CD4 and neoplasm: Absolute number of (C) CD4 and (D) CD8 T cells normalized to weight of lungs of tumor bearing CCSP-rtTA; TetO-EGFRL858R or CCSP-rtTA; TetO-EGFRL858R + T790M mice in the absence (−) and presence (+) of erlotinib for 2 weeks or taken off doxycycline diet.