urinary tract cancers. All but one patient received prior neoadjuvant chemotherapy. A total of 23 (70%) and 13 patients (39%) had pT3-4 and pN1-2 disease, respectively. Any-grade immune-related adverse events (irAEs) occurred in 9 patients (27%), with 3 patients experiencing Grade 3 irAEs (2 cases of interstitial lung disease and 1 case of dermatitis). No Grade 4-5 irAEs were observed. During the follow-up period (median:11months), 8 cases showed recurrences and 1 case died of cancer. The 1-year overall survival (OS) rate was 100%, and the 6-month and 1-year recurrence-free survival (RFS) rates were 89% and 70%, respectively. Eight of the 33 patients have completed 1 year of treatment, and 9 patients are currently on treatment. There were 16 cases (48%) who discontinued adjuvant nivolumab therapy, of whom 6, 7, and 3 experienced recurrence during administration, irAE, and other AEs, respectively. Table: 301P
| Characteristics | no. (%) |
| Age: Median (range) | 69(50-82) |
| Gender: Male/Female | 24(73%)/9(27%) |
| Race: Asian | 33(100%) |
| ECOG PS: 0/1/2 | 29(88%)/3(9%)/1(3%) |
| Tumor Origin: Bladder/Renal pelvis/Ureter | 25(76%)/4(12%)/4(12%) |
| Prior neoadjuvant chemotherapy | 32(97%) |
| pTis/1/2/3/4 | 2(6%)/1(3%)/7(21%)/18(55%)/5(15%) |
| pN0/1/2/x | 19(58%)/6(18%)/7(21%)/1(3%) |
| Outcomes | |
| irAEs G1-2/3/4-5 | 6(18%)/3(9%)/0(0%) |
| Recurrences | 8(24%) |
| Death | 1(3%) |
Conclusions
Adjuvant nivolumab appears to be effective in Japanese patients, with the RFS in our cohort being better than that in the CheckMate 274 trial. Further studies with larger cohorts are needed.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.