Noninvasive scintigraphic detection of tumor with 99mTc-DTPA-deoxyglucose: an experimental study

Glucosamine is a highly attractive scaffold for a glucosyl ligand, and shows activity with glucose transporters and hexokinase. In the study reported here, diethylenetriamine-pentaacetic acid-D-glucosamine (DTPA-DG) was synthesized by conjugating D-glucosamine to DTPA, and was labeled with technetium-99m ((99m)Tc). We investigated (99m)Tc-DTPA-DG for tumor detection.

The biodistribution and imaging of (99m)Tc-DTPA-DG in mammary tumor-bearing mice were compared to those in a control group of mice with oleum terebinthinae (turpentine oil)-induced inflammation. Both groups of mice were given an intravenous injection of 3.7 MBq/0.1 mL of (99m)Tc-DTPA-DG through the tail vein.

(99m)Tc-DTPA-DG accumulated in the tumor tissue to a percentage of 2.10 +/- 0.02% of the injected dose per gram of tissue (%ID/g) at 2 hours after injection, versus an accumulation of 0.81 +/- 0.03%ID/g in the inflamed tissue. The tumor-to-contralateral muscle tissue ratio of (99m)Tc-DTPA-DG was 5.01 +/- 1.02, while the inflamed tissue-to-contralateral muscle tissue ratio was 1.2 +/- 0.08. Gamma-camera imaging revealed the tumor tissue at 2 hours after injection of (99m)Tc-DTPA-DG. The tumor-to-background ratio of (99m)Tc-DTPA-DG (3.8 +/- 0.95) at 2 hours was significantly (p < 0.05) higher in mammary tumor-bearing mice than was the inflamed tissue-to-background ratio (1.2 +/- 0.62) in the mice with inflammation.

(99m)Tc-DTPA-DG showed excellent tumor targeting and has promise as an imaging agent for clinical tumor targeting.