Features of steroid-sensitive, infliximab-sensitive and infliximab-refractory groups
| Overall (n=115)* | Steroid sensitive (n=54) | Infliximab sensitive (n=47) | Infliximab refractory (n=13) | P value | |
| Age (years) | 0.12 | ||||
| Median (range) | 62 (30,92) | 64 (37,84) | 61 (30,92) | 68 (38,76) | |
| Gender, n.(%) | 0.28 | ||||
| Male | 75 (65.2) | 39 (72.2) | 27 (57.4) | 9 (69.2) | |
| Female | 40 (34.8) | 15 (27.8) | 20 (42.6) | 4 (30.8) | |
| History of autoimmune, n (%) disease | 0.05 | ||||
| No | 101 (88.6) | 48 (88.9) | 44 (93.6) | 9 (69.2) | |
| Yes | 13 (11.4) | 6 (11.1) | 3 (6.4) | 4 (30.8) | |
| Type of immunotherapy, n (%) | 0.09 | ||||
| IPI+PD1 | 80 (69.6) | 32 (59.3) | 37 (78.7) | 10 (76.9) | |
| PD1 | 35 (30.4) | 22 (40.7) | 10 (21.3) | 3 (23.1) | |
| Colitis grade, n (%) | <0.001 | ||||
| G1 and G2 | 51 (44.3) | 36 (66.7) | 13 (27.7) | 1 (7.7) | |
| G3 and G4 | 64 (55.7) | 18 (33.3) | 34 (72.3) | 12 (92.3) | |
| Time to colitis (weeks) | 0.47 | ||||
| Median (range) | 6.5 (0.5,145.7) | 8.4 (1.5,145.7) | 5.5 (0.5, 140.4) | 7.8 (3.2,55.3) | |
| Dose of steroid (max), n (%) | <0.001 | ||||
| ≤50 mg | 17 (14.9) | 15 (27.8) | 2 (4.3) | 0 (0) | |
| ≥75 mg | 97 (85.1) | 39 (72.2) | 45 (95.7) | 13 (100) | |
| Intravenous pulse steroid | <0.001 | ||||
| No | 63 (55.3) | 40 (74.1) | 17 (36.2) | 6 (46.2) | |
| Yes | 51 (44.7) | 14 (25.9) | 30 (63.8) | 7 (53.8) | |
| Reinitiation of PD1 monotherapy, n (%) | 0.08 | ||||
| No | 71 (62.3) | 38 (66.7) | 25 (53.2) | 11 (84.6) | |
| Yes | 43 (37.7) | 19 (33.3) | 22 (46.8) | 2 (15.4) | |
| Recurrence of colitis, n (%) | 0.01 | ||||
| No | 98 (86.0) | 51 (94.4) | 35 (74.5) | 12 (92.3) | |
| Yes | 16 (14.0) | 3 (5.5) | 12 (25.5) | 1 (7.7) | |
| Endoscopic features | n=64 | n=24 | n=31 | n=9 | |
| Type of treatment to endoscopy | 0.006 | ||||
| Oral steroid only | 39 (60.9) | 18 (75.0) | 18 (58.1) | 3 (33.3) | |
| Oral +intravenous steroid | 20 (31.3) | 4 (16.7) | 12 (38.7) | 4 (44.4) | |
| Steroid +infliximab | 2 (3.1) | 0 (0.0) | 0 (0.0) | 2 (22.2) | |
| None | 3 (4.7) | 2 (8.3) | 1 (3.2) | 0 (0.0) | |
| Degree of inflammation, n (%) | 0.56 | ||||
| Absent | 17 (26.6) | 8 (33.3) | 7 (22.6) | 2 (22.2) | |
| Mild | 22 (34.4) | 10 (41.7) | 10 (32.3) | 2 (22.2) | |
| Moderate | 23 (35.9) | 5 (20.8) | 13 (41.9) | 5 (55.6) | |
| Severe | 2 (3.1) | 1 (4.2) | 1 (3.2) | 0 (0.0) | |
| Pattern of inflammation, n (%) | 0.13 | ||||
