恶性蝾螈瘤的CT诊断价值

CT diagnostic values of malignant triton tumor

目的探讨恶性蝾螈瘤的临床、病理及CT表现,提高对该病的认识。方法收集经手术病理确诊的3例恶性蝾螈瘤患者的临床、病理及CT扫描资料。男1例,女2例,其中2例行腹部CT平扫加双期增强扫描,1例行颈部CT平扫加增强扫描。结合文献复习,对照3例恶性蝾螈瘤的CT表现与病理结果,分析其CT表现的病理基础。结果3例病理镜下为恶性周围神经鞘瘤中,出现散在横纹肌母细胞成分,免疫组化提示存在神经细胞成分:WT1、S-100、NF均阳性;肌性成分:HHF-35(+),Vimentin(+),Myogenin(+),2例desmin(+)和myoglobin(+),提示有横纹肌肉瘤成分。3例实验室检查中2例乳酸脱氢酶升高,1例神经元特异性烯醇化酶(NSE)明显升高。CT表现为囊实性或实性肿块,瘤体内可有囊变或坏死,增强后强化不均匀,常伴有周围软组织浸润及骨质破坏,短期内复查可迅速增大。结论恶性蝾螈瘤是含有横纹肌肉瘤成分的恶性神经鞘瘤,临床、实验室及CT检查难以确诊,需借助病理及免疫组织化学才能确诊,而CT检查价值在于对病变的定位、了解周围结构及有无复发、转移。

Objective To discuss clinical, pathology and CT manifestation of Malignant Triton Tumor （MTT）. Methods CT findings of three cases of Triton Tumor were investigated by using abdominal pre-contrast and dual-phase enhancement scanning in two cases, another case underwent cervical pre-contrast and enhancement scanning, CT appearances were analyzed and contrasted with pathology. Literature was also reviewed. Results The appearance of microscope is malignant peripheral nerve sheath tumor accompanied with striated muscle cell. Immunity histochemistry showed positive WT1, S-100, NF and positive HHF-35, Vimentin, Myogenin in all three cases, while desmin and myoglobin were positive in two cases. Lactic acid dehydrogenase （LDH） elevated in 2 cases and neuron specific enolase （NSE） elevated markedly in 1 case .CT presents as a soft tissue mass with necrosis or cystis degeneration. The mass was enhanced irregularly, and the solid component was well enhanced. Conclusion Malignant triton tumor is the malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation, while both clinical laboratory and CT are difficult to diagnosis and the diagnosis depends on pathology and histochemistry. The value of CT is to clarity the location, its encroachment and metastasis.