Radioprotectors in the Management of Lung Cancer

Radiation therapy has become increasingly important in the management of lung cancer at all stages. However, radiotherapy, given alone or with concurrent chemo- and immunotherapy, can have severe adverse effects on critical organs that are often in the path of the radiation beam depending on the location of the tumor. Immune checkpoint inhibitor therapy also has its own adverse effects that include inflammation of the lung (interstitial pneumonitis) and heart (myocarditis, pericarditis). In the randomized phase III PACIFIC clinical trial (Antonia et al. 2018) of lung cancer treated with concurrent chemoradiation therapy to be followed by durvalumab or placebo, only patients who did not develop symptomatic toxicity after the chemoradiation were randomized, which excluded at least 35–40% patients from the potential benefits of checkpoint inhibitor therapy because of concern over severe adverse sequelae. The ability to counteract the toxic effects of radiation, chemotherapy, and immune checkpoint inhibitors in their various combinations is imperative if treatment is to be curative without compromising quality of life.