CD8A and neoplasm: A central finding from our study is that the presence of stem cell-like TCF7-expressing CD8+ and absence of HAVCR2-expressing CD8+ exhausted T-cells are indicative of CAR T-cell expansion and antitumor activity in both non-hematopoietic and hematopoietic cancers, suggesting that the intrinsic fitness of the engineered T-cells, in addition to absolute T-cell number and spatial distribution within a patient’s tumor, is crucial for induction of effective tumor immunity.