Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota, USA.
Department of Neurosurgery, McGill University Health Centre, Montreal, Quebec, Canada.
World Neurosurg. 2020 Sep;141:e490-e497. doi: 10.1016/j.wneu.2020.05.228. Epub 2020 May 31.
The diagnosis of peripheral neurolymphomatosis (NL) is difficult and often delayed, because patients can have isolated, nonspecific nerve symptoms. Magnetic resonance imaging will usually show nonspecific findings of enlarged, contrast-enhancing nerves. We aimed to elucidate the mechanism behind an imaging finding we believe is pathognomonic of NL and likely of other hematologic diseases with peripheral nerve involvement.
We reviewed the imaging studies of a previously reported cohort of patients, in addition to those from more recent patients, all with tumefactive NL, in which enlarged nerve bundles were surrounded by tumor. We reviewed the demographic data, clinical data (e.g., primary or secondary disease, biopsy-proven diagnosis), and imaging findings (e.g., tumefactive appearance, primary involved nerve, location of epicenter of tumefactive appearance, vascular involvement).
All cases showed a maximum tumefactive appearance at branch or junction points, with a gradual decrease of this appearance moving proximally and distally from the epicenter in a "crescendo-decrescendo" pattern. We have described this as a phasic mechanism with 3 phases: malignant cells fill the intraneural space; extrude at a weak spot of the nerve, which often occurs at a branch or junction point; and then expand and fill the subparaneurial space, creating the grossly tumefactive appearance with proximal and distal spread.
We have presented a novel, unifying theory explaining the pathognomonic tumefactive appearance of NL. Our theory offers the first rational explanation for the radiological appearance of NL with peripheral nerve involvement. We believe that with earlier recognition of NL on imaging studies, patients will be able to receive an earlier diagnosis and undergo earlier treatment.
周围神经淋巴瘤病（NL）的诊断困难且常常延迟，因为患者可能有孤立的、非特异性的神经症状。磁共振成像通常会显示出非特异性的增大、增强的神经表现。我们旨在阐明我们认为是 NL 特有且可能是其他伴有周围神经受累的血液疾病的影像学表现背后的机制。
我们回顾了之前报道的一组患者的影像学研究，以及最近更多患者的影像学研究，这些患者均为肿块样 NL，其中增大的神经束被肿瘤包围。我们回顾了人口统计学数据、临床数据（例如，原发性或继发性疾病、经活检证实的诊断）和影像学发现（例如，肿块样外观、受累的主要神经、肿块样外观的中心位置、血管受累情况）。
所有病例均表现为分支或交界处的最大肿块样外观，从中心向近端和远端逐渐减小，呈“渐强-渐弱”模式。我们将这种现象描述为一种阶段性机制，具有 3 个阶段：恶性细胞充满神经内间隙；在神经的薄弱点挤出，这通常发生在分支或交界处；然后扩展并充满神经旁间隙，形成大体肿块样外观，并向近端和远端扩散。
我们提出了一种新颖的、统一的理论，解释了 NL 特有的肿块样外观。我们的理论为伴有周围神经受累的 NL 的影像学表现提供了第一个合理的解释。我们相信，通过更早地在影像学研究中识别 NL，患者将能够更早地得到诊断并接受治疗。
