The Study Of SPECT/CT ⁹⁹Tc^m-HL91 Hypoxia Imaging For Non-small Cell Lung Cancer Before And After Radiotherapy

Objective:To investigate the clinical value of ⁹⁹Tc^m-HL91 hypoxia imaging on detecting tumor hypoxia,predicting and evaluating the radiotherapy response for patients with non-small cell lung cancer(NSCLC).Methods:Thirty patients,15 cases adenocarcinomas,14 cases squamous cell carcinoma and one case large cell carcinoma were confirmed by pathology,;Planar imagings at 10min,1h,4h and fusion imagings at 4h in 30 cases were performed in one week before and after radiotherapy,respectively.Regions of interest(ROIs) were drawn in the tumor (T) and contralateral position(NT) and the radioactivity ratios of tumor to normal(T/NT) were calculated.The correlation between the T/NT value changes and the response to radiotherapy was analyzed.Results:â‘ The tumor hypoxic tissue was clearly visualed at 4h.Twenty-three cases were displayed by planar imagings,29 cases by tomographic imagings,and 30 cases by fusion imagings.There was a significant statistical difference among them(X²=9.34,P＜0.05).The positive rates of tomographic and fusion imaging was higher than that of planar imaging(P＞0.05).â‘¡The T/NT values at 4h by planar imaging and 4h by tomographic imaging were 1.61±0.14,1.77±0.16 respectively before radiotherapy,and they were 1.37±0.23,1.49±0.26 after radiotherapy.The T/NT values were all decreased after radiotherapy(P＜0.05).â‘¢The average T/NT values at 4h by tomographic imaging before radiotherapy was 1.77,which was regarded as threshold value.The T/NT values in 17 cases≥1.77,the therapeutic rate was 41.2%(7/17);The T/NT values in 13 cases＜1.77, the therapeutic rate was 84.6%(11/13).There was a significant statistical difference between them(P=0.02).â‘£Complete remission(CR) was achieved in no case,partial remission(PR) in 18 cases,no change(NC) in 9 cases,and progressive disease(PD) in 3 cases after radiotherapy.The decreased rates of T/NT values at 4h by tomographic imaging in the effective group(CR+PR) and ineffective group(NC+PD) were 0.24±0.07 and 0.07±0.06,with a significant statistical difference(t=7.82,P＜0.01).Conclution:⁹⁹Tc^m-HL91 SPECT/CT fusion imaging offers more valuable information with CT anatomy localization,and it is much better than planar imaging.