Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany.
Department of Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
Semin Nucl Med. 2022 Sep;52(5):611-618. doi: 10.1053/j.semnuclmed.2022.01.003. Epub 2022 Mar 5.
PET/MRI has been available since 2010, representing the newest of the hybrid imaging modalities. It combines functional as well as morphologic high-resolution MRI data with metabolic information from PET, providing image data sets with complementary information. Especially in the field of oncology, PET/MRI is a promising imaging modality with diverse applications. Since its introduction there has already been a large quantity of studies indicating a high diagnostic value of PET/MRI for whole-body cancer staging. The simultaneous acquisition of metabolic PET and MRI data is expected to have a major impact in the assessment of breast cancer due to the superior resolution of MRI in breast tissue compared to CT. While there is an ongoing debate if the added value of breast F-FDG PET/MRI in the primary diagnosis of breast cancer has clinical impact compared to breast MRI, a large number of studies have proven that F-FDG PET/MRI is extremely valuable for whole-body breast cancer staging and especially for treatment monitoring. Besides molecular markers, distant metastases and axillary lymph node involvement are the most important predictors for overall survival and recurrence in breast cancer patients. Due to the high soft tissue contrast, functional imaging from MRI and metabolic information from PET, distant metastases in organs and in particular in the bones are detected better compared to the conventional staging algorithm with CT and bone scan and can significantly influence the therapy regime. Instead of mastectomy and extensive axillary dissection being performed in many patients, the improved imaging and diagnostic confidence also has helped that local therapy control can be achieved with reduced invasiveness. A future role of F-FDG PET/MRI could therefore become treatment response evaluation under neoadjuvant treatment before or instead of operative therapy. In addition to reduced radiation exposure compared to conventional staging examinations, hybrid F-FDG PET/MRI might serve as a comprehensive "all-in-one" breast cancer staging tool, providing precise local and whole-body staging including MRI of the head in one procedure, which save patients a diagnostic marathon.
正电子发射断层扫描/磁共振成像（PET/MRI）自 2010 年以来已经可用，是最新的混合成像方式之一。它将功能和形态高分辨率 MRI 数据与来自 PET 的代谢信息相结合，提供具有互补信息的图像数据集。特别是在肿瘤学领域，PET/MRI 是一种具有广泛应用前景的成像方式。自推出以来，已经有大量研究表明，PET/MRI 对全身癌症分期具有很高的诊断价值。由于 MRI 在乳腺组织中的分辨率优于 CT，因此同时采集代谢 PET 和 MRI 数据有望在乳腺癌评估中产生重大影响。虽然关于在乳腺癌的初始诊断中，乳腺 F-FDG PET/MRI 的附加价值是否具有临床影响仍存在争议，但大量研究已经证明，F-FDG PET/MRI 对于全身乳腺癌分期，尤其是治疗监测非常有价值。除了分子标志物外，远处转移和腋窝淋巴结受累是乳腺癌患者总生存和复发的最重要预测因素。由于 MRI 的软组织对比度高，功能成像和 PET 的代谢信息，与 CT 和骨扫描的常规分期算法相比，能够更好地检测到远处转移，特别是在骨骼中，并且可以显著影响治疗方案。在许多患者中，不再进行乳房切除术和广泛的腋窝清扫术，而是通过改善成像和诊断信心，也有助于通过减少侵袭性来实现局部治疗控制。因此，F-FDG PET/MRI 的未来作用可能成为新辅助治疗前后（而非手术治疗）的治疗反应评估。与传统分期检查相比，混合 F-FDG PET/MRI 还可以作为一种综合的“一站式”乳腺癌分期工具，在一次程序中提供包括头部 MRI 的精确局部和全身分期，为患者节省了诊断马拉松。
