Table 1.
Demographics and baseline characteristics of the study cohort
| FAS | PP population | |||||
|---|---|---|---|---|---|---|
| Placebo-chemo | Atezo-chemo | P value | Placebo-chemo | Atezo-chemo | P value | |
| (n = 28) | (n = 40) | (n = 23) | (n = 36) | |||
| Age | 0.16 | 0.17 | ||||
| Median (range) | 52.5 (28.0–74.0) | 58.5 (31.0–77.0) | 52.0 (28.0–74.0) | 59.0 (31.0–77.0) | ||
| Gender | 0.40 | 0.42 | ||||
| Female | 28 (100%) | 39 (97.5%) | 23 (100%) | 35 (97.2%) | ||
| Male | 0 (0%) | 1 (2.5%) | 0 (0%) | 1 (2.8%) | ||
| ECOG performance status | 0.50 | 0.99 | ||||
| 0 | 21 (75.0%) | 27 (67.5%) | 16 (69.6%) | 25 (69.4%) | ||
| 1 | 7 (25.0%) | 13 (32.5%) | 7 (30.4%) | 11 (30.6%) | ||
| De novo metastatic disease | 0.74 | 0.93 | ||||
| Yes | 8 (28.6%) | 10 (25.0%) | 6 (26.1%) | 9 (25.0%) | ||
| No | 20 (71.4%) | 30 (75.0%) | 17 (73.9%) | 27 (75.0%) | ||
| Bone metastases | 0.23 | 0.18 | ||||
| Yes | 16 (57.1%) | 17 (42.5%) | 13 (56.5%) | 14 (38.9%) | ||
| No | 12 (42.9%) | 23 (57.5%) | 10 (43.5%) | 22 (61.1%) | ||
| Liver metastases | 0.17 | 0.36 | ||||
| Yes | 13 (46.4%) | 12 (30.0%) | 9 (39.1%) | 10 (27.8%) | ||
| No | 15 (53.6%) | 28 (70.0%) | 14 (60.9%) | 26 (72.2%) | ||
| Lung metastases | 0.44 | 0.69 | ||||
| Yes | 10 (35.7%) | 18 (45.0%) | 9 (39.1%) | 16 (44.4%) | ||
| No | 18 (64.3%) | 22 (55.0%) | 14 (60.9%) | 20 (55.6%) | ||
| Lymph node metastases | 0.49 | 0.94 | ||||
| Yes | 13 (46.4%) | 22 (55.0%) | 13 (56.5%) | 20 (55.6%) | ||
| No | 15 (53.6%) | 18 (45.0%) | 10 (43.5%) | 16 (44.4%) | ||
| CNS metastases | 0.80 | 0.75 | ||||
| Yes | 1 (3.6%) | 1 (2.5%) | 1 (4.3%) | 1 (2.8%) | ||
| No | 27 (96.4%) | 39 (97.5%) | 22 (95.7%) | 35 (97.2%) | ||
| Number of metastatic sites | 0.24 | 0.12 | ||||
| ≤2 | 15 (53.6%) | 27 (67.5%) | 12 (52.2%) | 26 (72.2%) | ||
| >2 | 13 (46.4%) | 13 (32.5%) | 11 (47.8%) | 10 (27.8%) | ||
| >3 | 3 (10.7%) | 7 (17.5%) | 3 (13.0%) | 5 (13.9%) | ||
| Line of chemotherapy | 0.81 | 0.37 | ||||
| 1st | 16 (57.1%) | 24 (60.0%) | 12 (52.2%) | 23 (63.9%) | ||
| 2nd | 12 (42.9%) | 16 (40.0%) | 11 (47.8%) | 13 (36.1%) | ||
| Previous anthracycline treatment | 0.90 | 0.71 | ||||
| Yes | 20 (71.4%) | 28 (70.0%) | 17 (73.9%) | 25 (69.4%) | ||
| No | 8 (28.6%) | 12 (30.0%) | 6 (26.1%) | 11 (30.6%) | ||
| PD-L1 status | 0.22 | 0.22 | ||||
| Negative | 17 (60.7%) | 19 (47.5%) | 14 (60.9%) | 17 (47.2%) | ||
| Positive | 10 (35.7%) | 21 (52.5%) | 8 (34.8%) | 19 (52.8%) | ||
| Missing | 1 (3.6%) | 0 (0%) | 1 (4.3%) | 0 (0%) | ||
| Intrinsic breast cancer subtype | 0.44 | 0.48 | ||||
| Luminal A | 2 (7.1%) | 0 (0%) | 2 (8.7%) | 0 (0%) | ||
| Luminal B | 1 (3.6%) | 1 (2.5%) | 1 (4.3%) | 1 (2.8%) | ||
| HER2-enriched | 2 (7.1%) | 4 (10.0%) | 2 (8.7%) | 4 (11.1%) | ||
| Basal | 12 (42.9%) | 22 (55.0%) | 11 (47.8%) | 20 (55.6%) | ||
| Missing | 11 (39.3%) | 13 (32.5%) | 7 (30.4%) | 11 (30.6%) | ||
| BRCA mutation status | 0.54 | 0.54 | ||||
| BRCA1 mutation | 1 (3.6%) | 2 (5.0%) | 1 (4.3%) | 2 (5.6%) | ||
| Normal variant | 12 (42.9%) | 22 (55.0%) | 11 (47.8%) | 22 (61.1%) | ||
| Missing | 15 (53.6%) | 16 (40.0%) | 11 (47.8%) | 12 (33.3%) | ||
Two-sided P values were calculated using the Wilcoxon rank-sum test to compare age distributions and the chi-square test for all other variables. In comparison of the number of metastatic sites, only the first two groups were included in the chi-square test owing to the overlap between the two latter groups.