When it comes to cancer, perhaps many people think that once you have it, it is a dead end. Indeed, this is true for many malignant tumors, such as ovarian cancer and liver cancer, where the organs are deeply hidden in the abdominal cavity, and even if a malignant tumor occurs, it is often not felt in the early stage and cannot be detected in time. When the tumor is discovered, the patient often has a belly full of ascites, or when it causes bloating and pain, the tumor is often already huge at that time. Therefore, once these tumors are discovered, they are often advanced, and as a doctor, even if you are highly skilled in medicine, you cannot save the patient’s life. This is also true for malignant tumors in other parts of the body. But cervical cancer, it is different. Cervical cancer used to be the most common malignant tumor affecting women, and it is the most common malignant tumor after ovarian cancer among reproductive tract tumors, with a 1 in 128 chance of occurring in a woman’s lifetime. Unlike the ovaries, the cervix is located closer to the outside of the body, so it is very easy for the doctor to expose the cervix when the speculum is opened to the vagina during the examination, thus providing a great convenience for the prevention of cervical cancer. Back in the 1820s, a Greek medical doctor, Papanikolaou, invented the method of obtaining cells from the cervix for tumor screening, known as the Pap Smear. Each time a doctor performs a physical examination, he or she uses a small wooden plate to gently scrape the cervix (no pain!). The cells taken off are examined under a microscope to see if there are any tumor cells that are different from normal cells (Figure 1). It was this great invention that changed the way cervical cancer was screened. We know that malignant tumor starts from the malignant transformation of a single cell, the cells of malignant tumor become two, two become four, and gradually grow up, and it often takes several years or even longer to grow up to a tumor as big as a fist. If the tumor can be detected by cervical smear before it grows very big and treated in time, then cervical cancer can be cured. Nowadays, in developed countries, women are very aware of regular medical checkups, and many early tumors that become malignant are detected and treated in time, and advanced cervical cancer that grows like a cauliflower and festering is no longer common (Figure 2). The prognosis of malignant tumors may be very different between early and late treatment, and most of the early stage tumors are completely curable, so the overall mortality rate of cervical cancer is greatly reduced. In contrast, the ovaries, because of their deeper location, are far less susceptible to early detection and prevention than cervical cancer. Nowadays, with the development of technology, the traditional cervical smear has been replaced by new and better methods, which allow doctors to use a brush to take cells from the cervix and improve the sensitivity and accuracy of the test through thin-layer smears and computer-assisted methods, such as TCT, CCT or LCT, which are usually used in outpatient clinics, but the principles are similar. If these new technologies are not available in some underdeveloped areas, even the traditional cervical smear method can be used to prevent cervical cancer. The key is not the technology of detection, but the awareness of regular checkups is more important. Figure 3: Technical differences between traditional smear and thin layer smear Therefore, one of the key points in cervical cancer prevention is to enhance regular medical checkups to detect and treat tumors at an early stage. Early stage cervical cancer often does not have any uncomfortable symptoms and cannot be detected by the appearance of the cervix alone; it must be detected by cellular level examination. When the tumor develops to an advanced stage, there may be bleeding after sex, increased leucorrhea, pain, and even involvement of surrounding organs, and the effect of treating the tumor at an advanced stage is relatively much worse. Another condition that needs to be understood about cervical cancer is its etiology. In medical textbooks, it was once thought that cervical cancer was related to many factors, such as multiple sexual partners, early sex, smoking, etc. However, later studies found that these factors were all floating around and the real killer of cervical cancer was actually a virus called Human Papilloma virus (HPV for short). By the way, about 90% of cervical cancers are squamous cancers, and squamous cancers are closely related to cervical cancer, while the rare adenocarcinoma is not as close as squamous cancers. Scientists have found that a special part of the cervix (squamous junction) is the site of HPV infection. If a person has immunity problems and cannot clear HPV after infection, resulting in persistent HPV infection, then it will easily lead to cervical cancer. These people are more likely to develop cervical cancer than those who do not have persistent HPV infection. There are more than 60 subtypes of HPV, but the main ones that cause cervical cancer are subtypes 16, 18, 31, 33, and others that cause vulvar or vaginal acromegaly. Therefore further research has found that testing for such HPV infections is of some interest. Testing for HPV helps to understand who is prone to develop cervical cancer more than others. However, HPV infection in women is also very common and cannot be prevented. HPV is not just transmitted through sexual intercourse, but close contact can lead to HPV infection in women, so the chance of HPV infection in a woman’s lifetime exists. HPV infection is not detected in a single test, so currently some organizations such as NCCN (American Cancer Assistance Network) and ACOG (American College of Obstetrics and Gynecology) recommend screening for cervical HPV infection after the age of 30, and HPV detected before the age of 30 does not require special treatment. If HPV is found to be positive, then the patient needs to be told that it is a high-risk status and needs to be monitored more intensively for cervical cancer. If annual monitoring is done and both HPV and cervical smear are negative for 3 consecutive years, then the interval of testing can be extended later and can be transitioned to every 3 years. Screening with a pap smear is recommended before the age of 30 if sexual intercourse has begun, but HPV testing is not necessary; a pap smear is a screening test whose results are usually described cytologically, and if a pap smear reveals a problem, the doctor may perform further colposcopy and cervical biopsy as needed to further understand whether cervical cancer or precancerous lesions The presence of cervical cancer or precancerous lesions. Currently, there is no specific drug for HPV treatment, so the recommendation is to “treat the disease but not the virus”, i.e. if there is a cytological problem, investigate and treat it, but if there is only HPV infection and no cytological abnormality, monitor the disease and do not need to do any treatment for HPV. Another notable advance is the vaccine for cervical cancer. As mentioned earlier, with the understanding of the causes of cervical cancer, then for these viruses, scientists have developed vaccines for high-risk HPV types, which can be injected to produce antibodies to avoid HPV infection and thus reduce the incidence of cervical cancer. The HPV vaccine is currently available in several countries and is mainly for adolescent women who have not yet dissolved their sexual life. Once they start having sex, HPV infection is common and the HPV vaccine is not very meaningful. The currently approved indications are for women aged 16-26. The HPV vaccine is currently available in Hong Kong and Taiwan, but the HPV vaccine is still not available on the mainland because of the State Drug Administration’s approval process, and it is theoretically illegal to use the HPV vaccine on the mainland. The domestic vaccine is also under development, and hopefully, it will be available one day sooner to benefit the majority of women.