检测COL1A1-PDGFB融合基因协助诊断萎缩型隆突性皮肤纤维肉瘤

Auxiliary diagnosis of atrophic dermatofibrosarcoma protuberans by detecting COL1A1-PDGFB gene fusion

报告1例萎缩型隆突性皮肤纤维肉瘤。患者女,24岁。患者2年前无明显诱因胸部皮肤出现红斑,逐渐变大,中央萎缩。皮肤科检查:胸部一3 cm×4 cm暗紫红色近圆形斑块,表面光滑,中央萎缩,触之质地韧,无凸起包块,无触痛。皮损组织病理检查:表皮轻度乳头瘤样增生,真皮萎缩变薄,真皮及皮下脂肪可见短梭形细胞增生,增生细胞和表皮之间可见肿瘤细胞无浸润带;真皮浅、中层区域肿瘤细胞数目较少,排列稍稀疏,细胞呈波浪状排列,平行于表皮;真皮深部和皮下脂肪层可见密集排列的梭形细胞增生,梭形细胞密集排列呈车幅状、席纹状或束状。免疫组化示肿瘤细胞强阳性表达CD34。采用反转录-聚合酶链式反应(RT-PCR)检测COL1A1-PDGFB融合基因阳性。诊断:萎缩型隆突性皮肤纤维肉瘤。

A case of atrophic dermatofibrosarcoma protuberans(DFSPs) is reported. A 24-year-old woman presented with a 2-year history of an asymptomatic, slowly enlarging erythema on the chest. Physical examination showed a dark-purple, smooth,round plaque sized 3 cm×4 cm, with central atrophy, on the chest. On palpation the lesion was solid with no tenderness. Histopathologi cal examination revealed mild papillomatous hyperplasia in the epidermis and dermal atrophy. Hyperplasia of short spindle cells were ob served in the dermis and subcutaneous fat tissue. Infiltrate-free zone was also seen between proliferating cells and the epidermis. In the upper and middle dermis, few proliferating cells were loosely arranged in wave pattern in parallel with the epidermis. In the low er dermis and subcutaneous tissue, spindle cells were arranged in storiform or sarciniform patterns. Immunohistochemistry showed the tumor cells were positive for CD34. COL1 A1-PDGFB gene fusion was detected by RT-PCR. The diagnosis of atrophic DFSPs was made.