J Nucl Med:PET/CT比常规成像更能准确诊断乳腺癌

　　发表在《核医学杂志》1月刊上的研究显示，18F-氟代脱氧葡萄糖(18F-FDG)正电子成像术(PET)/计算机断层扫描(CT)可为处在初始阶段的局部晚期乳腺癌患者提供重要的预后分层信息。与传统成像术相比，18F-FDG PET/CT可一次性完整而精确地发现位于胸部、腹部和骨骼内的病变组织，研究中这种方式使超过50%的患者改变了疾病治疗方案。

　　美国国家综合癌症网(NCCN)指南建议通过体检、双边乳房x光检查、超声波扫描术或乳腺磁共振成像等对乳腺进行检查，此外还要进行胸部CT诊断、腹部或骨盆CT诊断或磁共振成像、骨扫描等来对乳腺肿瘤周围较远部位进行检测来判断其是否发生转移。NCCN指南认为，当常规检测出现模棱两可或可疑的情况时，18F-FDG PET/CT就可帮到大忙。

　　首席研究员David Groheux博士介绍称：“患有局部晚期乳腺癌的患者，其预后往往不理想。研究中，我们的目的是评估18F-FDG PET/CT在初始阶段能否对这些患者的预后分层和疾病控制产生影响。”

　　在这项为期5年的研究中，共117名患有局部晚期乳腺癌的患者参与其中。这些患者开始先接受了常规的成像方式，包括骨扫描、胸部X光照射、专用CT、腹骨盆超声波或强化CT检测，并依据检测结果来对病情进行分期。然后，他们又接受了18F-FDG PET/CT扫描，扫描结果由和医学专家进行审核，而这些专家并不知道之前的常规监测结果。最后研究人员把两种方式的成像结果进行了对比。

　　结果显示，所有原发性肿瘤通过18F-FDG PET/CT都被检测出来。扫描还在患有三期癌症的患者中检测出淋巴结转移，在32名患者中发现可疑的的淋巴结转移。此外，18F-FDG PET/CT还在43名患者中发现癌症向远处转移，包括骨骼、远处淋巴结、肝部、肺部以及胸膜等，而常规成像方式只能在28名患者中检测出癌症向远处转移。总体来看，18F-FDG PET/CT扫描使117名患者中的61名改变了之前的疾病分期，这样反过来会影响相应的治疗方式。

　　Groheux博士称：“这种分子成像有助于研究人员研发出个性化的治疗药物，为真正意义上的定制治疗方案提供足够的依据。基于这些发现，18F-FDG PET/CT对于局部晚期乳腺癌患者来说或许是唯一最好的远距离分期模式。”

¹⁸F-FDG PET/CT in Staging Patients with Locally Advanced or Inflammatory Breast Cancer: Comparison to Conventional Staging 

The prognosis of patients with locally advanced breast cancer (LABC) remains poor. We prospectively investigated the impact of ¹⁸F-FDG PET/CT at initial staging in this clinical setting and compared PET/CT performance with that of conventional distant work-up. 

Methods: During 60 mo, consecutive patients with LABC (clinical T4 or N2–N3 disease) underwent ¹⁸F-FDG PET/CT. The yield was assessed in the whole group and separately for noninflammatory and inflammatory cancer. The performance of PET/CT was compared with that of a conventional staging approach including bone scanning, chest radiography, or dedicated CT and abdominopelvic sonography or contrast-enhanced CT.

Results: 117 patients with inflammatory (n = 35) or noninflammatory (n = 82) LABC were included. ¹⁸F-FDG PET/CT confirmed N3 nodal involvement in stage IIIC patients and revealed unsuspected N3 nodes (infraclavicular, supraclavicular, or internal mammary) in 32 additional patients. Distant metastases were visualized on PET/CT in 43 patients (46% of patients with inflammatory carcinoma and 33% of those with noninflammatory LABC). Overall, ¹⁸F-FDG PET/CT changed the clinical stage in 61 patients (52%). Unguided conventional imaging detected metastases in only 28 of the 43 patients classified M1 with PET/CT (65%). ¹⁸F-FDG PET/CT outperformed conventional imaging for bone metastases, distant lymph nodes, and liver metastases, whereas CT was more sensitive for lung metastases. The accuracy in diagnosing bone lesions was 89.7% for planar bone scanning versus 98.3% for ¹⁸F-FDG PET/CT. The accuracy in diagnosing lung metastases was 98.3% for dedicated CT versus 97.4% for ¹⁸F-FDG PET/CT. 

Conclusion: ¹⁸F-FDG PET/CT had the advantage of allowing chest, abdomen and bone to be examined in a single session. Almost all distant lesions detected by conventional imaging were depicted with PET/CT, which also showed additional lesions.