| Background and Purpose:The incidence and mortality of malignant tumors in the world today are high,which is a major threat to human health.Compared with advanced cancers,the prognosis of early digestive cancers are much better.Therefore the diagnosis of early digestive cancer is very important.At present,the common approach to diagnose early gastrointestinal cancer is endoscopic techniques,supplemented by serological test,imaging test and pathological test.Raman spectroscopy,which has the advantages of non-invasive,objective,fast and high accuracy,is a new method to diagnose cancers.In this study,Raman spectral data were obtained by the fiber Raman system from endoscopic submucosal dssection(ESD)tissues in vitro of early esophageal cancer,early gastric cancer and non-lesion and tissues in vivo of early gastric cancer and non-lesion.These data is analyzed to diagnose early esophageal and gastric cancers and to explore the application of fiber Raman system in the diagnosis of early esophageal cancer,gastric cancer and precancerous lesions.Approach:ESD specimens were collected from 16 patients with early esophageal cancer,11 patients with low-grade intraepithelial neoplasia(LGIN)of the stomach,10 patients with high-grade intraepithelial neoplasia(HGIN)of the stomach and 11 patients with early gastric cancer,and standard Raman spectral data of diseased tissues in vitro were obtained by the fiber Raman system.Raman spectral data in vivo from 14 patients of gastric cancer and nonlesion were also obstained.After preprocessing steps,the average Raman spectrum was obtained.Then material assignments of Raman peaks were analyzed and statistical methods were used to analyze the integrated energy ratio and peak intensity ratio between diseased tissues and nonlesional tissues.Results:1.The average in vitro Raman spectrum of nonlesional tissues,LGIN tissues and HGIN tissues from ESD specimens of stomach: There are differences among the shape of the average Raman spectrum and some material assignments of Raman peaks of the three groups: 1)Significant Raman peaks corresponding to the nonlesional tissues appear at 852 cm-1?891 cm-1?992 cm-1?1103 cm-1?1171 cm-1?1234 cm-1?1417 cm-1?1560 cm-1?1586 cm-1.By contrast,corresponding Raman peaks of LGIN tissues and HGIN tissues shifts to some extent.2)Characteristic peaks appeare at 1479 cm-1 in the average Raman spectrum of the nonlesional tissues,at 805 cm-1?819 cm-1?1306 cm-1?1327 cm-1 in the average Raman spectrum of the LGIN tissues and at 875 cm-1?1304 cm-1?1324 cm-1 in the average Raman spectrum of the HGIN tissues.2.The average in vitro Raman spectrum of nonlesional tissues and diseased tissues,including HGIN and early adenocarcinoma,from ESD specimens of stomach: 1)There are differences between the shape of the average Raman spectrum and some material assignments of Raman peaks of the two groups: some Raman peaks observed in nonlesional tissues were not observed in the diseased tissues;Significant Raman peaks corresponding to the nonlesional tissues appear at 891 cm-1?992 cm-1?1103 cm-1?1206 cm-1?1234 cm-1?1292 cm-1 ? 1417 cm-1 ? 1560 cm-1 ? 1678 cm-1.By contrast,significant Raman peaks corresponding to the diseased tissues,including high-grade intraepithelial neoplasia and adenocarcinoma,were observed in the Raman spectra at 888 cm-1?987 cm-1?1101 cm-1?1209 cm-1?1236 cm-1?1294 cm-1?1413 cm-1?1562 cm-1?1682 cm-1;A characteristic peak appeares at 1479 cm-1 in the average Raman spectrum of the diseased tissues.2)There are statistical differences between the the integral energy ratio and the traditional peak intensity ratio of the two groups.The area under curve(AUC)of the integral energy ratio in the non-continuous frequency band(E1500—1600 cm-1/E1050—1150 cm-1)is 0.992,which means that with this non-continuous frequency band,the accuracy rate of identifying EGC is 99.2%,and the corresponding sensitivity and specificity are 93.9% and 95.5%,respectively;The AUC of the integral energy ratio in the continuous frequency band(E1350—1500 cm-1/E1200—1350 cm-1)is 0.996,which means that with this continuous frequency band,the accuracy rate of identifying EGC