Morana Giovanni, Alves Cesar Augusto, Tortora Domenico, Finlay Jonathan L, Severino Mariasavina, Nozza Paolo, Ravegnani Marcello, Pavanello Marco, Milanaccio Claudia, Maghnie Mohamad, Rossi Andrea, Garrè Maria Luisa
Neuroradiology Unit, Istituto Giannina Gaslini, Genoa, Italy.
Radiology Department, Hospital Das Clinicas, Sao Paulo, Brazil.
Neuroradiology. 2018 Jan;60(1):89-99. doi: 10.1007/s00234-017-1947-3. Epub 2017 Nov 11.
The role of T2*-based MR imaging in intracranial germ cell tumors (GCTs) has not been fully elucidated. The aim of this study was to evaluate the susceptibility-weighted imaging (SWI) or T2* gradient echo (GRE) features of germinomas and non-germinomatous germ cell tumors (NGGCTs) in midline and off-midline locations.
We retrospectively evaluated all consecutive pediatric patients referred to our institution between 2005 and 2016, for newly diagnosed, treatment-naïve intracranial GCT, who underwent MRI, including T2*-based MR imaging (T2* GRE sequences or SWI). Standard pre- and post-contrast T1- and T2-weighted imaging characteristics along with T2*-based MR imaging features of all lesions were evaluated. Diagnosis was performed in accordance with the SIOP CNS GCT protocol criteria.
Twenty-four subjects met the inclusion criteria (17 males and 7 females). There were 17 patients with germinomas, including 5 basal ganglia primaries, and 7 patients with secreting NGGCT. All off-midline germinomas presented with SWI or GRE hypointensity; among midline GCT, all NGGCTs showed SWI or GRE hypointensity whereas all but one pure germinoma were isointense or hyperintense to normal parenchyma. A significant difference emerged on T2*-based MR imaging among midline germinomas, NGGCTs, and off-midline germinomas (p < 0.001).
Assessment of the SWI or GRE characteristics of intracranial GCT may potentially assist in differentiating pure germinomas from NGGCT and in the characterization of basal ganglia involvement. T2*-based MR imaging is recommended in case of suspected intracranial GCT.
基于T2的磁共振成像（MRI）在颅内生殖细胞肿瘤（GCT）中的作用尚未完全阐明。本研究的目的是评估生殖细胞瘤和非生殖细胞性生殖细胞肿瘤（NGGCT）在中线和中线旁部位的磁敏感加权成像（SWI）或T2梯度回波（GRE）特征。
我们回顾性评估了2005年至2016年间转诊至我院的所有连续儿科患者，这些患者为新诊断的、未经治疗的颅内GCT，均接受了MRI检查，包括基于T2的MRI（T2 GRE序列或SWI）。评估了所有病变的标准对比剂前后T1加权和T2加权成像特征以及基于T2*的MRI特征。诊断按照SIOP CNS GCT方案标准进行。
24名受试者符合纳入标准（17名男性和7名女性）。有17例生殖细胞瘤患者，包括5例基底节原发肿瘤，7例分泌性NGGCT患者。所有中线旁生殖细胞瘤均表现为SWI或GRE低信号；在中线GCT中，所有NGGCT均表现为SWI或GRE低信号，而除1例纯生殖细胞瘤外，其余均与正常实质等信号或高信号。中线生殖细胞瘤、NGGCT和中线旁生殖细胞瘤在基于T2*的MRI上存在显著差异（p < 0.001）。
评估颅内GCT的SWI或GRE特征可能有助于区分纯生殖细胞瘤和NGGCT，并有助于确定基底节受累情况。对于疑似颅内GCT的病例，建议进行基于T2*的MRI检查。
