Visualization of lung cancer with 99Tcm-tetrofosmin imaging: a comparison with 201T1

We evaluated the usefulness of 99Tcm-tetrofosmin imaging in lung cancer. The study sample comprised 46 patients with lung cancer. Single photon emission tomography was conducted after the intravenous injection of 740 MBq 99Tcm-tetrofosmin and 111 MBq 201T1-chloride. We obtained an uptake ratio (counts per pixel in the lesion/counts per pixel in contralateral normal lung) for each scan to evaluate the degree of uptake in the tumour. Our results demonstrate that 89.1% of the primary lung cancers were visualized by 99Tcm-tetrofosmin and 95.7% by 201T1. The difference between the 201T1 uptake ratio and the 99Tcm-tetrofosmin uptake ratio was significantly greater in squamous cell carcinomas than small cell carcinomas (P < 0.01) and tended to be greater in squamous cell carcinomas than adenocarcinomas (P = 0.093). This study has indicated that 99Tcm-tetrofosmin, like 201T1, is a highly effective agent in the delineation of lung cancer. The difference between the 99Tcm-tetrofosmin and 201T1 uptake ratios might provide further information regarding the histological type of lung cancer.