TABLE 1.
Baseline characteristics at initiation of immune checkpoint inhibitors (ICI) therapy
| Non‐PPI users | PPI users | p value | |
|---|---|---|---|
| n | 56 | 99 | |
| Age, years (IQR) | 73 (65–81) | 71 (63–78) | 0.158 |
| Male, n | 43 (77%) | 75 (76%) | 0.886 |
| UTUC, n | 22 (39%) | 43 (43%) | 0.617 |
| ECOG PS > 1 | 11 (20%) | 23 (23%) | 0.689 |
| Antibiotics (Abs) users | 21 (38%) | 50 (51%) | 0.119 |
| PPI use before the ICI therapy, n | 0 (0%) | 79 (80%) | |
| Local therapy, n | 37 (66%) | 54 (55%) | 0.178 |
| Surgery | 28 (50%) | 45 (45%) | 0.590 |
| Radiotherapy | 13 (23%) | 13 (13%) | 0.132 |
| Outcomes of first‐line therapy | |||
| Carboplatin‐based regimens, n | 34 (61%) | 65 (66%) | 0.743 |
| Number of cycles (IQR) | 2 (2–4) | 3 (2–3) | 0.329 |
| Objective response, n | 16 (29%) | 30 (30%) | 0.839 |
| Treatment line of ICI therapy (IQR) | 2 (2–2) | 2 (2–2) | 0.185 |
| Type of ICI therapy (PD‐1 vs. PD‐L1) | 0.620 | ||
| Pembrolizumab | 49 (88%) | 96 (97%) | |
| Nivolumab | 5 (8.9%) | 1 (1%) | |
| Atezolizumab | 1 (1.8%) | 1 (1%) | |
| Durvalumab | 1 (1.8%) | 1 (1%) | |
| Clinical TNM stage, n | |||
| T4 | 15 (27%) | 38 (38%) | 0.494 |
| N+ | 33 (59%) | 64 (65%) | 0.439 |
| M1 | 38 (68%) | 67 (68%) | 0.982 |
| Number of metastatic sites | 1 (1–2) | 1 (1–2) | 0.355 |
| Number of metastatic sites >1 | 18 (32%) | 38 (31%) | 0.436 |
| eGFR (ml/min/1.73 m2) (IQR) | 48 (40–70) | 51 (40–64) | 0.760 |
| Concomitant use of antibiotics (Abs), n | 21 (38%) | 50 (51%) | 0.118 |
| Disease progression after ICI therapy, n | 26 (46%) | 70 (71%) | |
| Deceased, n | 21 (38%) | 60 (61%) | |
eGFR, estimated glomerular filtration rate; ICI, immune checkpoint inhibitor; IQR, interquartile range; PD‐1, programmed cell death 1; PD‐L1, programmed cell death ligand 1; PPI, proton pump inhibitor; UTUC, upper tract urothelial carcinoma.