Abstract

In order to evaluate the value of 99Tcm–MIBI uptake in the diagnosis, prediction of pathologic type, tumor stage and size, 22 cases with primary lung cancer (PLC) were enrolled to the study, in a prospective manner. Anterior and posterior planar images were taken 15 minutes after injection of 555-740 MBq 99Tcm–MIBI intravenously and visual evaluation was done foremost. Then region of interest (ROI) was drawn over the tumor (T) and contra-lateral normal lung area (NL) in each position and mean average counts per pixel were obtained from which 99Tcm–MIBI tumor-to-normal lung uptake (T/NL) ratios were calculated and semi-quantitative analysis were done.

The sensitivity of planar 99Tcm–MIBI in detection of PLC was 95% (21/22). Mean age of these 21 cases that showed MIBI uptake was 64±7 (50-74) years and all of them were male. Mean T/NL ratio of cases who were included in semi-quantitative analysis was 1.45±0.32 (1.08-2.22). According to tumor type, T/NL of SCLC (n=5) was significantly higher than NSCLC (n=15) (1.740.44 vs 1.350.21, p<0.05). There was a good positive correlation between the tumor size and T/NL ratio (r=0.546, p<0.05). With increasing the tumor size, T/NL was increased. We could not found any relationship between the TNM stage of tumor and T/NL ratios.

In conclusion, according to this preliminary study, we suggest that chest imaging using 99Tcm–MIBI may be a useful method for the detection of PLC and may give some clue about the size and type of the tumor. We think it has sufficient worth for further studies.