Mehrotra Sanjana, Pan Zenggang
Department of Pathology, University of Colorado School of Medicine, Aurora, Colorado.
Diagn Cytopathol. 2015 Aug;43(8):659-63. doi: 10.1002/dc.23285. Epub 2015 May 21.
Histiocytic sarcoma (HS) is a rare malignant tumor, and in extraordinary circumstances it can be transdifferentiated from a low-grade B-cell lymphoma. In our report, a 62-year-old female was initially diagnosed with a low-grade follicular lymphoma, and 2 years later she presented with bilateral lung masses and lymphadenopathy. Fine needle aspiration (FNA) of the lung masses revealed solid nests of large pleomorphic epithelioid cells. By immunohistochemical studies, the tumor cells were positive for histiocytic markers (CD68 and CD163) and S100, supporting a diagnosis of HS with dendritic cell differentiation. Further fluorescence in situ hybridization (FISH) analyses detected IGH@/BCL2 rearrangement in both the previous follicular lymphoma and the current HS, which was highly suggestive of the clonal relationship between these two tumors. To the best of our knowledge, this is the first case of transformation of follicular lymphoma into HS diagnosed by FNA of lung masses.
组织细胞肉瘤（HS）是一种罕见的恶性肿瘤，在特殊情况下，它可由低级别B细胞淋巴瘤转分化而来。在我们的报告中，一名62岁女性最初被诊断为低级别滤泡性淋巴瘤，2年后她出现双侧肺肿块和淋巴结病。肺肿块的细针穿刺活检（FNA）显示为实性巢状的大的多形性上皮样细胞。通过免疫组化研究，肿瘤细胞的组织细胞标志物（CD68和CD163）及S100呈阳性，支持诊断为具有树突状细胞分化的HS。进一步的荧光原位杂交（FISH）分析在先前的滤泡性淋巴瘤和当前的HS中均检测到IGH@/BCL2重排，这强烈提示这两种肿瘤之间的克隆关系。据我们所知，这是首例通过肺肿块FNA诊断滤泡性淋巴瘤转化为HS的病例。
