Real-time Optical Diagnosis Of Gastric Cancer With Serosal Invasion Using Multiphoton Imaging

Background:Gastric cancer is one of the most common malignancies.The morbidity and mortality in China are the second highest among all types of cancers.About 80%of gastric cancer in China is advanced gastric cancer,and the 5-year survival rate is less than 40%.The depth of tumor invasion,T-stage,is a very important factor affecting its prognosis.In particular,whether the tumor penetrates the serosal layer plays an important role in the determination of the patient's treatment plan and the prognosis of the tumor.At present,the judgment of T staging of gastric cancer is mainly through ultrasound endoscopy and CT which accuracy rate is only 70%,and also cannot be achieved in real time and pathological diagnosis requirements.The real-time nature of multiphoton imaging and its "optical biopsy" characteristics suggest its wide application prospects in clinical research.Under the inevitable development trend of multiphoton equipment combined with endoscopy and endoscopy,we believe in multiphoton microscopy imaging technology can help us improve the accuracy rate of the diagnosis of gastric cancer T4 staging,guide the development of clinical treatment programs,and improve the survival rate of the patient.Objective:l.To establish diagnostic criteria for multiphoton imaging of gastric cancer with serosal involvement.2.To compare the sensitivity,specificity and accuracy of EUS and multiphoton microscopy in the diagnosis of T4 gastric cancer in blind.Methods:1.After the 20 gastric cancer samples were scanned by multiphoton imaging,the serosal sections were selected for sequential HE and Masson staining.Three images were used to obtain the standard multiphoton imaging of whether the gastric mucosa was affected.2.The diagnosis of T stage for gastric cancer was performed by ultrasound endoscopy and multiphoton microscopy,respectively and"blinded".Compare two kinds of optical diagnosis and HE diagnosis after"unblinded",calculate diagnostic sensitivity,specificity and accuracy of ultrasound endoscopy and multiphoton microscopy.Results:1.Through 20 patients research,multiphoton microscopy imaging diagnostic criteria of gastric cancer with or without serosal invasion was established.Optical diagnostic features of gastric cancer without serosal invasion:two-photon excited fluorescence(TPEF)signals:(1).Regularly distributed elastic fibers,(2).No cellular and nuclear pleomorphism;Second harmonic generation(SHG)signal:(1).Regular collagen structure,(2).Correlation value of 0.21 ±0.05,(3).collagen content of 0.79±0.16.When gastric cancer invades the serosal layer,TPEF signal:(1).Cellular and nuclear pleomorphism,(2).Irregular tubular structures,(3).Cancer cells characterized by irregular size and shape,enlarged nucleus,and increased nuclear-cytoplasmic ratio.SHG signal:(1).Irregular collagen structure,(2).Correlation value of 0.69±0.18,(3).Collagen significantly decreased,collagen content of 0.36±0.18.We compared the two groups of data,paired t-test P values were less than 0.001,the difference was statistically significant.2.Through 60 patients research:the sensitivity of endoscopic ultrasonography in the diagnosis of T4 stage gastric cancer was 70%(21/30),the specificity was 66.67%(20/30),the accuracy was 68.33%(41/60),and the positive predictive value was 67.74%(21/31),the negative predictive value was 68.97%(20/29);the sensitivity of multiphoton microscopy in the diagnosis of T4 stage gastric cancer was 90%(27/30),and the specificity was 96.67%(29/30).The accuracy was 93.33%(56/60),the positive predictive value was 96.43%(27/28),and the negative predictive value was 90.63%(29/32).We compared thetwo groups of data,?2 test P values were less than 0.05,the difference was statistically significant.Conclusion:1.Multiphoton microscopy imaging is a technology that stimulating autofluorescence substances inside gastric serous membrane and second harmonic generation signal from collagen,produce two-photon fluorescence effect,can realize"optical biopsy" of gastric cancer with or without serosal invasion,consistent with HE diagnosis.2.The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of multiphoton microscopy in the evaluation of T4 stage gastric cancer were superior to those of ultrasound endoscopy,which can significantly improve the accuracy of diagnosis of T4 gastric cancer.