Mazur Marcus D, Nguyen Vinh, Fults Daniel W
Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT 84132, USA.
Case Rep Neurol Med. 2012;2012:816873. doi: 10.1155/2012/816873. Epub 2012 Jul 11.
Corticosteroid-induced reduction in contrast enhancement on radiographic imaging is most commonly associated with lymphoma but has been reported in other entities, including glioma. This finding may represent a diagnostic dilemma. Concern that steroid-induced cytotoxicity obscures histological diagnosis of suspected lymphoma may lead to postponement of a biopsy. If glioma is not considered in the differential diagnosis, reduction in tumor contrast enhancement may be misinterpreted as disease regression rather than a transient radiographic change. We report a case of a patient with an enhancing right temporoparietal mass adjacent to the atrium of the lateral ventricle. After treatment with dexamethasone was started, the mass exhibited marked reduction in contrast enhancement, with symptom improvement. The clinical course suggested lymphoma, and surgery was not performed. Subsequent screening for extra-axial lymphoma was negative. Two weeks later, the patient developed worsening symptoms, and repeat T1-weighted imaging showed interval increase in size and enhancement. The findings suggested a possible diagnosis of malignant glioma. The patient underwent a stereotactic-guided craniotomy for excision of the right temporoparietal mass lesion. Final histological diagnosis was glioblastoma multiforme, World Health Organization grade IV.
皮质类固醇导致的影像学上对比增强的降低最常与淋巴瘤相关，但在包括胶质瘤在内的其他实体中也有报道。这一发现可能代表一种诊断困境。担心类固醇诱导的细胞毒性会掩盖疑似淋巴瘤的组织学诊断可能导致活检推迟。如果在鉴别诊断中未考虑胶质瘤，肿瘤对比增强的降低可能会被误解为疾病消退而非一过性影像学改变。我们报告一例患者，其右侧颞顶叶有一增强肿块，毗邻侧脑室心房。开始用地塞米松治疗后，肿块的对比增强显著降低，症状改善。临床病程提示为淋巴瘤，未进行手术。随后的轴外淋巴瘤筛查为阴性。两周后，患者症状加重，复查T1加权成像显示肿块大小和强化有间隔性增加。这些发现提示可能诊断为恶性胶质瘤。患者接受了立体定向引导下的开颅手术，以切除右侧颞顶叶肿块病变。最终组织学诊断为多形性胶质母细胞瘤，世界卫生组织IV级。
