Sun Xue, Zhao Li
VIP Department and General Medicine Department, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, China 100730.
Department of Gastroenterology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, China 100730.
Gastroenterol Res Pract. 2020 Mar 31;2020:2105874. doi: 10.1155/2020/2105874. eCollection 2020.
Linked color imaging (LCI) helps screen and diagnose for early gastric cancer by color contrast in different mucosa. RGB (red, green, and blue) pixel brightness quantifies colors, which is relatively objective. Limited studies have combined LCI images with RGB to help screen for early gastric cancer (EGC). We aimed to evaluate the RGB pixel brightness characteristics of EGC and noncancer areas in LCI images.
We retrospectively reviewed early gastric cancer (EGC) patients and LCI images. All pictures were evaluated by at least two endoscopic physicians. RGB pixel brightness analysis of LCI images was performed in MATLAB software to compare the cancer with noncancer areas. Receiver operating characteristic (ROC) curve was analyzed for sensitivity, specificity, cut-off, and area under the curve (AUC).
Overall, 38 early gastric cancer patients were enrolled with 38 LCI images. Pixel brightness of red, green, and blue in cancer was remarkably higher than those in noncancer areas (190.24 ± 37.10 vs. 160.00 ± 40.35, < 0.001; 117.96 ± 33.91 vs. 105.33 ± 30.01, = 0.039; 114.36 ± 34.88 vs. 90.93 ± 30.14, < 0.001, respectively). (Hp) infection was not relevant to RGB distribution of EGC. Whether the score of Kyoto Classification of Gastritis (KCG) is ≥4 or <4, the pixel brightness of red, green, and blue was not disturbed in both cancer and noncancer ( > 0.05). Receiver operating characteristic (ROC) curve for differentiating cancer from noncancer was calculated. The maximum area under the curve (AUC) was 0.767 in B/G, with a sensitivity of 0.605, a specificity of 0.921, and a cut-off of 0.97.
RGB pixel brightness was useful and more objective in distinguishing early gastric cancer for LCI images.
联动成像（LCI）通过不同黏膜的颜色对比有助于早期胃癌的筛查与诊断。RGB（红、绿、蓝）像素亮度可对颜色进行量化，相对较为客观。将LCI图像与RGB相结合以辅助早期胃癌（EGC）筛查的研究较少。我们旨在评估LCI图像中EGC及非癌区域的RGB像素亮度特征。
我们回顾性分析了早期胃癌患者及LCI图像。所有图片均由至少两名内镜医师进行评估。在MATLAB软件中对LCI图像进行RGB像素亮度分析，以比较癌灶与非癌区域。分析受试者工作特征（ROC）曲线的敏感性、特异性、截断值及曲线下面积（AUC）。
总体而言，纳入了38例早期胃癌患者及38幅LCI图像。癌灶中红色、绿色和蓝色的像素亮度显著高于非癌区域（分别为190.24±37.10对160.00±40.35，<0.001；117.96±33.91对105.33±30.01，=0.039；114.36±34.88对90.93±30.14，<0.001）。幽门螺杆菌（Hp）感染与EGC的RGB分布无关。无论胃炎京都分类（KCG）评分≥4或<4，癌灶和非癌区域中红色、绿色和蓝色的像素亮度均无明显差异（>0.05）。计算区分癌灶与非癌区域的受试者工作特征（ROC）曲线。B/G的最大曲线下面积（AUC）为0.767，敏感性为0.605，特异性为0.921，截断值为0.97。
RGB像素亮度在区分LCI图像中的早期胃癌方面有用且更客观。
