There are two possible strategies to prevent tumours: the first is to prevent the disease from forming by adopting a healthy lifestyle and moderate sexual activity (primary prevention), and the second is to diagnose the disease as early as possible, before it manifests itself on a clinical level (secondary prevention). A screening test is a test that allows for the identification of a certain disease, specifically tumors, in asymptomatic people at an early stage. In an organized screening program, the health company directly invites the entire segment of the population deemed at risk of developing a certain disease to participate, offering the test and any further information free of charge.
Cancer of the uterine cervix (or cervix) is the third most frequent cancer among women, after breast and colorectal cancer. The human papilloma virus (HPV) is the main cause of the onset of cervical cancer. The disease affects the cervix, which is the segment that connects the body of the uterus with the vagina. The lining of the uterine cervix is composed of two cell types: squamous and glandular, which consequently can give rise to two different cancers (squamous cell carcinoma and adenocarcinoma). The two areas converge in one area, the transition area, from which most cancers originate (85 percent of diagnoses).
Compared to other cancers cervical cancer has the advantage of being easily preventable and treatable if detected early. In fact, in many cases it is possible to intercept initial forms of transformation of the mucosa and carry out secondary prevention by removing the precancerous lesions. To prevent HPV infection, since 2008 in Italy a campaign has been put in motion that recommends and offers free vaccination against the virus to girls between 11 and 12 years of age, when it is assumed that they have not yet engaged in sexual intercourse and therefore not come into contact with the virus.
The most common are two vaccines that are administered intramuscularly: one bivalent and one quadrivalent. The first is directed against strains 16 and 18 of the virus, capable of causing precancerous lesions and responsible for 70 percent of cervical cancers, while the second one is also directed against strains 6 and 11, responsible for the formation of genital warts.
Since 2017, a third vaccine has been developed called 9-valent, which in addition to HPV 6, 11, 16 and 18, ensures protection against five other serotypes capable of inducing cancer..
At first, the vaccination was divided into three doses administered over a period of six months, while today it has been shown that in 11-12 year old girls even two doses guarantee sufficient protection. For vaccinations at a later age, however, three are still recommended.
Given their relatively recent introduction, the duration of the protection conferred by vaccines is not yet known with absolute certainty. Based on observations so far, it appears to extend to at least ten years, but subsequent booster doses may need to be added in the future to enhance the effect.
People who have been vaccinated must also undergo regular screening for cervical cancer from the age of 25.In fact, the HPV vaccine only offers protection from some of the more dangerous strains of the virus and not from others which, although rare, may cause cellular lesions in the cervix. The use of condoms is not enough to protect against infection, but it must always be recommended, even to vaccinated people, not only to avoid unwanted pregnancies but also to protect against a large number of sexually transmitted infections.
The 2017-2019 National Vaccine Prevention Plan also extends vaccination to males in their eleventh year of age, both to interrupt the circulation of the virus and to protect them from tumors rarer than that of the uterus but dependent on the same viral strains, such as carcinomas of the anus, penis, oral cavity and throat.
The high level of protection offered by the vaccine may falter against strains that the body may have already encountered. This is why vaccination is recommended and offered free of charge for ages 11-12, in which boys and girls have not yet initiated sexual activity, the main vehicle for the transmission of the virus. For any vaccinations at a later age, the vaccine is approved by the European Medicines Agency (EMA) and offered in some Italian regions at a discounted price up to 26 years of age, since it can still prevent infections of viral strains not yet encountered by people.
The test used in screening for cervical cancer is the Pap test, which must be carried out by all women between the ages of 25 and 64, every three years. According to the scientific evidence available, this is in fact the time interval that maximizes the benefits of screening. The Pap test consists of a sample of a small amount of cells from the cervix, performed by rubbing a spatula and a swab on its walls. The cells are taken, and after undergoing a specific chemical process, they are analysed under a microscope to inspect the presence of alterations, which may indicate a possible transition into cancer cells. If the Pap test does not show any abnormalities, the woman is asked to repeat the examination after three years. If the Pap test results positive - that is, in cases where microscopic analysis reveals the presence of cells with pre-tumor or tumor-like characteristics, the cervical cancer screening protocol calls for in-depth exams. The woman is invited to carry out a test for the detection of the HPV virus, and, in the case of recurring positivity, will be invited to undergo a colposcopy.
Colposcopy is an examination that allows an enlarged view of the uterine cervix. In this way, the doctor is able to confirm the presence of pre-tumor or tumor lesions and evaluate the extent of the damage. Colposcopy may be followed by a biopsy, or a sample of a small portion of abnormal tissue to be subjected to an analysis that definitively confirms the exact characteristics of the suspected lesion.