Demographic and clinical differences in patients by immune checkpoint inhibitor line of treatment
| Characteristic | Overall n=326 | 1L n=80 | 2L n=106 | 3L+ n=140 | P-value |
| Age at diagnosis, median (IQR) | 65.4 (59.4–70.7) | 66.4 (60.7–71.9) | 64.4 (61.0–71.0) | 65.0 (58.9–69.7) | 0.33 |
| Age at initial immune checkpoint inhibitor administration, median (IQR) | 68.3 (62.3–73.9) | 68.2 (62.3–73.8) | 68.2 (63.0–75.0) | 68.6 (61.8–73.7) | 0.83 |
| Race, n (%) | 0.10 | ||||
| White | 217 (66.6) | 48 (60.0) | 70 (66.0) | 99 (70.7) | |
| Black or African American | 52 (16.0) | 15 (18.8) | 13 (12.3) | 24 (17.1) | |
| Asian or Hispanic or Latino | * | * | * | * | |
| Other race | 27 (8.3) | * | 11 (10.4) | 12 (8.6) | |
| Unknown | * | 10 (12.5) | * | * | |
| Region, n (%) | 0.004 | ||||
| Midwest | 35 (10.7) | 9 (11.2) | 19 (17.9) | 7 (5.0) | |
| Northeast | 48 (14.7) | 16 (20.0) | 16 (15.1) | 16 (11.4) | |
| South | 109 (33.4) | 22 (27.5) | 35 (33.0) | 52 (37.1) | |
| West | 34 (10.4) | 11 (13.8) | 13 (12.3) | 10 (7.1) | |
| Unknown | 100 (30.7) | 22 (27.5) | 23 (21.7) | 55 (39.3) | |
| Payer category, n (%) | 0.17 | ||||
| Commercial health plan | 91 (27.9) | 21 (26.2) | 35 (33.0) | 35 (25.0) | |
| Medicare, Medicaid, or other government program | 39 (12.0) | 18 (22.5) | 10 (9.4) | 18 (12.9) | |
| Other† | 138 (42.3) | 33 (41.2) | 45 (41.5) | 60 (42.8) | |
| Practice type, n (%) | 0.06 | ||||
| Academic | 75 (23.0) | 16 (20.0) | 18 (17.0) | 41 (29.3) | |
| Community | 251 (77.0) | 64 (80.0) | 88 (83.0) | 99 (70.7) | |
| ECOG, n (%) | NA | ||||
| 0 | 144 (44.2) | 40 (50.0) | 44 (41.5) | 60 (42.9) | |
| 1 | 102 (31.3) | 19 (23.8) | 36 (34.0) | 47 (33.6) | |
| 2 | 26 (8.0) | * | 13 (12.3) | 10 (7.1) | |
| 3–4 | 6 (1.8) | * | * | * | |
| Unknown | 48 (14.7) | * | * | * | |
| Stage at diagnosis, n (%) | <0.001 | ||||
| I-II | 120 (36.8) | 26 (32.5) | 38 (35.8) | 56 (40.0) | |
| III | 86 (26.4) | 35 (43.8) | 26 (24.5) | 25 (17.9) | |
| IV | 101 (31.0) | 12 (15.0) | 37 (34.9) | 52 (37.1) | |
| Unknown | 19 (5.8) | 7 (8.8) | 5 (4.7) | 7 (5.0) | |
| Prior radiation, n (%) | 0.014 | ||||
| Yes | 128 (39.3) | 38 (47.5) | 43 (40.6) | 47 (33.6) | |
| No | 91 (27.9) | 28 (35.0) | 25 (23.6) | 38 (27.1) | |
| Unknown | 107 (32.8) | 14 (17.5) | 38 (35.8) | 55 (39.3) | |
| Prior radiation modality, n (%) | 0.009 | ||||
| EBRT | 32 (9.8) | 13 (16.2) | 11 (10.4) | 8 (5.7) | |
| Vaginal brachytherapy | 46 (14.1) | 6 (7.5) | 18 (17.0) | 22 (15.7) | |
| Combination EBRT and brachytherapy | 39 (12.0) | 16 (2.0) | 8 (7.5) | 15 (10.7) | |
| Unknown | 209 (64.1) | 45 (56.3) | 69 (65.1) | 95 (67.8) | |
| MMR status, n (%) | 0.22 | ||||
| MSI-H/dMMR | 107 (32.8) | 38 (35.0) | 42 (39.6) | 37 (26.4) | |
| MSI-L/pMMR/MSS | 152 (46.6) | 38 (47.5) | 42 (39.6) | 72 (51.4) | |
| Unknown | 67 (20.6) | 14 (17.5) | 22 (20.8) | 31 (22.1) |
*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 or unknown.
dMMR, mismatch repair deficient; EBRT, external beam radiation therapy; ECOG, Eastern Cooperative Oncology Group; L, first line; 2L, second line; 3L+, third and subsequent lines; MMR, mismatch repair; MSI-H, microsatellite instability-high; MSI-L, microsatellite instability-low; MSS, microsatellite stable; pMMR, mismatch repair proficient.