^99mTc—HL91 SPECT乏氧显像与非小细胞肺癌预后的关系

Prognostic value of ^99mTc-HL91 SPECT hypoxia imaging in patients with advanced NSCLC

目的利用^99mTc—HL91 SPECT乏氧显像，研究非小细胞肺癌（NSCLC）放疗中乏氧程度及乏氧变化与预后的关系。方法32例NSCLC患者，三维适形放射治疗前1～2d行^99mTc—HL91 SPECT检查，其中18例分别于放疗过程中接受30～40Gy照射，放疗后1～2d行^99mTc—HL91 SPECT检查。利用感兴趣区（ROI）技术，计算靶与非靶的比值。治疗结束后，所有患者进行随访，分析放疗前及放疗中T与N比值的变化与放疗疗效及生存率的相关性。结果放疗中，T与N的比值逐渐下降（P=0．000）。放疗前，T与N比值较低组的有效率（P=0．002）和生存率均高于T与N比值较高组（P=0．043）。放疗前后，T与N比值变化较大组的放疗有效率与生存率高于变化较小组，差异无统计学意义。结论HL91 SPECT显像对NSCLC患者的预后有一定的预测价值。

Objective Tumor hypoxia can influence response to radiotherapy and other treatment medalities. Oxygenation status is proved to be an independent prognostic factor. ^99mTc-HL91 （^99mTc labeled 4,9-diaza-3,3,10,10-tetramethyldedecan-2, 11-dione dioxime） is a potential noninvasive marker of tumor hypoxia. It has been reported that 99mTc-HL91 has certain validity for hypoxia imaging. But its clinical study had not been reported widely. This study was carried out to evaluate the relationship between the T/N ratio of HL91 SPECT hypoxia imaging and the radiotherapeutic outcome. Methods 32 patients with pathologically proven non-small cell lung cancer received three-dimensional conformal radiotherapy were enrolled into the study. ^99mTc-HL91 SPECT scanning was performed in all patients at one or two days before radiotherapy. It was also performed in 18 patients at one or two days after the onset of radiotherapy, when they received a dose of 30 ～ 40 Gy already. Anterior, posterior and lateral planar images were collected at 2, 4 and 6 hours, respectively, after intravenous injection of approximately 740 MBq ^99mTc-HL91. Regions of interest （ROIs） were drawn in the tumor and the contralateral normal lung tissue, and the radioactivity ratio of tumor to normal tissue （T/N） was calculated. To assess whether the tumor uptake of ^99mTc-HL91 is predictive of treatment response, the SPECT results were correlated with the results of clinical follow-up. Results The relationship between T/N ratios at 4 h images after injection was shown to be the best of three acquired images before radiotherapy. The response and overall survival to radiotherapy were analyzed for all 32 patients. The results of ^99mTc-HL91 correlated well with radiotherapy response （ P = 0. 002 ） and also patients＇ survival （P =0.043）. The average T/N values of 18 patients who received serial scanning were 1.57 ± 0. 18,1.44 ± 0.19 and 1.30 ± 0.14, respectively. There was a significant difference between those three groups （ P = 0.000）. The T/N changes during radiotherapy were not associated with the treatment outcome. Conclusion HL91 SPECT imaging can identify the hypoxia status and changes during radiotherapy in lung cancer. Hypoxia SPECT imaging with HL91 before treatment may predict radiotherapy response and patients＇ survival. Longer follow up in more patients is planned to confirm this result.