Yorita Kenji, Yonei Akihiro, Ayabe Takanori, Nakada Hiroshi, Nakashima Ken, Fukushima Tsuyoshi, Kataoka Hiroaki
Section of Oncopathology and Regenerative Biology, Department of Pathology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
J Med Case Rep. 2014 Oct 15;8:345. doi: 10.1186/1752-1947-8-345.
Ganglioneuroma is a rare tumor in the posterior mediastinum; fat-containing ganglioneuromas are rarely reported. The present case report documents a brown fat-containing, posterior mediastinal ganglioneuroma, which has not been reported previously. Radiological examination, in particular 18F-2-fluoro-2-deoxyglucose-positron emission tomography, suggested that the tumor had low-grade malignant potential. This led to uncertainty at preoperative diagnosis.
An asymptomatic 66-year-old Japanese woman with no significant past medical history was referred for the evaluation of a posterior mediastinal mass. Although its size had not changed in the past 5 years, a malignant lipomatous tumor could not be excluded due to the presence of intratumoral fat and increased 18F-2-fluoro-2-deoxyglucose uptake observed by positron emission tomography imaging. A computed tomography-guided core-needle biopsy revealed a mixture of mature adipocytes, spindle-shaped cells, and fibrotic stroma. Definite diagnosis was not possible, and surgical resection was performed. Three years after the surgery, she remains disease-free.
Histological diagnosis of the surgically resected mass confirmed ganglioneuroma with substantial amounts of white and brown adipose tissues in peripheral areas. The existence of both ganglion cells and brown fat tissue intensified the accumulation of 18F-2-fluoro-2-deoxyglucose, resulting in a false-positive result by positron emission tomography. Considering this, ganglioneuroma should not be excluded either clinically or pathologically in fat-containing, posterior mediastinal tumors.
神经节神经瘤是后纵隔的一种罕见肿瘤；含脂肪的神经节神经瘤鲜有报道。本病例报告记录了一例含棕色脂肪的后纵隔神经节神经瘤，此前未见报道。影像学检查，尤其是18F - 2 - 氟 - 2 - 脱氧葡萄糖正电子发射断层扫描，提示该肿瘤具有低度恶性潜能。这导致术前诊断存在不确定性。
一名66岁无症状日本女性，既往无重大病史，因后纵隔肿物前来评估。尽管肿物大小在过去5年未变，但由于肿瘤内存在脂肪且正电子发射断层扫描成像显示18F - 2 - 氟 - 2 - 脱氧葡萄糖摄取增加，不能排除恶性脂肪瘤性肿瘤。计算机断层扫描引导下的粗针活检显示为成熟脂肪细胞、梭形细胞和纤维性基质的混合物。无法明确诊断，遂行手术切除。术后三年，她仍无疾病复发。
手术切除肿物的组织学诊断证实为神经节神经瘤，外周区域有大量白色和棕色脂肪组织。神经节细胞和棕色脂肪组织的存在增强了18F - 2 - 氟 - 2 - 脱氧葡萄糖的积聚，导致正电子发射断层扫描出现假阳性结果。考虑到这一点，在含脂肪的后纵隔肿瘤的临床或病理诊断中不应排除神经节神经瘤。
