左腋下放疗后隆突性皮肤纤维肉瘤妊娠期迅速增大一例

Accelerated growth of postradiation dermatofibrosarcoma protuberans in left subaxillary region during pregnancy： a case report

患者女，30岁。5年前因左乳腺癌行保乳手术并接受放射治疗，在左腋下出现放射性皮炎。2年后，在放射性皮炎部位出现3个黄豆大小的鲜红色结节，逐渐增大，行手术切除3周后复发。妊娠后肿块迅速增大、隆起，终止妊娠后，肿块增大趋势得到明显遏制。皮肤科检查：左腋下方见18cm×14cm类似椭圆形暗红色或鲜红色斑块，斑块表面光滑，中央为10cm×9cm×5cm大的鲜红色半球形实质性隆起，表面糜烂，结痂。组织病理：真皮中下层致密、单一的梭形细胞排列成漩涡状、席纹状。部分细胞核有异形性，少见核分裂象。少数区域瘤细胞排列成“青鱼骨”状。免疫组化染色：波形蛋白（＋＋＋），肌动蛋白（＋），CD34阴性。诊断：放疗后隆突性皮肤纤维肉瘤（纤维肉瘤型）。

A 30-year-old woman presented with a 5-year history of recurrent nodular lesions in the left subaxillary region, which had rapidly grown for 7 weeks. Five years prior to the presentation, she received breast conservation surgery and radiotherapy for left breast cancer, thereafter, chronic radiation dermatitis developed in the left subaxillary region. Two years after the operation, three soybean-sized bright red nodules appeared in the lesions of radiation dermatitis, and slowly enlarged. Subsequently, the nodules were resected, but a local recurrence was observed 3 weeks after the resection. The recurrent masses underwent accelerated growth during her pregnancy, and the growth was obviously inhibited after the termination of pregnancy. Physical examination revealed a quasi-elliptic, dark or bright red plaque measuring about 18 cm× 14 cm with a smooth surface in left subaxillary region, and in the center of the plaque was a bright red, hemispheric, elevated lesion measuring 10 cm × 9 cm × 5 cm with erosions or pitchy crusts on the surface. Histopathology of the lesions showed that the tumor was located in the dermis and consisted of densely packed uniform spindle-shaped cells arranged in a characteristic storiform or whirlpool pattern. Some cell nuclei showed atypia, and few mitoses were observed. In some parts of the lesion, tumor cells were arranged in a herringbone pattern. Immunohistochemistry revealed that the tumor cells stained positive for vimentin （strongly） and actin （weakly）, but negative for CD34. Based on these findings, a diagnosis of postradiation dermatofibrosarcoma protuberans （fibrosarcoma type） was made.