Demographic and clinical differences in patients who had never received vs ever received immune checkpoint inhibition
| Characteristic | Never received immune checkpoint inhibitors n=1826 | Ever received immune checkpoint inhibitors n=326 | P-value |
| Age at diagnosis, median (IQR) | 66 (59.6–71.9) | 65.4 (59.5–70.7) | 0.21 |
| Age at initial immune checkpoint inhibition administration, median (IQR) | NA | 68.3 (62.3–73.9) | |
| Race, n (%) | 0.47 | ||
| White | 1147 (62.8) | 217 (66.6) | |
| Black or African American | 302 (16.5) | 52 (16.0) | |
| Asian or Hispanic or Latino | 38 (2.1) | * | |
| Other race | 181 (9.9) | 27 (8.3) | |
| Unknown | 158 (8.7) | * | |
| Region, n (%) | 0.52 | ||
| Midwest | 242 (13.3) | 35 (10.7) | |
| Northeast | 219 (12.0) | 48 (14.7) | |
| South | 622 (43.1) | 109 (33.4) | |
| West | 201 (11.0) | 34 (10.4) | |
| Unknown | 542 (29.7) | 100 (30.7) | |
| Payer category, n (%) | 0.86 | ||
| Commercial health plan | 491 (26.9) | 91 (27.9) | |
| Medicare, Medicaid, or other government program | 319 (17.5) | 46 (14.1) | |
| Other† | 279 (15.3) | 56 (17.2) | |
| Unknown | 737 (40.4) | 133 (40.8) | |
| Practice type, n (%) | 0.43 | ||
| Academic | 381 (20.9) | 75 (23.0) | |
| Community | 1445 (79.1) | 251 (77.0) | |
| ECOG, n (%) | 0.001 | ||
| 0 | 649 (35.5) | 144 (44.2) | |
| 1 | 504 (27.6) | 102 (31.3) | |
| 2 | 179 (9.8) | 26 (8.0) | |
| 3–4 | 69 (3.8) | 6 (1.8) | |
| Unknown | 425 (23.3) | 48 (14.7) | |
| Stage at diagnosis, n (%) | 0.002 | ||
| I | 525 (28.8) | 111 (34.0) | |
| II | 82 (4.5) | 9 (2.8) | |
| III | 361 (19.8) | 86 (26.4) | |
| IV | 725 (39.7) | 101 (31.0) | |
| Unknown | 133 (7.3) | 19 (5.8) | |
| Prior radiation, n (%) | <0.001 | ||
| Yes | 524 (28.7) | 128 (39.3) | |
| No | 519 (28.4) | 91 (27.9) | |
| Unknown | 783 (42.9) | 107 (32.8) | |
| Prior radiation modality, n (%) | 0.003 | ||
| External beam radiation therapy | 111 (6.1) | 32 (3.4) | |
| Vaginal brachytherapy | 199 (10.9) | 46 (14.1) | |
| Combination EBRT and brachytherapy | 163 (8.9) | 39 (12.0) | |
| Unknown | 1352 (74.0) | 209 (94.1) | |
| MMR status, n (%) | <0.001 | ||
| MSI-H/dMMR | 155 (8.5) | 107 (32.8) | |
| MSI-L/pMMR/MSS | 613 (33.6) | 152 (46.6) | |
| Unknown | 1058 (57.9) | 67 (20.6) |
*Column percentages may not equal 100% due to masking cells with fewer than 5 patients (1.5%) to preserve patient privacy.
†Other payer categories include patient assistance programs and self-pay.
dMMR, mismatch repair deficient; EBRT, external beam radiation therapy; ECOG, Eastern Cooperative Oncology Group; IQR, interquartile range; MMR, mismatch repair; MMR, mismatch repair; MSI-H, microsatellite instability-high; MSI-L, microsatellite instability-low; MSS, microsatellite stable; NA, not applicable; pMMR, mismatch repair proficient.