Table 2. Event counts, frequencies, and risks of non-infectious pneumonitis for patients with advanced non-small cell lung cancer treated with radiation therapy and immune checkpoint inhibition.
| Treatment | Events/Total | Frequencies (95% CI) |
Hazard ratio (95% CI) | RERI (95% CI), P value* | |||
|---|---|---|---|---|---|---|---|
| Unadjusted | Adjusted | Unadjusted | Adjusted | ||||
| Control | 28/9,345 | 0.3% (0.2, 0.4) | Reference | Reference | – | – | |
| RT | 296/7,553 | 3.9% (3.5, 4.4) | 11.5 (7.9, 17.0) | 9.5 (6.4, 14.0) | – | – | |
| ICI | 33/1,332 | 2.5% (1.8, 3.5) | 6.2 (3.8, 10.3) | 6.2 (3.7, 10.2) | – | – | |
| RT + ICI | 19/550 | 3.5% (2.2, 5.4) | 10.7 (6.0, 19.2) | 10.6 (5.9, 19.0) | −6.1 (−13.1, −0.6), P=0.89 | −4.0 (−10.7, 1.5), P=0.91 | |
Adjusted models control for age at diagnosis, sex, histology, AJCC stage, brain metastases at diagnosis, and history of chronic obstructive pulmonary disease. *, hypothesis testing for RERI compared estimate to a null hypothesis of RERI ≤0. RT, radiation therapy; ICI, immune checkpoint inhibition; RERI, relative excess risk due to interaction; 95% CI, 95% confidence interval; AJCC, American Joint Commission on Cancer.