Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore.
Department of Neuroradiology, National Neuroscience Institute, Singapore, Singapore.
Neuroradiology. 2020 Jun;62(6):669-676. doi: 10.1007/s00234-020-02377-0. Epub 2020 Feb 20.
Primary central nervous system lymphoma (PCNSL) presenting with atypical radiological findings often leads to delayed diagnosis. We aim to characterize the radiological features and apparent diffusion coefficient (ADC) values of PCNSL with atypical neuroimaging presentation in our local population.
We retrospectively reviewed all patients with histological diagnosis of CNS lymphoma at our tertiary center from 2005 to 2016. We screened all initial pre-treatment MRIs and excluded cases with typical imaging findings of contrast-enhancing lesions without intra-lesional susceptibility and central non-enhancement. Additional exclusion criteria included (i) relapsed PCNSL, (ii) secondary CNS lymphoma, and (iii) positive HIV status. Two independent raters scored MRI and CT scans at presentation. We computed ADC values in the tumors by 2 methods: single region of interest (ROI1) and multiple ROI (ROI2).
Sixteen (25.4%) of 63 patients with CNS lymphoma met inclusion criteria. There were 8 men; median age was 61 (range 22-81) years. Histological diagnoses were diffuse large B cell lymphoma (n = 14) and intravascular lymphoma (n = 2). Fifteen (93%) patients had enhancing lesions (5 solitary; 10 multifocal); most enhancing lesions had T1 hypointense (67%) and T2 mixed (53%) signals, and 6 (40%) had central non-enhancing regions. Nine (56%) patients had lesions with susceptibility. Using the ROI methods, median values for minimum ADC and mean ADC ranged 0.65-0.71 × 10 mm/s and 0.79-0.84 × 10 mm/s respectively.
PCNSL with atypical radiological features represented one-fourth of our histologically diagnosed lymphoma cases; low ADC values in atypical lesions should prompt clinicians to consider early biopsy for definitive diagnosis.
原发中枢神经系统淋巴瘤（PCNSL）表现出不典型的影像学表现常导致诊断延迟。我们旨在描述我们当地人群中具有不典型神经影像学表现的 PCNSL 的影像学特征和表观扩散系数（ADC）值。
我们回顾性分析了 2005 年至 2016 年在我们的三级中心接受组织学诊断为中枢神经系统淋巴瘤的所有患者。我们筛选了所有初始治疗前的 MRI，并排除了具有无瘤内敏感性和中央非增强的增强病变的典型影像学表现的病例。其他排除标准包括（i）复发性 PCNSL，（ii）继发性 CNS 淋巴瘤，和（iii）HIV 阳性。两名独立的评估者对初始 MRI 和 CT 扫描进行评分。我们通过 2 种方法计算肿瘤的 ADC 值：单个感兴趣区域（ROI1）和多个 ROI（ROI2）。
63 例 CNS 淋巴瘤患者中，有 16 例（25.4%）符合纳入标准。其中 8 例为男性；中位年龄为 61 岁（范围 22-81 岁）。组织学诊断为弥漫性大 B 细胞淋巴瘤（n=14）和血管内淋巴瘤（n=2）。15 例（93%）患者有增强病变（5 例为单发，10 例为多发）；大多数增强病变的 T1 信号为低信号（67%），T2 信号混杂（53%），6 例（40%）有中央非增强区。9 例（56%）患者的病变有敏感性。使用 ROI 方法，最小 ADC 和平均 ADC 的中位数范围分别为 0.65-0.71×10mm/s 和 0.79-0.84×10mm/s。
具有不典型影像学特征的 PCNSL 占我们组织学诊断淋巴瘤病例的四分之一；不典型病变的低 ADC 值应促使临床医生考虑早期活检以明确诊断。
