Glycyrrhizic Acid Mitigates 2nd Round Radiotherapy-Induced Severe Lung Injury: A Case Report

Irradiation (IR) has become more important and effective therapeutic approach for cancer in chest (lung, breast and esophagus), however, IR-induced pneumonitis/fibrosis is still the bottle-neck for using higher IR dose to more effectively eradicate cancer cells, since there is no drug to treat the companion IR-injury toxicity. Glycyrrhizic Acid (GLA) has been used to treat hepatitis and liver fibrosis for almost 3 decades in Asia. It has no lethal dose in animal and no obvious side effect in human, which allows for 2 to 3 month use to imitate chronic fibrosis. Here we report for the first time that while GLA was used to treat the liver damage caused by chemotherapy, it presented a surprising mitigation effect on a 2nd round IR treatment-induced severe lung injury in a recurrent stage B (T2N3M0) lung cancer patient who had severe pneumonitis during the 1st round IR therapy. Combined with the fact that GLA effectively mitigates IR induced pneumonitis/fibrosis in animal model, we conclude that GLA is a potential good candidate to be developed as anti-IR lung injury drug.