99mTc-gluconate three-phase imaging for diagnosis of lung cancer

99mTc-gluconate lung imagings were performed in 121 cases which included 55 of lung cancers, 49 of benign lesions and 17 of normal controls. In 78 cases of them, three-phase lung imaging was performed and the uptake ratio (UR) and cancer index (LCI) were calculated. Using the values higher than the mean UR + 2SD in healthy persons as a criterion of positive uptake, the percentages of postive uptake in lung cancers and in benign lesions were 98.2% and 61.2% respectively. The difference between them was statistically significant (P<0.01). There was no positive uptake in the normal group. Using LCI as a parameter for the differentiation of the nature of lung lesions, the sensitivity was 86.8%, the specificity 95.7% and the accuracy 90.2% for diagnosis of lung cancer. These results show 99mTc-gluconate three-phase lung imaging is a valuable detecting method for patients with suspected lung cancer