Emmering Jasper, Vogel Wouter V, Stokkel Marcel P M
Department of Nuclear medicine, The Netherlands Cancer Institute, Antoni van Leeuwenhoek hospital (NKI-AVL), Amsterdam, The Netherlands.
Nucl Med Commun. 2012 Feb;33(2):117-20. doi: 10.1097/MNM.0b013e32834e3ad0.
Intramuscular metastases (IM) are both rare and difficult to detect using routine anatomical computed tomography (CT) imaging. However, since the introduction of 18F-fluoro-deoxy-glucose (FDG) PET-CT, the number of detected IM has increased. We review the available literature to illustrate the relevance of these findings for staging and patient management.
In a review of the literature, we found one series and 33 case reports of IM shown on FDG PET-CT. No cases were reported before 2005. Furthermore, we present a patient with nonsmall cell lung cancer and a solitary distant metastasis in the left musculus infraspinatus that was not detected on diagnostic CT, but was found on FDG PET-CT.
For a total of 39 recorded cases of IM, we found that FDG PET-CT had a significant impact on patient management in at least 51% of cases. Where reported, lesions were either isodense or hypodense on CT compared with the surrounding muscle tissue. The lesions that were also analyzed with MRI showed heterogeneous intensity. Five out of 39 patients had metastases in the extraocular muscles of one or both orbits.
FDG PET-CT appears to be a sensitive tool for detecting IM, with important impact on management in many cases.
肌肉内转移瘤（IM）既罕见，又难以通过常规解剖计算机断层扫描（CT）成像检测到。然而，自18F-氟脱氧葡萄糖（FDG）PET-CT问世以来，检测到的IM数量有所增加。我们回顾现有文献，以阐明这些发现对分期和患者管理的相关性。
在文献回顾中，我们发现了一组病例系列以及33例FDG PET-CT显示的IM病例报告。2005年之前未见病例报告。此外，我们还介绍了一名非小细胞肺癌患者，其左冈下肌有一个孤立的远处转移灶，诊断性CT未检测到，但FDG PET-CT发现了该转移灶。
在总共39例记录的IM病例中，我们发现FDG PET-CT在至少51%的病例中对患者管理有显著影响。报告显示，与周围肌肉组织相比，CT上的病变要么等密度，要么低密度。经MRI分析的病变显示强度不均匀。39例患者中有5例在一个或两个眼眶的眼外肌中有转移灶。
FDG PET-CT似乎是检测IM的敏感工具，在许多情况下对管理有重要影响。
