The accumulation of 99mTc-HYNIC-MPG in the PC9 tumor was significantly decreased at the presence of 100 mg/Kg PD153035 and the T/M ratio was also decreased to 2.51 ± 0.30 (Figure 3), suggesting that high uptake of 99mTc-HYNIC-MPG in the PC9 tumor is related to the EGFR-activating mutation. The gene discussed is EGFR; the disease is neoplasm.