Pre-clinical and clinical studies have demonstrated that radiolabeled PARP-1 ligands are capable of measuring PARP expression in tumors [9], quantifying the efficacy of several FDA-approved PARP-1 inhibitors in lung cancer in vitro and in vivo [10], and monitoring PARP-1 expression in response to radiation therapy [11]. The gene discussed is PARP1; the disease is lung carcinoma.