Table 3:
Univariate and multivariate analysis of factors affecting outcome for patients with SCCs treated with PD-1/PD-L1 blockade [TMB <12 and ≥ 12]. (See Supplementary Table 3 for analysis with TMB stratified by high, intermediate and low) (N=75 patients).
| Variable | Group (N) | SD ≥ 6 months plus PR/CR1 N = 31 (%) | OR2 (95% CI) | P univariate | P multivariate* | Median TTF (mos) | HR2 (95% CI) | P univariate | P multivariate* | Median OS | HR3 (95% CI) | P univariate |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age (years) | <60 (N = 18) | 6 (33%) | 0.6 [0.2–1.8] | 0.5844 | 3.9 | 1.8 [0.9–3.4] | 0.0848 | 11.4 | 1.6 [0.8–3.4] | 0.1724 | ||
| ≥60 (N = 57) | 25 (44%) | 1.6 [0.5–5.0] | 5.0 | 0.6 [0.3–1.2] | 19.7 | 0.6 [0.3–1.3] | ||||||
| Sex | Male (N = 54) | 21 (39%) | 0.7 [0.3–1.8] | 0.6032 | 4.8 | 1.0 [0.5–1.7] | 0.9261 | 17.4 | 1.0 [0.5–2.0] | 0.9157 | ||
| Female (N = 21) | 10 (48%) | 1.4 [0.5–3.7] | 4.8 | 1.0 [0.6–1.8] | 17.4 | 1.0 [0.5–2.2] | ||||||
| Ethnicity | White (N = 61) | 25 (41%) | 0.9 [0.3–3.2] | >0.9999 | 5.0 | 0.8 [0.4–1.5] | 0.4328 | 17.4 | 1.0 [0.4–2.5] | 0.9361 | ||
| Other (N = 14) | 6 (43%) | 1.1 [0.3–3.2] | 2.9 | 1.3 [0.6–2.6] | 11.4 | 1.0 [0.4–2.3] | ||||||
| Disease status | Locally advanced (N = 23) | 10 (43%) | 1.1 [0.4–3.2] | 0.8052 | 5.5 | [0.9 [0.5–1.6] | 0.8419 | 17.4 | 0.7 [0.3–1.4] | 0.3422 | ||
| Metastatic (N = 52) |
21 (40%) | 0.9 [0.3–2.2] | 4.7 | 1.1 [0.6–1.8] | 13.1 | 1.4 [0.7–2.9] | ||||||
| TMB | TMB < 12 mut/mb (N = 21)* | 6 (29%) | 0.3 [0.1–0.9] | 0.0616 | 0.285 | 4.4 | 2.7 [1.3–5.7] | 0.0058 | 0.209 | 12.2 | 1.6 [0.6–3.7] | 0.3243 |
| TMB ≥ 12 mut/mb (N = 20)* | 12 (60%) | 3.8 [1.1–12.3] | 9.9 | 0.3 [0.2–0.7] | 17.4 | 0.6 [0.2–1.5] | ||||||
| Treatment | ≤1 prior therapy (N = 46) |
20 (44%) | 1.3 [0.5–3.4] | 0.8101 | 4.8 | 0.9 [0.5–1.6] | 0.7385 | 19.7 | 0.8 [0.4–1.5] | 0.4657 | ||
| 2 or more prior therapies (N = 29) | 11 (38%) | 0.8 [0.3–2.0] | 5.2 | 1.1 [0.6–1.9] | 12.2 | 1.2 [0.7–2.5] | ||||||
| PD-1/PD-L1 blockade monotherapy (N = 68) |
29 (43%) | 1.9 [0.3–9.8] | 0.6926 | 5.1 | 1.1 [0.4–2.6] | 0.8822 | 17.4 | 0.7 [0.2–2.3] | 0.5067 | |||
| PD-1/PD-L1 blockade + other (N = 7) | 2 (29%) | 0.5 [0.1–2.9] | 4.3 | 0.9 [0.4–2.3] | 8.9 | 1.4 [0.4–4.7 | ||||||
| Histology | Cutaneous SCC (N = 15) |
11 (73%) | 5.5 [1.5–16.9] | 0.008 | 0.459 | Not reached | 0.3 [0.2–0.5] | 0.0015 | 0.397 | Not reached | 0.5 [0.2–1.0] | 0.0593 |
| Non-cutaneous (N = 60) |
20 (33%) | 0.2 [0.1–0.6] | 4.2 | 3.5 [2.0–6.2] | 12.5 | 2.1 [1.0–4.5] |
41 patients were included in the multivariate analysis. P values ≤ 0.1 in univariate were included in the multivariate analysis. Outcome numbers may be different than in Table 1 because only 41 patients with available TMB were included in the multivariate analysis in this table, while in Table 1, all 75 patients were analyzed.
Response included patients with stable disease ≥ 6 months, partial responders, and complete responders
Calculated using Fischer’s exact test
Calculated using long-rank (Mantel-Cox)
Other therapy: chemotherapy (N = 1), targeted therapy (N = 1), and investigational agent (N = 5)
Abbreviations: HR = hazard ratio; mb = megabase; MSI = microsatellite instability; OR = odds ration; OS = overall survival; SCC = squamous cell carcinoma; TMB = tumor mutational burden; TTF = time to treatment failure