Bentley R Timothy, Yanke Amy B, Miller Margaret A, Heng Hock Gan, Cohen-Gadol Aaron, Rossmeisl John H
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN, United States.
Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.
Front Vet Sci. 2021 May 3;8:650320. doi: 10.3389/fvets.2021.650320. eCollection 2021.
Dissemination of glioma in humans can occur as leptomeningeal nodules, diffuse leptomeningeal lesions, or ependymal lesions. Cerebrospinal fluid (CSF) drop metastasis of glioma is not well-recognized in dogs. Ten dogs with at least two anatomically distinct and histologically confirmed foci of glioma were included in this study. The 10 dogs underwent 28 magnetic resonance imaging (MRI) examinations, with distant CSF drop metastasis revealed in 13 MRIs. The CSF drop metastases appeared as leptomeningeal nodules in four dogs, diffuse leptomeningeal lesions in six dogs, and ependymal lesions in seven dogs; six dogs had a combination of lesion types. Primary tumors were generally T2-heterogeneous and contrast-enhancing. Many metastases were T2-homogeneous and non-enhancing. Diffuse leptomeningeal lesions were seen as widespread extra-axial contrast-enhancement, again very dissimilar to the intra-axial primary mass. Primary masses were rostrotentorial, whereas metastases generally occurred in the direction of CSF flow, in ventricles, CSF cisterns, and the central canal or leptomeninges of the cervical or thoracolumbar spinal cord. Seven of the dogs had received therapy limited to the primary mass, such as surgery or stereotactic radiation, then developed metastasis in the following months. CSF drop metastasis of glioma may take a very different appearance on MRI to the primary mass, including periventricular lesions that are more homogeneous and less contrast-enhancing, rostral horn signal changes, or leptomeningeal enhancement ventral to the brainstem or encircling the spinal cord.
胶质瘤在人类中的播散可表现为软脑膜结节、弥漫性软脑膜病变或室管膜病变。胶质瘤的脑脊液播散转移在犬类中尚未得到充分认识。本研究纳入了10只患有至少两个解剖学上不同且经组织学证实的胶质瘤病灶的犬。这10只犬接受了28次磁共振成像（MRI）检查，其中13次MRI显示有远处脑脊液播散转移。脑脊液播散转移在4只犬中表现为软脑膜结节，6只犬中表现为弥漫性软脑膜病变，7只犬中表现为室管膜病变；6只犬有多种病变类型组合。原发性肿瘤通常在T2加权像上呈不均匀信号且有强化。许多转移灶在T2加权像上呈均匀信号且无强化。弥漫性软脑膜病变表现为广泛的脑外强化，与脑内原发性肿块截然不同。原发性肿块位于前脑幕区，而转移灶通常沿脑脊液流动方向发生，见于脑室、脑池、中央管或颈段或胸腰段脊髓的软脑膜。7只犬接受了局限于原发性肿块的治疗，如手术或立体定向放疗，随后在接下来的几个月内出现了转移。胶质瘤的脑脊液播散转移在MRI上的表现可能与原发性肿块非常不同，包括更均匀且强化较少的脑室周围病变、脑室前角信号改变，或脑干腹侧或脊髓周围的软脑膜强化。
