Table 2.
Univariate analysis of factors affecting outcome for patients treated with immune checkpoint blockade (N = 83)
| Rate of SD ≥ 6 month/PR/CR1 | PFS | OS | ||||||
|---|---|---|---|---|---|---|---|---|
| Variable | N (%) | P value2 | Median, months | HR (95% CI) | P value3 | Median, months | HR (95% CI) | P value3 |
| Sex | ||||||||
| Male (N = 46) vs. female (N = 37) | 23 (51%) vs. 13 (35%) | 0.18 | 6.3 vs. 4.1 | 0.63 (0.38–1.04) | 0.07 | NR (MFU, 19.1) vs. 12.0 | 0.51 (0.27–0.95) | 0.03 |
| Ethnicity | ||||||||
| Caucasian (N = 71) vs. others4 (N = 12) | 32 (45%) vs. 4 (36%) | 0.75 | 4.9 vs. 2.9 | 0.52 (0.26–1.00) | 0.045 | 18.5 vs. 8.2 | 0.45 (0.19–1.06) | 0.004 |
| Age5, years | ||||||||
| < 60 (N = 17) vs. ≥ 60 (N = 66) | 6 (35%) vs. 30 (46%) | 0.58 | 3.5 vs. 5.1 | 1.29 (0.70–2.39) | 0.41 | 12.0 vs. 14.9 | 0.86 (0.36–2.06) | 0.73 |
| Tumor type | ||||||||
| Head and neck SCC (N = 9) vs. not (N = 74) | 4 (44%) vs. 32 (44%) | > 0.99 | 4.8 vs. 4.9 | 1.01 (0.46–2.22) | 0.99 | 12.9 vs. 16.6 | 1.11 (0.43–2.84) | 0.83 |
| NSCLC (N = 26) vs. not (N = 57) | 8 (31%) vs. 28 (50%) | 0.15 | 3.0 vs. 6.0 | 1.67 (0.99–2.81) | 0.05 | 9.3 vs. 16.6 | 1.37 (0.71–2.64) | 0.34 |
| Cutaneous SCC (N = 10) vs. not (N = 73) | 7 (70%) vs. 29 (40%) | 0.10 | 26.8 vs. 4.7 | 0.43 (0.17–1.08) | 0.06 | NR (median follow-up, 21.7) vs. 13.9 14.9 vs. 17.1 | 0.43 (0.13–1.40) | 0.15 |
| Others6 (N = 38) vs. head and neck SCC, NSCLC, and cutaneous SCC (N = 45) | 17 (46%) vs. 19 (42%) | 0.82 | 5.1 vs. 4.8 | 0.91 (0.55–1.52) | 0.72 | 1.02 (0.54–1.93) | 0.95 | |
| TMB7, mutations/mb | ||||||||
| ≥ 50 (N = 12) vs. < 50 (N = 65) | 9 (75%) vs. 25 (39%) | 0.03 | 26.8 vs. 4.4 | 0.40 (0.17–0.94) | 0.03 | NR (median follow-up, 17.5) vs. 12.9 | 0.39 (0.12–1.27) | 0.10 |
| ≥ 20 (N = 21) vs. < 20 (N = 56) | 14 (67%) vs. 20 (36%) | 0.02 | 14.1 vs. 4.2 | 0.45 (0.23–0.85) | 0.01 | NR (median follow-up, 22.4) vs. 12.0 | 0.42 (0.19–0.96) | 0.03 |
| ≥ 10 (N = 39) vs. < 10 (N = 38) | 23 (59%) vs. 11 (29%) | 0.01 | 6.9 vs. 4.0 | 0.40 (0.23–0.68) | 0.001 | 37.1 vs. 10.1 | 0.42 (0.21–0.82) | 0.009 |
| PHBR | ||||||||
| < 0.5 (N = 32) vs. ≥ 0.5 (N = 51) | 17 (53%) vs. 19 (38%) | 0.25 | 5.1 vs. 4.4 | 0.58 (0.34–0.99) | 0.04 | NR (median follow-up, 21.7) vs. 14.9 | 0.66 (0.34–1.27) | 0.21 |
| PD-1/L1 therapy | ||||||||
| Monotherapy (N = 66) vs. combination (N = 17) | 25 (39%) vs. 11 (65%) | 0.06 | 4.1 vs. 6.3 | 1.17 (0.63–2.16) | 0.63 | 17.1 vs. 11.3 | 0.78 (0.37–1.66) | 0.51 |
1Thirty-six patients achieved SD with ≥ 6 months/PR/CR. One patient attained ongoing SD, but has not yet reached 6-month follow-up and is therefore not considered evaluable for this parameter; only 82 patients were evaluable for this comparison
2Calculated using Fisher’s exact test
3Calculated using the log-rank test
4Others: African American (N = 2), Asian (N = 4), Hispanic (N = 5), and unknown (N = 1)
5At time of initiation of treatment with immunotherapy
6Others: adrenal (N = 1), appendix (N = 4), basal cell carcinoma (N = 3), breast cancer (N = 6), cervical (N = 1), cholangiocarcinoma (N = 1), colorectal (N = 2), duodenal (N = 1), gastroesophageal (N = 5), glioblastoma (N = 2), thyroid (N = 1), prostate (N = 1), rectal squamous cell carcinoma (N = 1), renal cell carcinoma (N = 1), sarcoma (N = 3), urothelial (N = 4), and urethral squamous cell carcinoma (N = 1)
7Seventy-seven patients with TMB were evaluable for the response rate, PFS, and OS
Abbreviations: HR hazard ratio, NR not reached to 50%, NSCLC non-small cell lung cancer, OS overall survival, PFS progression-free survival, PHBR Patient Harmonic-mean Best Rank, SCC squamous cell carcinoma, TMB tumor mutational burden