^(18)F-FDG PET-CT在结肠直肠癌术后CEA增高患者中的应用

^(18)F-FDG PET-CT detection for recurrence in postoperative colorectal cancer with unexplained rising carcinoembryonic antigen

目的评价18F-FDG PET-CT在查找结肠直肠癌术后CEA再次增高患者可能复发转移的应用价值。方法回顾性分析了47例结肠直肠癌术后患者,所有患者均术前肿瘤标志物CEA升高,术后有/无放、化疗,治疗后肿瘤标志物CEA降至正常范围,后临床随访中再次出现CEA增高,临床怀疑复发转移,行18F-FDG PET-CT全身扫描查找复发转移灶。结果 47例结肠直肠癌术后CEA升高患者中,PET-CT发现40例患者有异常代谢增高灶,7例全身未发现异常代谢增高灶。经再次手术、病理和/或1年以上的临床随诊,证实42例患者有肿瘤复发转移,5例无肿瘤复发转移。PET-CT对复发转移诊断的敏感性为92.3%、准确性为85.1%、阳性预测值为90.0%。血清CEA≥10 ng/m l的患者31例,复发转移的检出率为83.9%;血清CEA<10 ng/m l的患者16例,复发转移的检出率为62.5%。不同CEA升高水平,PET-CT对复发转移的检出率差异无统计学意义(P>0.05)。结论对于结肠直肠癌术后患者CEA水平增高,18F-FDG PET-CT检查是检出和定位复发病灶的有效方法。

Objective To explore the value of is F-FDG PET-CT scans in colorectal cancer （CRC） patients with clinically and/or radiologically suspicious tumor recurrence with unexplained rising carcinoembryonic antigen （CEA）. Methods PET-CT images of CRC patients were retrospectively reviewed. Only patients with unexplained rising CEA and suspected tumor recurrence were enrolled for further analysis. Results Forty-seven patients met the inclusion criteria. PET-CT finding was positive in 40 patients and not positive in 7 patients. The PET-CT images were compared with patho- logic findings （n = 16） and 1-year radiological and clinical follow-up （n =47）. Overall, the sensitivity of PET-CT was 92. 3%, the accuracy was 85.1%, and the positive predictive value was 90.0%. The recurrent disease was correctly identified by PET-CT in 18 of 21 patients with CEA≥ 20 ng/ml （ 85.7% ）, 26 of 31 patients with CEA ≥ 10 ng/ml （ 83.9% ）, and 10 of 16 patients with CEA 〈 10ng/ml （62. 5% ）. The accuracy of PET-CT was not significantly different among patients with different levels of abnormal CEA （P 〉 0.05）. Conclusion 18 F-FDG PET-CT is a potentially helpful roadmap for accurately locating and determining the postoperative recurrence of CRC with unexplained rising CEA.