is 99.6%,and the corresponding sensitivity and specificity are 97.0% and 95.5%,respectively;The AUC of the peak intensity ratio of I1560 cm-1/I1103 cm-1 is 0.988,which means that with this peak intensity ratio,the accuracy rate of identifying EGC is 98.8%,and the corresponding sensitivity and specificity are 93.9% and 91.9%,respectively.3.The average in vivo Raman spectrum of normal tissues and diseased tissues,including HGIN and intramucosal cancer,from stomach of patients with EGC: 1)There are differences between the shape of the average Raman spectrum and some material assignments of Raman peaks of the two groups: Significant Raman peaks corresponding to the normal tissues appear at 822 cm-1?863 cm-1?950 cm-1?990 cm-1?1087 cm-1?1103 cm-1?1171 cm-1?1206 cm-1 ? 1321 cm-1 ? 1515 cm-1 ? 1645 cm-1.By contrast,significant Raman peaks corresponding to the diseased tissues were observed in the Raman spectra at 820 cm-1?860 cm-1?952 cm-1?987 cm-1?1089 cm-1?1100 cm-1?1169 cm-1?1208 cm-1?1323 cm-1?1517 cm-1?1646 cm-1;Characteristic peaks appeare at 847 cm-1?877 cm-1?886 cm-1?898 cm-1?911 cm-1?930 cm-1?974 cm-1?996 cm-1?1152 cm-1?1180 cm-1?1226 cm-1?1588 cm-1 in the average Raman spectrum of the diseased tissues.2)There are statistical differences between the the integral energy ratio of the two groups: The AUC of the integral energy ratio in the non-continuous frequency band(E1500—1600 cm-1/E1050—1150 cm-1)is 0.976,which means that with this non-continuous frequency band,the accuracy rate of identifying EGC is 97.6%,and the corresponding sensitivity and specificity are 94.4% and 93.7%,respectively;The AUC of the integral energy ratio in the continuous frequency band(E1350—1500 cm-1/E1200—1350 cm-1)is 0.983,which means that with this continuous frequency band,the accuracy rate of identifying EGC is 98.3%,and the corresponding sensitivity and specificity are 94.4% and 93.7%,respectively;The AUC of the integral energy ratio in the continuous frequency band(E1200—1600 cm-1/E800—1200 cm-1)is 0.986,which means that with this peak intensity ratio,the accuracy rate of identifying EGC is 98.6%,and the corresponding sensitivity and specificity are 94.4% and 100.0%,respectively.4.The average in vitro Raman spectrum of nonlesional tissues and diseased tissues,including HGIN and early squamous cell carcinoma,from esophagus of patients with early esophageal cancer: 1)There are differences between the shape of the average Raman spectrum and some material assignments of Raman peaks of the two groups: Significant Raman peaks corresponding to the nonlesional tissues appear at 818 cm-1?918 cm-1?963 cm-1?975 cm-1?1171 cm-1?1210 cm-1?1298 cm-1?1309 cm-1?1416 cm-1?1486 cm-1?1538 cm-1?1560 cm-1?1640 cm-1?1678 cm-1?1734 cm-1.By contrast,significant Raman peaks corresponding to the diseased tissues were observed in the Raman spectra at 820 cm-1?920 cm-1?961 cm-1?970 cm-1?1173 cm-1?1209 cm-1?1299 cm-1?1308 cm-1?1418 cm-1?1488 cm-1?1540 cm-1?1563 cm-1?1641 cm-1?1676 cm-1?1737 cm-1;Characteristic peaks appeare at 1025 cm-1?1608 cm-1?1684 cm-1 in the average Raman spectrum of the diseased tissues.2)There are statistical differences between the the integral energy ratio of the two groups: The AUC of the integral energy ratio in the non-continuous frequency band(E1400—1550 cm-1/E1120—1270 cm-1)is 0.991,which means that with this non-continuous frequency band,the accuracy rate of identifying EGC is 99.1%,and the corresponding sensitivity and specificity are 97.0% and100.0%,respectively.Conclusions:1.Raman spectroscopy can distinguish early esophageal and gastric cancer tissues from non-lesional tissues with ESD specimens in vitro,and has high accuracy,sensitivity and specificity;2.Raman spectroscopy can distinguish early gastric cancer tissues from non-lesional tissues in vivo,and has high accuracy,sensitivity and specificity.In particular,the diagnostic effect of continuous frequency band(E1200cm-1—1600cm-1 / E800cm-1—1200cm-1)is more excellent than that of non-continuous frequency band(E1500cm-1—1600cm-1 / E1050cm-1—1150cm-1)and continuous frequency band(E1350cm-1— 1500cm-1 / E1200cm-1—1350cm-1). |
PDF Full Text Request