Table 1.
Baseline characteristics
| Characteristic | N | % |
| Median age, years (range) | 64 (34–80) | |
| Sex | ||
| Male | 39 | 79.6 |
| Female | 10 | 20.4 |
| Race | ||
| White | 44 | 89.8 |
| Black or African American | 2 | 4.1 |
| Asian | 1 | 2.0 |
| Other | 1 | 2.0 |
| More than one race | 1 | 2.0 |
| ECOG performance status | ||
| 0 | 13 | 26.5 |
| 1 | 36 | 73.5 |
| Histology at baseline | ||
| Squamous cell carcinoma | 10 | 20.4 |
| Adenocarcinoma (including one adenosquamous) | 39 | 79.6 |
| Metastatic disease | ||
| Yes | 45 | 91.8 |
| No | 4 | 8.2 |
| Prior radiation therapy | ||
| Received | 33 | 67.3 |
| Not received (or unknown) | 16 | 32.7 |
| Prior lines of therapy | ||
| 0 | 0 | 0.0 |
| 1 | 10 | 20.4 |
| 2 | 13 | 26.5 |
| 3 | 9 | 18.4 |
| 4 | 8 | 16.3 |
| ≥5 | 7 | 14.3 |
| Missing | 2 | 4.1 |
| HER2 (EAC only) | ||
| Negative | 29 | 74.4 |
| Positive | 9 | 23.1 |
| Unknown | 1 | 2. |
| MMR status | ||
| MMR proficient | 9 | 18.4 |
| MLH1 proficient, not tested otherwise | 1 | 2.0 |
| MMR deficient | 1 | 2.0 |
| Unknown | 38 | 77.6 |
ECOG, Eastern Cooperative Oncology Group; MMR, mismatch repair.