Cervical cancer is the third most common malignancy among women worldwide after breast and colorectal cancer, the second most common malignancy after breast cancer in developing countries, and the most common malignancy of the female reproductive tract. in 2008, there were an estimated 529,800 new cases of cervical cancer and 255,100 deaths worldwide, of which 85% of new cases were in developing countries (Jemal 2011). With the introduction of cervical cancer screening, the incidence and mortality rates of cervical cancer in developed countries have decreased significantly. There are obvious regional differences in the incidence of cervical cancer, and the distribution of cervical cancer in China is mainly in the central region, with rural areas higher than urban areas and mountainous areas higher than plains, with high incidence areas in Jiangxi Tonggu, Hubei Wufeng, and Shaanxi Loyang. Diagnosis After typical symptoms and signs appear, cervical cancer is usually infiltrating cancer, so there is no difficulty in diagnosis, and biopsy can confirm the diagnosis. Early stage cervical cancer is often asymptomatic and the physical signs are not obvious, and the diagnosis needs to be confirmed by third-step diagnosis. Colposcopy The second step is colposcopy. For those with suspicious or positive cervical scraping cytology but no obvious cancer foci can be seen with naked eyes, colposcopy can magnify the lesion 6 to 40 times and directly observe the subtle morphological changes of cervical epithelium and blood vessels under strong light source. Colposcopy is performed simultaneously with vinegar white test and iodine test to determine the biopsy site according to what is seen to improve the correct rate of biopsy. 1. Vinegar white test: After 3% acetic acid is applied to the cervix, changes in the cervical epithelium and blood vessels are observed and the site of biopsy is determined according to the vinegar white epithelium. 2.Iodine test: Normal cervical and vaginal squamous epithelium contains glycogen and can be dyed brown by iodine solution, while cervical canal columnar epithelium and abnormal squamous epithelium such as cervicitis, squamous epithelial metaplasia, cervical precancer and cervical cancer are not colored without the presence of glycogen. This test is not specific for cancer, but cervical biopsy in the uncolored area can improve the accuracy rate of cervical precancer and cervical cancer, and can also understand the extent of cancer spread to the fornix. The commonly used iodine solution is Schiller or Lugol solution. The diagnostic accuracy of colposcopic multi-point biopsy can reach about 98%. However, this method is neither a substitute for cervical smear cytology or biopsy, nor can it detect lesions in the cervical canal. Differential diagnosis 1. Cervical erosion and cervical polyp may show contact bleeding and increased leucorrhea, which are sometimes difficult to distinguish from CIN or cervical cancer in appearance, and cervical scraping or biopsy should be done for pathological examination. 2. If there is infection and necrosis on the surface of submucosal fibroids of uterus, sometimes it can be misdiagnosed as cervical cancer. However, the fibroids are mostly round and come from the cervix or uterine cavity, often with a tip, and the normal cervix can be seen to encircle the fibroids. Other rare lesions of the cervix such as cervical tuberculosis, cervical papilloma during pregnancy, cervical warts, etc. are also easily misdiagnosed as cervical cancer and need to be differentiated by cervical biopsy.