Experimental study of 99Tcm-HL91 and 99Tcm-MIBI in mice bearing Lewis lung cancer

Objective: To evaluate the ability of detecting lung cancer by 99Tcm-HL91 and 99Tcm-MIBI in mice bearing Lewis lung cancer. Methods: Four model mice underwent whole body planar imaging at 2 h, 4 h after injection of 99Tcm-MIBI; four mice underwent whole body planar imaging at 2 h and 4 h after injection of 99Tcm-HL91, and the mice of the 99Tcm-HL91 group were then killed, the tumor, blood and organs were removed, weighted and the radioactivity was measured. ROIs were drawn around the tumor, head and chest in whole body planar images, and radioactivity ratios of tumor to head (T/H), chest (T/C) and contralateral limbs (T/L) were calculated. Results: No significant tumor radioactivity in 2 h and 4 h images of 99Tcm-MIBI mice (T/C: 0.20 +- 0.08 and 0.14 +- 0.07) was found; increased tumor radioactivity was identified in images of 99Tcm-HL91 mice (T/C: 3.25 +- 1.25 and 2.44 +- 1.07), and there was significant difference (t = 4.8 - 7.5, P < 0.01) between two groups. The radioactivity ratios in per unit weight of tumor to lung, brain, blood, heart and muscles were much higher than those of tumor to liver, spleen, stomach, intestine and kidney. Conclusions: Retention ratio of 99Tcm-HL91 in tumor tissue of mice is higher and clearance rate is slower. 99Tcm-HL91 is a valuable tumor imaging agent for clinical diagnosis for the cancer