Validation of a classification and scoring system for the diagnosis of laryngeal and pharyngeal squamous cell carcinomas by confocal laser endomicroscopy

Abstract Introduction: Confocal laser endomicroscopy is an optical imaging technique that allows in vivo, real-time, microscope-like images of the upper aerodigestive tract’s mucosa. The assessment of morphological tissue characteristics for the correct differentiation between healthy and malignant suspected mucosa requires strict evaluation criteria. Objective: This study aims to validate an eight-point score for the correct assessment of malignancy. Methods: We performed confocal laser endomicroscopy between March and October 2020 in 13 patients. 197 sequences (11.820 images) originated from the marginal area of pharyngeal and laryngeal carcinomas. Specimens were taken at corresponding locations and analyzed in H&E staining as a standard of reference. A total of six examiners evaluated the sequences based on a scoring system; they were blinded to the histopathological examination. The primary endpoints are sensitivity, specificity, and accuracy. Secondary endpoints are interrater reliability and receiver operator characteristics. Results: Healthy mucosa showed epithelium with uniform size and shape with distinct cytoplasmic membranes and regular vessel architecture. Confocal laser endomicroscopy of malignant cells demonstrated a disorganized arrangement of variable cellular morphology. We calculated an accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 83.2%, 81.3%, 85.5%, 86.7%, and 79.7%, respectively, with a κ-value of 0.64, and an area under the curve of 0.86. Conclusion: The results confirm that this scoring system is applicable in the laryngeal and pharyngeal mucosa to classify benign and malignant tissue. A scoring system based on defined and reproducible characteristics can help translate this experimental method to broad clinical practice in head and neck diagnosis.

摘要 引言：共聚焦激光内镜显微镜（Confocal laser endomicroscopy）是一种光学成像技术，可获取上呼吸消化道黏膜的活体、实时类显微镜图像。对组织形态特征进行评估以准确区分健康黏膜与疑似恶性黏膜，需遵循严格的评价标准。
研究目的：本研究旨在验证一款8分评分系统，用于恶性病变的准确评估。
研究方法：本研究于2020年3月至10月期间纳入13例患者开展共聚焦激光内镜显微镜检查，共获取197条序列（合计11820幅图像），均来源于咽喉部癌肿的边缘区域。在对应位置采集组织标本，以苏木精-伊红（H&E）染色作为参考金标准进行分析。共计6名评估者基于该评分系统对上述序列进行评估，且所有评估者均对组织病理学检查结果设盲。本研究的主要终点为灵敏度、特异度及准确度；次要终点为评定者间信度与受试者工作特征曲线。
研究结果：健康黏膜的上皮细胞大小与形态均一，胞膜清晰，血管结构规则；恶性病变的共聚焦激光内镜显微镜成像则可见细胞形态各异且排列紊乱。本研究计算得出的准确度、灵敏度、特异度、阳性预测值及阴性预测值分别为83.2%、81.3%、85.5%、86.7%及79.7%，Kappa值为0.64，曲线下面积为0.86。
研究结论：本研究结果证实，该评分系统可应用于咽喉部黏膜良恶性组织的分类。基于明确且可重复的特征构建的评分系统，有助于将这一实验性技术推广至头颈部诊断的广泛临床实践中。