The HPV virus is a small, non-encapsulated double helix DNA virus surrounded by a capsid. It is a common health problem all over the world. Every year, 80 million people in the world are infected with the HPV virus. It causes genital warts in thirty million people and cervical cancer in five hundred thousand people every year. A woman has an 80% chance of being infected with HPV by the age of 45. HPV is most commonly encountered between the ages of 20-30. After the first sexual intercourse, 40% of women are infected with HPV within 2 years and 60% within 4 years. There are more than 500 thousand HPV positive women in Turkey. It is a serious health problem in our country. For this reason, the Ministry of Health conducts HPV screening in the national screening program.
The virus has more than 200 types. The number at the end of the word HPV refers to the type number. 60 different types of HPV virus infect the skin and 40 different types infect the female and male genitals. The HPV virus is mainly responsible for cervical cancer, anal cancer, penile cancer and vulvar (external genitalia) cancer. DNA of the HPV virus is found in 99% of cervical cancers. Apart from cancer, HPV causes serious health problems by causing warts (condyloma) on the hands, feet, larynx, anus, penis, vulva and vagina. HPV types 6 and 11 are the most common types causing genital warts. Other types 16,18,31,33,35,39, 45,51,52,56,58,59 are responsible for cervical cancer. Among the cancer-causing types, 16 and 18 are very high-risk types. In studies conducted in our country, unlike abroad, types 31, 33 and 45 were also frequently found in cervical cancer precursors.
How is HPV transmitted?
HPV is most commonly transmitted through sexual intercourse. It can also be transmitted through poorly cleaned medical instruments, shared underwear and hygiene products.
How does HPV cause disease?
The HPV virus most commonly enters the body through micro cracks that occur after sexual intercourse. It enters the cells of the vagina and cervix. In 90% of patients, HPV is cleared from the body within a year after infection. In patients who smoke, have a weak immune system, have many sexual partners, have unprotected sexual intercourse (not using condoms), the virus cannot be cleared from the body or re-infected. In some cases, the virus remains latent in the body and cannot be detected by tests. It can return to its active form after a weakened immune system or a severe illness. The longer the virus remains active in the body, the more likely it is to develop cancer. Permanent immunity cannot be achieved by natural elimination of the virus. HPV vaccines are required for permanent immunity (detailed in the Vaccines section).
What is CIN (precancerous lesions of the cervix)?
Once inside the cell, the virus travels to the nucleus and leads the cell to uncontrolled reproduction. If the virus cannot be eliminated from the body, it causes cell degeneration. This deterioration is called dysplasia. As a result of this condition called dysplasia, CIN (cervical intraepithelial neoplasia) lesions are formed. These lesions are precancerous lesions. CIN lesions are divided into three categories: mild, moderate and severe. They are named as CIN1, 2, 3. CIN 1 lesions regress within 2 years with 90% probability. Therefore, cervical shaving (LEEP or conization surgery) or removal of the uterus is not necessary in CIN 1 lesions. CIN 2 progresses to cancer in 5-10% and CIN 3 in 12-40%. CIN2-3 lesions should therefore be treated. CIN 2 and 3 are treated in the same way. In the first step, cervical shaving surgery is performed. The follow-up and treatment method should be determined according to the pathology result (LEEP or conization is explained in the other section).
The presence of CIN lesions is not decided by smear. The treatment method can be determined after evaluation with colposcopy (colposcopy is explained in the other section) and biopsy. Surgery cannot be decided according to the smear result.