ADH1A and neoplasm: The ROI analysis of the ratio of radioactivity intensity at tumor sites to the radioactivity intensity at adjacent muscles (T/N) showed that the T/N of the uptake of 99mTc-HYNIC-ADH-1 by the PC9GR tumor was 7.73 ± 0.54 at 1 h, which was higher than the T/N of the PC9 tumor (3.66 ± 0.78).