To Investigate The Role Of P16and The Cell Block Technique In The Treatment Of Cervical Intraepithelial Neoplasia

Background:Cervical cancer is the most commonly known gynecologic malignant tumor in China, which threats the life and health of Chinese women seriously. The persistent infection of the human papillomavirus (human papilloma virus, HPV) is the main cuase of cervical cancer, and more than99%of cervical cancers are caused by high risk HPV infection. It usually takes8-12years for the normal cervical infection of high risk type HPV virus to gradually progress into cervical cancer. Cervical intraepithelial neoplasia (CIN) is the precancer pathological change in the long development process of cervical carcinoma. Timely detection of CIN and appropriate treatment is the important means to prevent the occurrence of cervical cancer and to reduce the mortality of cervical cancer. Cervical intraepithelial neoplasia is usually divided into three levels according to different light cell atypia and different degree of involvement of the cervical epithelial layer, ranging:CIN1, CIN2, and CIN3. About57-60%of CIN1will naturally regress, while only33%of CIN3will possibily degrade. The chance of CIN3to progress into invasive cancer in1year is about0.2%. So it is considered as the real precancer lesion Typically, CIN2is thought to be high grade intraepithelial neoplasia, like CIN3, that needs to be treated actively through operation. But the natral biological behavior of CIN2is more close to CIN1. At present, there are two typical therapy methods for biopsy-confirmed CIN2-3:cold knife conization and loop electrosurgical excisional procedure (LEEP). Both are effective in the treatment of cervical intraepithelial neoplasia, but will bring some side effects. The incidence of perinatal complications, risk of serious premature delivery and having a low weight infant was significantly higher than that in general population.It will cause excessive treatment for many CIN2-3patients proven through colposcopy-guided biopsy, if they are all given operation without screening. So how to use appropriate means to screen out high-risk CIN2-3to give targeted operation is of vital significance for reducing excessive treatment, especially those over treatment of young patients with birth demand. This study intends to explore an effective method to shunt patients of high-grade cervical intraepithelial neoplasia, thereby reducing the chance of excessive treatment on those patients with low risk of progressing into invasive cervical carcinoma.Part one:Study on the conization pathology negative phenomena of biopsy confirmed CIN2-3patients. Objective:To assess the influnce of the interval time between cervical conization and biopsy on the negative rate of conization pathological. And to search for the risk factors of conization pathology negative phenomena through the correlation between the negative rate and other possible affecting factors, such as age, so as to reduce the occurrence of excessive treatment. Methods:391cases of the CIN2-3patients confirmed by colposcopy biopsy pathology and treated with LEEP have been analyzed retrospectively. After collecting the detailed clinical data, such as the interval time between biopsy and LEEP, and the age of every object of study, the researcher used statistical method to analyze the relationship between these factor and post-conization pathology classification. Results:1, The ratio of discovering conization pathology negative is26.9%(105/391) when we consider the pathological results of1patients with≤CIN1as conization pathology negative;2, With the increase of interval time between cervical biopsy and LEEP operation, conization pathology negative ratio increased significantly, Pearson correlation coefficient is5.44(P=0.020) single factor logistic regression, OR:1.374,95%CI:1.089-1.735, P=0.008;3, It was found through the comparative study of biopsy in two groups of patients that all other affecting factors, including contraceptive method, cytological results, HPV (the number of classification, quantitative and high risk HPV type), and colposcopy results, were not statistically significant. Only biopsy pathology grade and age are closely related to the negative rate (P<0.002, P=0.015);4, It is found through the multi factor Logistic regression analysis, biopsy pathological grade (P=0.001), age (P=0.039) and the interval between biopsy and cone (P=0.028) is closely related to conization pathology negative. Conclusion:1. Having a≤CIN1LEEP specimen was significantly associated with the type of the preceding biopsy (p=0.001), age (p=0.039), and the time interval (p=0.028).2.The probability of having a≤CIN1LEEP specimen was substantially elevated among young women whose preceding cervical biopsy suggested a low-grade abnormality with a long biopsy-LEEP interval.Part Ⅱ The relationship between the expression of P16in the cervical biopsy confirmed CIN2and the post-conization pathology classification Objective:To explore the relationship between the expression of P16in the cervical biopsy confirmed CIN2and the post-conization pathology classification, in order to speculate on whether it can be used to shunt cervical biopsy confirmed CIN2patients. Methods:Making retrospective analysis of128cases of CIN2patients who were taken as researching objects, and using immunohistochemistry to detect the expression of P16in the paraffin sections of those patients’ colposcopy biopsy tissue. Results:1.The rate of detected positive P16in115cases of CIN2biopsy specimens was87.8%(101/115);2. Among the patients whose P16staining of cervical biopsy specimens is less than or equals to,48.3%of their postoperative pathologic grading after LEEP is less than or equals to CIN1, while those patients whose P16staining of biopsy specimens is+++,34.9%of their postoperative pathological level is less than or equals to CIN1. Compared with the patients whose P16staining of cervical biopsy specimens is less than or equal to++, those patients whose P16staining of biopsy specimens is+++have lower occurrence rate of negative cervical conization pathology, but the difference was not statistically significant (P=0.203). Conclusion: The phenomena of negative conization is more likely to occur when the score of P16immunohistochemical staining of biopsy specimens is<3, suggesting that p16INK4a may help to predict the prognosis of patients with CIN2. But the difference was not statistically significant, perhaps because the study has excluded the inconsistent case for biopsy pathological diagnosis and thus reduced the excessive diagnosis of benign cases.Part Ⅲ The relationship between the expression of P16in preoperative liquid based cell wax block and post-conization pathology classification. Objective:to detect the expression of P16in the liquid based cell paraffin embedded tissue of cervical biopsy confirmed CIN patients before operation, and then to investigate its relationship with postoperative pathology and outcome through two years follow-up, to finnally evaluate its prognostic value in the individualized treatment of CIN. Methods:Fistly, the researcher selected those patients whose TCT are above ASCUS, and having been confirmed of CIN2-3level after receiving colposcopy biopsy within1month and eventually accepted cervical LEEP or cold knife conization. A patients were given two years follow-up. Secondly, we took the remaining tissue cells in the TCT preservation solution to make cervical cell block, meanwhile employed immunohistochemistry to detect the expression of P16on the cell block. Results:1. Compared with cytological smear, the morphological structure of cells in paraffin sections is similar to that of tissue sections, in addtion, it is more convenient, and easy to preserve;2. Compared with the patients whose P16staining of cervical cell block specimens is less than or equals to+, those patients whose P16staining of cell block specimens is++or+++have lower occurrence rate of negative cervical conization pathology, and the difference has statistical significance.3.Taking the positive expression as the criterion, the sensitivity, specificity, positive predictive value, and negative predictive value of positive cervical conization pathology were91.0%,36.8%70.1%and71.4%accordingly. Conclusion:using cell block is conducive to do retrospective analysis and follow-up of patients; Based on the results of P16immumohistochemical staining in cervical exfoliated cells block, it is feasible to shunt and supervise CIN patients, to predict the risk of cervical cancer, and eventually to reduce the occurrence of excessive treatment.