Zhan He-Qin, Chen Hong, Wang Chao-Fu, Zhu Xiong-Zeng
Department of Pathology, Anhui Medical University, Hefei 230032, China.
Department of Pathology, The First Hospital Fujian Medical University, Fuzhou 350005, China.
Hum Pathol. 2015 Mar;46(3):476-81. doi: 10.1016/j.humpath.2014.11.013. Epub 2014 Dec 9.
Xp11.2 translocation renal cell carcinoma (Xp11.2 RCC) with PSF-TFE3 gene fusion is a rare neoplasm. Only 22 cases of Xp11.2 RCCs with PSF-TFE3 have been reported to date. We describe an additional case of Xp11.2 RCC with PSF-TFE3 showing melanotic features. Microscopically, the histologic features mimic clear cell renal cell carcinoma. However, the dark-brown pigments were identified and could be demonstrated as melanins. Immunohistochemically, the tumor cells were widely positive for CD10, human melanoma black 45, and TFE3 but negative for cytokeratins, vimentin, Melan-A, microphthalmia-associated transcription factor, smooth muscle actin, and S-100 protein. Genetically, we demonstrated PSF-TFE3 fusion between exon 9 of PSF and exon 5 of TFE3. The patient was free of disease with 50 months of follow-up. The prognosis of this type of tumor requires more cases because of limited number of cases and follow-up period. Xp11.2 RCC with PSF-TFE3 inevitably requires differentiation from other kidney neoplasms. Immunohistochemical and molecular genetic analyses are essential for accurate diagnosis.
伴有PSF-TFE3基因融合的Xp11.2易位性肾细胞癌（Xp11.2 RCC）是一种罕见肿瘤。迄今为止，仅有22例伴有PSF-TFE3的Xp11.2 RCC病例被报道。我们描述了1例伴有PSF-TFE3且具有黑素沉着特征的Xp11.2 RCC的额外病例。显微镜下，组织学特征类似透明细胞肾细胞癌。然而，发现了深棕色色素，且可证实为黑色素。免疫组化方面，肿瘤细胞CD10、人黑色素瘤黑色45和TFE3广泛阳性，但细胞角蛋白、波形蛋白、Melan-A、小眼相关转录因子、平滑肌肌动蛋白和S-100蛋白阴性。遗传学上，我们证实了PSF第9外显子与TFE3第5外显子之间存在PSF-TFE3融合。该患者随访50个月无疾病复发。由于病例数量和随访时间有限，这类肿瘤的预后情况需要更多病例来明确。伴有PSF-TFE3的Xp11.2 RCC不可避免地需要与其他肾肿瘤相鉴别。免疫组化和分子遗传学分析对于准确诊断至关重要。
