Abstract：
Neuromuscular choristoma (NMC) is a rare peripheral nerve lesion characterized by abnormal presence of muscle within nerve. Associated desmoid-type fibromatosis (NMC-DTF) often develops. We report 18F-fluorodeoxyglucose positron emission tomography (FDG PET) characteristics of NMC and NMC-DTF and propose that increased FDG activity within NMCs may be associated with subclinical NMC-DTF or NMC-DTF \"precursor\" tissue.
Our institutional database was searched for all NMC cases. Inclusion criteria were 1) confirmed diagnosis of NMC with or without biopsy, and 2) available PET and MRI studies. PET data included SUVmax and SUVmean of NMCs, contralateral limb normal skeletal muscle and unaffected nerves, and SUVmax of NMC-DTF if present. SUV values were compared using paired t-test. A p value of < 0.05 was considered statistically significant.
Our cohort consisted of 9 patients with NMC, 8 cases involving sciatic nerve and 1 of brachial plexus. On PET imaging, all NMC-affected nerve segments showed significantly higher FDG uptake (SUVmax/mean) compared to both contralateral normal nerve and normal skeletal muscle (all P < 0.05). Similar to sporadic DTF, NMC-DTF was highly FDG-avid (average SUVmax of 4.2). SUVmax in NMC with or without concurrent NMC-DTF did not differ (p = 0.76). Within NMC-affected nerve segment, FDG activity was relatively higher in areas with low T1/T2 MR signal.
All NMCs were more FDG avid compared to both normal skeletal muscle and contralateral unaffected nerve, arguing against the presence of heterotopic muscle in NMC as the source of FDG avidity. FDG avidity within NMC may reflect subclinical NMC-DTF or a precursor lesion, as NMC-DTF are highly FDG-avid, and the highest regions of FDG avidity in NMC occurred in regions with MR characteristics associated with NMC-DTF (i.e., lower T1/T2 signal). We believe that the integration of FDG PET with serial MR imaging in patient follow up will clarify its utility in both detection and surveillance of NMC-DTF.
Our institutional database was searched for all NMC cases. Inclusion criteria were 1) confirmed diagnosis of NMC with or without biopsy, and 2) available PET and MRI studies. PET data included SUVmax and SUVmean of NMCs, contralateral limb normal skeletal muscle and unaffected nerves, and SUVmax of NMC-DTF if present. SUV values were compared using paired t-test. A p value of < 0.05 was considered statistically significant.
Our cohort consisted of 9 patients with NMC, 8 cases involving sciatic nerve and 1 of brachial plexus. On PET imaging, all NMC-affected nerve segments showed significantly higher FDG uptake (SUVmax/mean) compared to both contralateral normal nerve and normal skeletal muscle (all P < 0.05). Similar to sporadic DTF, NMC-DTF was highly FDG-avid (average SUVmax of 4.2). SUVmax in NMC with or without concurrent NMC-DTF did not differ (p = 0.76). Within NMC-affected nerve segment, FDG activity was relatively higher in areas with low T1/T2 MR signal.
All NMCs were more FDG avid compared to both normal skeletal muscle and contralateral unaffected nerve, arguing against the presence of heterotopic muscle in NMC as the source of FDG avidity. FDG avidity within NMC may reflect subclinical NMC-DTF or a precursor lesion, as NMC-DTF are highly FDG-avid, and the highest regions of FDG avidity in NMC occurred in regions with MR characteristics associated with NMC-DTF (i.e., lower T1/T2 signal). We believe that the integration of FDG PET with serial MR imaging in patient follow up will clarify its utility in both detection and surveillance of NMC-DTF.
摘要：
背景：神经肌肉性脉络膜瘤（NMC）是一种罕见的周围神经病变，其特征是神经内肌肉的异常存在。相关的纤维瘤病（NMC-DTF）经常发生。我们报告了NMC和NMC-DTF的18F-氟代脱氧葡萄糖正电子发射断层扫描（FDGPET）特征，并提出NMC中FDG活性的增加可能与亚临床NMC-DTF或NMC-DTF“前体”组织有关。
方法：我们的机构数据库搜索了所有NMC病例。纳入标准为1）确诊的NMC有或没有活检，和2）可用的PET和MRI研究。PET数据包括NMC的SUVmax和SUVmean，对侧肢体正常骨骼肌和未受影响的神经，以及NMC-DTF的SUVmax(如果存在)。使用配对t检验比较SUV值。<0.05的p值被认为是统计学上显著的。
结果：我们的队列包括9例NMC患者，累及坐骨神经8例，臂丛1例。在PET成像上,与对侧正常神经和正常骨骼肌相比，所有受NMC影响的神经节段均显示出更高的FDG摄取（SUVmax/平均值）（均P<0.05）。类似于零星的DTF，NMC-DTF是高度FDG-嗜好的(平均SUVmax为4.2)。有或没有并发NMC-DTF的NMC中的SUVmax没有差异(p=0.76)。在受NMC影响的神经段内，在T1/T2MR信号较低的区域，FDG活性相对较高。
结论：与正常骨骼肌和对侧未受影响的神经相比，所有NMC都更喜欢FDG，反对NMC中异位肌作为FDG代谢的来源。NMC内的FDG摄取可能反映了亚临床NMC-DTF或前病变，由于NMC-DTF是高度FDG-狂热的，NMC中FDG亲和力的最高区域发生在与NMC-DTF相关的MR特征区域(即，较低的T1/T2信号)。我们相信，在患者随访中，将FDGPET与系列MR成像相结合将阐明其在NMC-DTF的检测和监测中的实用性。
方法：我们的机构数据库搜索了所有NMC病例。纳入标准为1）确诊的NMC有或没有活检，和2）可用的PET和MRI研究。PET数据包括NMC的SUVmax和SUVmean，对侧肢体正常骨骼肌和未受影响的神经，以及NMC-DTF的SUVmax(如果存在)。使用配对t检验比较SUV值。<0.05的p值被认为是统计学上显著的。
结果：我们的队列包括9例NMC患者，累及坐骨神经8例，臂丛1例。在PET成像上,与对侧正常神经和正常骨骼肌相比，所有受NMC影响的神经节段均显示出更高的FDG摄取（SUVmax/平均值）（均P<0.05）。类似于零星的DTF，NMC-DTF是高度FDG-嗜好的(平均SUVmax为4.2)。有或没有并发NMC-DTF的NMC中的SUVmax没有差异(p=0.76)。在受NMC影响的神经段内，在T1/T2MR信号较低的区域，FDG活性相对较高。
结论：与正常骨骼肌和对侧未受影响的神经相比，所有NMC都更喜欢FDG，反对NMC中异位肌作为FDG代谢的来源。NMC内的FDG摄取可能反映了亚临床NMC-DTF或前病变，由于NMC-DTF是高度FDG-狂热的，NMC中FDG亲和力的最高区域发生在与NMC-DTF相关的MR特征区域(即，较低的T1/T2信号)。我们相信，在患者随访中，将FDGPET与系列MR成像相结合将阐明其在NMC-DTF的检测和监测中的实用性。
