起源于巨大先天性痣细胞痣的增生性结节1例及相关文献复习

Proliferative nodules arising from a giant congenital nevocytic nevus: a case report and review of the literatures

目的:探讨起源于巨大先天性痣细胞痣的增生性结节的组织病理特点及其与先天性痣细胞痣恶变的鉴别诊断。方法:对1例起源于婴儿巨大先天性痣细胞痣的增生性结节的临床表现、组织形态学、免疫组化及荧光原位杂交(FISH)特点进行分析并复习相关文献。结果:患儿男,4个月。自出生起全身多处皮肤可见大片黑斑;出生后3个月背部皮肤斑块上散在多个黑色疱状小结节,逐渐增大,个别结节出现破溃。皮损组织病理检查示皮内先天性痣细胞痣背景中可见形态较一致的尤因氏肉瘤细胞样细胞局灶结节状增生,核质比高,核分裂象2~4/mm^2,有坏死。免疫组化示结节状增生细胞D型细胞周期蛋白(cyclinD)1(50%+)、增殖核抗原(Ki-67)(5%~10%+)、HMB-45(灶状+)、melan-A(灶状+)及S-100蛋白(弥漫+)。FISH显示增生细胞具有分布于多条染色体的多个基因位点(包括6q23、6p25、6p11.1-q11.1、9p21、9q21、11q13、11p11.1-q11.1、17q12、17p11.1-q11.1)拷贝数增多。结论:起源于巨大先天性痣细胞痣的增生性结节常表现为细胞形态幼稚和增生活跃,Ki-67和FISH检测有助于其与痣恶变的鉴别。

Objective： To investigate the pathological features of proliferative nodules（PNs） arising from a giant congenital nevocytic nevus（GCNN） and its differential diagnosis with malignant nevus arising from benign congenital nevus. Methods： A case of PN originated from GCNN in an infant was analyzed in regards to the clinical manifestations, histology, immunohisto- chemistry and fluorescence in situ hybridization（FISH）. In addition, related literatures were reviewed. Results： A 4-month-old boy presented with multiple large black patches at birth. 3 months later nodules appeared on the patche of the back, and gradually increased in size. And ulceration occurred on nodules. Histopathological examination showed nodular proliferation of Ewing＇s sarcoma-like cells in GCNN-involved area of the skin. These proliferative cells had high nucleus/cytoplasm ratio, with mitotic figures of 2-4 per mm2. Necrosis and ulceration were evident. Immunohistochemistry showed that nodular proliferative cells were positive for CyclinDl（50%＋）, Ki-67（5%-10%＋）, HMB-45（focal＋）, melan-A（focal＋） and S-100 protein（diffuse＋）. FISH showed that the proliferative cells exhibited an increased copy number of multiple loci（6q23, 6p25, 6p11.1-q11.1, 9p21, 9q21, 11q13, 11p11.1-q11.1, 17q12 and 17p11.1-q11.1） in multiple chromosomes. Conclusions： PNs arising from a GCNN display immature proliferating cells and active proliferation. Ki-67 immnnostaining and FISH tests could be helpful for differential diagnosis of this disorder with others.