目的:神经肌肉性脉络膜瘤(NMC)是一种罕见的周围神经发育畸形,通常与纤维瘤样纤维瘤病(DTF)的发展有关。NMC和NMC-DTF通常都含有致病性CTNNB1突变,NMC-DTF仅在受NMC影响的神经区域内发展。作者旨在确定是否存在神经驱动机制参与从潜在的受NMC影响的神经形成NMC-DTF。
方法:对在作者机构评估的坐骨神经(或腰骶丛)诊断为NMC-DTF的患者进行回顾性回顾。回顾了MRI和FDGPET/CT研究,以确定沿坐骨神经的NMC和DTF病变的具体关系和构型。
结果:10例患者的坐骨神经NMC和NMC-DTF累及腰骶丛,坐骨神经,或坐骨神经分支。所有原发性NMC-DTF病变均位于坐骨神经区域。8例NMC-DTF显示坐骨神经环状包裹,一个紧靠坐骨神经。一名患者有远离坐骨神经的原发性DTF,但随后在NMC神经区域内发展了多灶性DTF,包括2个围绕着母体神经的卫星DTF。五名患者共有8个卫星DTF,其中4个邻接母神经,3个周向涉及母神经。
结论:根据临床和放射学数据,提出了由受NMC影响的神经节段支配的软组织产生NMC-DTF的新机制,反映了他们共同的分子遗传改变。作者认为,DTF以径向方式从NMC向外发展,或者在NMC中出现并随着其生长而缠绕。在任何一种情况下,NMC-DTF直接从神经产生,可能来自NMC基质微环境中的(myo)成纤维细胞,并向外生长到周围的软组织中。根据提出的发病机制,提出了对患者诊断和治疗的临床意义。
OBJECTIVE: Neuromuscular choristoma (NMC) is a rare developmental malformation of peripheral nerve that is frequently associated with the development of a desmoid-type fibromatosis (DTF). Both NMC and NMC-DTF typically contain pathogenic CTNNB1 mutations and NMC-DTF develop only within the NMC-affected nerve territory. The authors aimed to determine if there is a nerve-driven mechanism involved in the formation of NMC-DTF from the underlying NMC-affected nerve.
METHODS: Retrospective review was performed for patients evaluated in the authors\' institution with a diagnosis of NMC-DTF in the sciatic nerve (or lumbosacral plexus). MRI and FDG PET/CT studies were reviewed to determine the specific relationship and configuration of NMC and DTF lesions along the sciatic nerve.
RESULTS: Ten patients were identified with sciatic nerve NMC and NMC-DTF involving the lumbosacral plexus, sciatic nerve, or sciatic nerve branches. All primary NMC-DTF lesions were located in the sciatic nerve territory. Eight cases of NMC-DTF demonstrated circumferential encasement of the sciatic nerve, and one abutted the sciatic nerve. One patient had a primary DTF remote from the sciatic nerve, but subsequently developed multifocal DTF within the NMC nerve territory, including 2 satellite DTFs that circumferentially encased the parent nerve. Five patients had a total of 8 satellite DTFs, 4 of which abutted the parent nerve and 3 that circumferentially involved the parent nerve.
CONCLUSIONS: Based on clinical and radiological data, a novel mechanism of NMC-DTF development from soft tissues innervated by NMC-affected nerve segments is proposed, reflecting their shared molecular genetic alteration. The authors believe the DTF develops outward from the NMC in a radial fashion or it arises in the NMC and wraps around it as it grows. In either scenario, NMC-DTF develops directly from the nerve, likely arising from (myo)fibroblasts within the stromal microenvironment of the NMC and grows outward into the surrounding soft tissues. Clinical implications for patient diagnosis and treatment are presented based on the proposed pathogenetic mechanism.