Cervical cancer is not carcinoma in situ, and carcinoma in situ is not cervical cancer. In the diagnosis of carcinoma in situ, if the abnormally proliferating cells reach or exceed 2/3 of the basement membrane, but do not break through the basement membrane, then it can be diagnosed as carcinoma in situ. Moreover, the diagnosis of carcinoma in situ has been abandoned in the current diagnostic standard, and the corresponding diagnostic standard is high-grade intraepithelial neoplasia. If the grade of intraepithelial neoplasia is II-III, it is a high-grade intraepithelial neoplasia, and the diagnosis of carcinoma in situ is no longer mentioned, but cervical cancer is diagnosed as cervical cancer when the atypical proliferating cells and abnormal proliferating cells break through the basement membrane.