正电子发射断层显像-计算机断层显像在鼻咽癌远处转移诊断中的应用价值

The role of PET-CT in diagnosing distant metastasis of nasopharyngeal carcinoma

目的探讨正电子发射断层显像-计算机断层显像（PET—CT）在鼻咽癌远处转移诊断和M分期中的价值。方法257例初治鼻咽癌患者于治疗前行胸部X线摄片、腹部B型超声检查、骨发射单光子计算机断层扫描（ECT）等常规检查和PET—CT扫描。依据病理活检和随访结果比较PET—CT和常规检查在远处转移诊断和M分期中的作用。结果39例（15．2％）鼻咽癌存在远处转移，其中PET-CT检出34例，而常规检查仅检出22例。PET—CT假阳性率为12．8％（5／39）。若按转移灶分布部位分析，PET-CT能提高纵隔转移检出率（X^2=4．063，P=0．041）和骨转移的检出率（X^2=5．939，P=0．015）。与常规检查相比，PET-CT改变了19例（7．4％）患者的M分期，判断正确14例，判断错误5例。结论PET-CT判断鼻咽癌远处转移和M分期较常规检查准确。

Objective To explore the clinical significance of PET-CT in evaluating distant metastasis and M staging of nasopharyngeal carcinoma（NPC）. Methods 257 NPC patients with no prior treatment were investigated with PET-CT and conventional imaging （chest X-ray, abdominal ultrasound, and bone scan）. The findings of PET-CT in diagnosing distant metastasis and M staging were compared with those of conventional imaging aeeordirig to the results of biopsy and follow-up. Results PET-CT disclosed 34 of 39 patients with distant malignancy compared with 22 patients disclosed by conventional imaging. The false positive rate of PET-CT was 12.8 %. On region-based analyses, PET-CT was more effective than bone scan and chest X-ray for detecting mediastinum metastasis （X2=4.063, P =0.041） and bone metastasis （X2=5.939, P=0.015）, respectively. Compared with conventional imaging, PET-CT had an impact on the M staging of 19 patients （7.4 %）, of which 15 patients were truly staged and 4 patients incorrectly staged. Conclusion PET-CT is superior to MRI in evaluating distant metastasis and M staging of NPC.