Inner radiotherapy using radionuclide has been used more and more in clinic

and it is important to predict and enhance its therapeutic effect. In this study

99mTc-HL91 imaging was performed in mice bearing S180 tumor before P-colloid interstitial treatment and some of mice inhaled carbogen gas as a method to solve hypoxia of tumor 32 tissue. Although 99m Tc-HL91 retention in tumor was decrease significantly after carbogen breathing

and tumor mass was less in the carbogen-breathing mice than in the air-breathing mice

99m Tc-HL91 retention was not related to tumor mass after P-colloid interstitial treatment

which implied that carbogen breathing could improve therapeutic effect of 32 32P-colloid interstitial treatment

and 99m Tc-HL91 imaging was useful to detect effect of hypoxia intervention but was unable to predict therapeutic effect of P-colloid interstitial treatment. 32