LIU FANG ^1* Bo Cao ^1* dan Su ²

• ¹ The First Affiliated Hospital, Guizhou University of Traditional Chinese Medicine, Guiyang, China
• ² The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, China

Aims:By studying the cross-population characteristics of tongue image and tongue coating microorganisms during the evolution of colorectal cancer, the differences of tongue image characteristics and tongue coating microorganisms among different populations were further evaluated, providing references for early screening,diagnosis and treatment of colorectal cancer. Methods:The tongue image features of the subjects were collected by DS01-B tongue surface information collection system, mainly including tongue quality and tongue coating, and the tongue image was quantitatively analyzed by color space Lab value.The microbial characteristics of tongue coating were detected by high-throughput sequencing (16SrRNA amplicon sequencing).All subjects came from the patients in the Sixth Affiliated Hospital of Sun Yat-sen University and recruited volunteers. Results: A total of 377 subjects were recruited in this study, including 56 healthy subjects, 65 colorectal adenomas and 256 colorectal cancer patients. The results showed that: in terms of texture of fur, the "thick fur" was a significant statistical difference (P <0.05) in the 3 groups. In addition, there was also a statistical difference in "greasy fur" and "peeled fur" among the 3 groups (P <0.05).Lab quantitative analysis of tongue color and fur color: The results showed that the L value of tongue color in healthy group was significantly different from that in CRA group and CRC group (P < 0.01), but there was no significant difference between CRA group and CRC group (P >0.05). Tongue coating microorganisms, there was no significant difference in the richness and diversity of the three groups of subjects (p >0.05). There were 296 species in the three groups, accounting for 44.65%, and the species in colorectal cancer population was the most, reaching 502.From the differences in community composition among the three groups, it was found that there were certain differences in bacterial community composition between healthy people, CRA and CRC, and the differences became more and more obvious with the development of the disease. Conclusions: This study revealed the specific cross-population tongue image characteristics and the specificity of tongue coating microorganisms in the evolution of CRC, providing new research ideas for early screening, early diagnosis, mechanism exploration, prevention and treatment of colorectal cancer.