| Diffuse | 19 (29.7) | 4 (16.7) | 13 (41.9) | 2 (22.2) | |
| Patchy | 17 (26.6) | 7 (29.2) | 9 (29.0) | 1 (11.1) | |
| Confluent | 11 (17.2) | 4 (16.7) | 3 (9.7) | 4 (44.4) | |
| Absent | 17 (26.6) | 9 (37.5) | 6 (19.4) | 2 (22.2) | |
| Area of colon affected | 0.09 | ||||
| Rectum | 4 (6.3) | 1 (4.2) | 3 (9.7) | 0 (0.0) | |
| Sigmoid | 15 (23.4) | 7 (29.2) | 7 (22.6) | 1 (11.1) | |
| Left colon | 14 (21.9) | 4 (16.7) | 10 (32.3) | 0 (0.0) | |
| Right colon | 3 (4.7) | 2 (8.3) | 1 (3.2) | 0 (0.0) | |
| Pancolitis | 15 (23.4) | 4 (16.7) | 5 (16.1) | 6 (66.7) | |
| None | 13 (20.3) | 6 (25.0) | 5 (16.1) | 2 (22.2) | |
| Ulcer | 0.07 | ||||
| Absent | 48 (75.0) | 19 (79.2) | 25 (80.6) | 4 (44.4) | |
| Few | 7 (10.9) | 3 (12.5) | 1 (3.2) | 3 (33.3) | |
| Multiple | 9 (14.1) | 2 (8.3) | 5 (16.1) | 5 (55.6) | |
| Histopathology, n (%) | n=64 | n=24 | n=31 | n=9 | |
| Chronic inflammatory infiltrate, n (%) | 0.85 | ||||
| No increase | 9 (14.1) | 5 (20.8) | 3 (9.7) | 1 (11.1) | |
| Mild/equivocal increase | 27 (42.2) | 11 (45.8) | 12 (38.7) | 4 (44.4) | |
| Moderate increase | 25 (39.1) | 7 (29.2) | 14 (45.2) | 4 (44.4) | |
| Marked increase | 3 (4.7) | 1 (4.2) | 2 (6.5) | 0 (0.0) | |
| Lamina proprianeutrophils, n (%) | 0.03 | ||||
| No increase | 17 (26.6) | 10 (41.7) | 5 (16.1) | 2 (22.2) | |
| Mild/equivocal increase | 24 (37.5) | 10 (41.7) | 10 (32.3) | 4 (44.4) | |
| Moderate increase | 19 (29.7) | 4 (16.7) | 14 (45.2) | 1 (11.1) | |
| Marked increase | 4 (6.3) | 0 (0.0) | 2 (6.5) | 2 (22.2) | |
| Intraepithelial neutrophilic infiltrate, n (%) | 0.14 | ||||
| Absent | 19 (29.7) | 11 (45.8) | 6 (19.4) | 2 (22.2) | |
| <5% crypts involved | 22 (34.4) | 9 (37.5) | 9 (29.0) | 4 (44.4) | |
| <50% crypts involved | 13 (20.3) | 3 (12.5) | 9 (29.0) | 1 (11.1) | |
| >50% crypts involved | 10 (15.6) | 1 (4.2) | 7 (22.6) | 2 (22.2) | |
| Neutrophilic crypt abscesses, n (%) | 0.02 | ||||
| Absent | 40 (62.5) | 21 (87.5) | 15 (48.4) | 4 (44.4) | |
| <5% crypts involved | 13 (20.3) | 3 (12.5) | 7 (22.6) | 3 (33.3) | |
| <50% crypts involved | 8 (12.5) | 0 (0.0) | 7 (22.6) | 1 (11.1) | |
| >50% crypts involved | 3 (4.7) | 1 (3.8) | 2 (6.5) | 1 (11.1) | |
| Erosion | 0.001 | ||||
| Absent | 51 (79.7) | 24 (100) | 22 (71.0) | 5 (55.6) | |
| Present | 13 (20.3) | 0 (0.0) | 9 (29.0) | 4 (44.4) | |
*Excluded one patient who received no steroid treatment.
IPI, ipilimumab; PD1, programmed cell death protein 1.