滤泡树突细胞肉瘤英文
Korean J Radiol. 2011 Jan-Feb; 12(1): 122–128.
Published online 2011 January 3. doi:
? 2011 The Korean Society of Radiology PMCID: PMC3017876 Imaging Findings of Follicular Dendritic Cell Sarcoma: Report of Four Cases
Qiu Long-Hua, MD,1 Xiao Qin, MD,2 Gu Ya-Jia, MD,2 Wang Jian, MD,3 and Feng Xiao-Yuan, MD1
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o Other Sections? AbstractINTRODUCTIONCASE
REPORTSDISCUSSIONSummaryReferencesDISCUSSION
Imaging Features and Differential Diagnosis
In the current study, the sizes of the follicular dendritic cell sarcomas of the four patients ranged from 1.5 to 15 cm. The mediastinal (7.5 cm) and intraabdominal lesions (15 cm) were much larger than the lesions located in the neck (4.5 cm and 1.5 cm). Consistent with our results, some previous studies (5-7) have also suggested that the intraabdominal tumors were bigger than those that occurred outside the abdominal cavity.
According to the cases of follicular dendritic cell sarcoma reported in the literature (3-11), the average sizes of the 38 reported abdominal lesions and the 11 mediastinal lesions were 10.7 cm (range: 3.5 to 22 cm) and 6.7 cm (range: 3 to 10 cm), respectively, whereas 18 of the 19 lesions in the neck (and
that originated from the cervical lymph nodes) were smaller than 6 cm. The tumor margins of our cases were generally well defined. Their CT attenuation was variable, and the tumors demonstrated relatively homogeneous attenuation in the lesions of the cervical lymph nodes, but they showed heterogeneous attenuation in the large abdominal lesion. Similar to our case of abdominal follicular dendritic sarcoma, areas of gross intratumoral necrosis or hemorrhage were noted in 32 of the 38 (84%) intraabdominal cases reported in the literature and Kang et al. (4) suggested a well-defined mass with internal necrosis was the CT findings of a follicular dendritic cell sarcoma of the abdomen. The
presence of gross necrosis in the abdominal lesions may be related to the tumor size, as a large tumor is prone to cystic degeneration or necrosis. Few studies have evaluated the vascularity of follicular dendritic cell sarcomas. Leipsic et al. (3) suggested indistinctly that a follicular dendritic cell sarcoma might be a relatively hypovascular lesion
according to their surgery report, but this was not consistent with our findings. In our study, the first case in the mediastinum showed marked enhancement after the administration of intravascular contrast media and the tumor was shown to be hypervascular at surgery. Also, in the second case in the abdomen, prominent feeding vessels were noted in the lesion's periphery, although the degree of tumor enhancement after contrast administration was lower than that of the liver. These results may suggest that
at least some follicular dendritic cell sarcomas are not hypovascular as was reported previously (3). More cases are necessary to clarify the vascularity of follicular dendritic cell sarcomas.
In our study, the CT findings of the first case that occurred in the mediastinum, including a round homogeneous mass, intense enhancement and arborizing calcifications, were quite similar to those of Castleman disease (12). "Castleman disease-like" intratumoral calcification was also noted in another previously reported mediastinal lesion (3).
Moreover, a subset of follicular dendritic cell sarcomas has been reported to arise in or concomitantly with foci of Castleman disease (3). Therefore, the radiological distinction between follicular dendritic cell sarcoma and Castleman disease in the mediastinum could be quite difficult and this needs more accumulated cases and further investigation.
Some of the cases of follicular dendritic cell sarcomas reported in the literature and that involved the gastrointestinal tract were initially misdiagnosed as gastrointestinal stromal tumors (13, 14). Similarly, our second case was initially misdiagnosed as a gastrointestinal stromal
tumor. Even if a follicular dendritic cell sarcoma is included in the differential list for a large stromal tumor-like abdominal mass seen on imaging, making a further specific diagnosis is not possible due to the generally nonspecific nature of the imaging findings.
The two cases of follicular dendritic cell sarcomas that involved the
cervical lymph nodes in our series presented as well-delineated
homogeneous masses. These features may help distinguishing follicular dendritic cell sarcomas from cervical metastatic carcinoma or schwannoma, as the latter tumors often show heterogeneous lesion attenuation due to central necrosis and infiltrating borders.