This patient was then treated in a dedicated small cell cancer clinic with an ATR inhibitor (berzosertib) in combination with a Trop-2 antibody and topoisomerase inhibitor conjugate (sacituzumab govitecan) and subsequently with berzosertib in combination with a standard second-line small cell chemotherapy (topotecan) as part of a clinical trial (see Fig. 3A). This evidence concerns the gene ATR and cancer.