眼表鳞状上皮肿瘤的组织病理学与活体共聚焦显微镜影像学特征分析

摘要

目的 探讨眼表鳞状上皮肿瘤(OSSN)的组织病理学表现、活体共聚焦显微镜(IVCM)影像学特征及IVCM相关参数在OSSN诊断及鉴别诊断中的作用.方法 前瞻性研究.选取2015年9月至2017年11月在首都医科大学附属北京同仁医院北京同仁眼科中心初步诊断为角结膜肿瘤并拟行手术治疗的患者23例(23只眼).所有患者采集病史信息并按如下顺序进行检查:(1)视力检查;(2)眼表裂隙灯显微镜检查及外眼照相;(3)彩色眼底照相;(4)病灶区眼前节相干光层析成像术检查;(5)IVCM检查;(6)肿瘤切除后组织病理学检查.根据术后组织病理学诊断将患者分为两组:结膜上皮内瘤变(CIN)组和鳞状细胞癌(SCC)组.对比组织病理学检查结果 ,分析眼表肿瘤在IVCM中的表现特点(细胞形态、细胞质、细胞核等变化情况)及IVCM重要参数在CIN与SCC鉴别中的作用.两组患者临床症状、体征及IVCM重要参数的比较采用χ2检验或Fisher精确检验,IVCM参数诊断作用分析采用受试者工作特征曲线及计算曲线下面积完成.结果23例OSSN患者中男性12例,女性11例,年龄(62±15)岁.根据病理诊断结果,CIN组15例(15只眼),SCC组8例(8只眼).CIN组和SCC组患者眼红、眼痛、异物感及流泪症状比例差异无统计学意义(均P>0.05);体征方面,SCC组肿物基底部最大直径[8.5(6.5～15.5)mm]和病灶区滋养血管增生出现比例(7/8)均大于CIN组[5.8(4.0～8.5)mm;5/15],差异有统计学意义(Z=4.702,P=0.029;χ2=6.135,P=0.013).组织病理学可见CIN患者角结膜上皮细胞层数增加,细胞呈多形性,胞质染色浓淡不一及少许浓染增大的细胞核;SCC患者角膜上皮细胞异型性明显,表现为核丝分裂象、细胞间桥及梭形细胞的出现.IVCM检查结果显示,CIN组与SCC组肿瘤上皮细胞大小不一、细胞质高反光以及核质比增高出现的比例差异无统计学意义(P=0.053、0.108、0.067);有丝分裂象、梭形细胞、漩涡状细胞巢结构以及浅基质层异常细胞在SCC组出现的比例(8/8、8/8、8/8、8/8)高于CIN组(2/15、1/15、4/15、0/15),差异均有统计学意义(P=0.001、0.001、0.003,P<0.001).IVCM诊断参数中,浅基质层出现异常细胞对SCC具有最高诊断价值,曲线下面积为1.000;另外,胞核有丝分裂象、梭形细胞以及漩涡状细胞巢结构3个IVCM评估参数的曲线下面积分别为0.933、0.901和0.867,对SCC诊断具有良好预测性.结论 角膜上皮细胞异型性、胞质高反光、核质比增高是OSSN在IVCM下的三大特征,而浅基质层异常细胞、核有丝分裂象及漩涡状细胞巢状结构的出现是鉴别CIN与SCC的主要IVCM参数.%Objective To study the histopathology manifestation and imaging characteristics of in vivo confocal microscopy (IVCM) for diagnosis of ocular surface squamous neoplasia (OSSN) and analyze the reliability of IVCM in differential diagnosis from OSSN cases. Methods A prospective study. Twenty-three patients (23 eyes) with OSSN were collected from September 2015 to November 2017 in Beijing Tongren Eye center. They were underwent the examinations sequentially as follows: visual examination; slit-lamp microscope examination and ocular surface photography; color fundus image; anterior segment optical coherence tomography examination; IVCM examination and histopathology examination after surgery. With histopathology diagnosis, all subjects were divided into two groups: conjunctival intraepithelial neoplasm (CIN) and squamous cell carcinoma (SCC). Compared with histopathological findings, the IVCM results (cell morphology, cytoplasm and nucleus) of OSSN were analyzed. The difference analysis between the count data of two groups was carried out by the chi square test or Fisher's exact test. Receiver operating characteristic curve and area under the curve (AUC) were used to describe the accuracy of each parameter to differentiate SCC from OSSN. Results There were 12 males and 11 females among the 23 patients aged (62±15) years. With the histopathological diagnosis, there were 15 cases (15 eyes) in the CIN group and 8 cases (8 eyes) in the SCC group. Eye redness, pain, foreign body sensation and tears were the symptoms of OSSN. There was no significant difference in clinical symptoms between the CIN and SCC groups. The size of tumors and the incidence of trophoblastic vessels in the SCC group were greater than those in the CIN group [8.5(6.5-15.5) mm vs. 5.8(4.0-8.5)mm, Z=4.702,P=0.029;7/8 vs. 5/15,χ2=6.135, P=0.013). In histopathology, multilayered epithelia with cellular polymorphism, varied cytoplasm staining, and slightly thicker nuclei were observed in the CIN group. The corneal epithelial cells of SCC patients were markedly heterogeneous, and the intercellular bridge structure can be detected. Proliferative cells appeared with spindle shaped cells, nuclear mitotic figures and syncytial cells in the SCC group. The IVCM examination in the CIN group and SCC group showed that the cytoplasm was high and the ratio of nuclear plasma increased. There was no significant difference between the two groups in the size of epithelial cells, cytoplasm reflectivity, and nuclear cytoplasm ratio (P=0.053,0.108,0.067). The proportions of nuclear mitotic figures, spindle or chimeric cells, nests of whirlpool cells and the abnormal cells of the superficial stroma layer(8/8, 8/8, 8/8 and 8/8)in the SCC group was higher than those(2/15, 1/15, 4/15 and 0/15) in the CIN group,and the difference was statistically significant (P=0.001, 0.001, 0.003; P<0.001). Among these IVCM parameters, the abnormal cells of the superficial stroma layer had the highest diagnostic ability with the AUC value of 1.000, and the following AUC values were 0.933 for mitotic or double nuclei, 0.901 for spindle or chimeric cells, and 0.867 for the nests of whirlpool cells. Conclusions The IVCM characteristics of OSSN are the dysplastic cells, hyper-reflective cytoplasm and increased nuclear plasma ratio in the corneal epithelium. Dysplastic cells appearing in the superficial stroma layer, nuclear mitotic figures and nests of vortex cells are the main IVCM parameters to support the malignant change of OSSN lesions.