The role of human papillomavirus in the occurrence and development of cervical cancer

Obstetrician-gynecologist, doctor of the highest category "ON CLINIC" Maria Georgievna Mavropulo

General information about the human papillomavirus

Molecular biological studies have proven that the presence of this virus in women is the most important factor in cervical carcinogenesis. HPV is a DNA-containing virus, the general type of host of which is vertebrates and humans. Virus replication occurs in the cell nucleus, the peculiarity of the virus is that it infects the basal layer of the epithelium. The epithelium is divided into three layers: basal, intermediate and superficial. HPV is able to reach the basal layer bordering muscle tissue and blood vessels. It can be there for a long time and disrupt cell division. The life cycle of this virus occurs only inside cells.

HPV is divided into several groups:

• The first type is safe, that is, non-oncogenic viruses (types 1-5, 10, 28, 49).
• The second type is oncogenic with low risk (types 6, 11, 13, 32, 34, 40, 41, 42, 43, 44, 51, 72).
• The third type is viruses with high oncogenic risk, which can lead to malignant mutations (types 16, 18, 26, 30, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 65, 66 and 68).

The main way of transmitting the virus is sexually.

HPV can also be transmitted:

• during childbirth from mother to child;
• household (i.e. the virus can remain in the external environment for some time and penetrate the body through damage to the skin);
• self-infection, namely, transfer from area to area of the body during epilation or shaving.

As for pointed condylomas, these are papillary formations that can be located anywhere, especially often on the mucous membranes of the vagina and cervix, in the anus, and the opening of the urethra. They range in color from flesh-colored to bright pink and red-pink. They have the shape of combs, semolina, or bunches of cauliflower. The presence of condylomas also depends on immunity, since viruses can remain undetected for a long time. There are situations when a sexual partner develops condylomas quickly, while a female partner develops them much later.

The incubation period for the virus is long - from several days to six months, it is sometimes present in a latent form, but due to some factors, an exacerbation of this virus, its active replication, may occur. Therefore, condylomas can sometimes regress (disappear) on their own.

You can be a carrier of the virus and not know it.

The percentage of people who are carriers of HPV is very high. Different publications indicate a different number of types of the virus that currently exist (from 140 to 600). Two types of the virus that affect cervical carcinogenesis have been reliably identified - types 16 and 18. Viruses of types 6 and 11 cause the appearance of genital warts.

Diagnostics of the human papillomavirus

Timely diagnosis is very important, since without the papillomavirus there is no cervical cancer. And in the presence of papilloma, not everyone gets cervical cancer - only thanks to timely detection and the right approach to treatment.

As for detection methods, this is, first of all, a colposcopic examination.

1. Colposcopy is an early method for diagnosing cervical diseases. It is an examination of epithelial tissue under a microscope using specialized tests that evaluate the reaction of the tested tissues to the effects of certain chemicals. Signs of HPV that can be seen during a colposcopic examination are acetowhite epithelium, "mosaic", white growths, pearl coloration when the cervix is treated with acetic acid (atypical transformation zone).

2. Cytological examination - forms the basis of programs aimed at early detection of cervical cancer, its screening. All women should undergo cytological examination, because with its help we can evaluate the properties of the epithelium. It is necessary that the smear be taken from the entire epithelial cover of the cervix, especially the junction of the stratified squamous and columnar epithelium, because 90% of tumors appear in this area. It is important for women to know that the analysis should be taken 5 days before or 5 days after menstruation, i.e. there should be no bloody discharge. Also, you should refrain from sexual intercourse for 48 hours, do not use vaginal ointments, suppositories or tablets. Sometimes it happens that patients want to undergo a cytological examination after an ultrasound, which is wrong, since the gel should not be used before taking a cytological smear of the cervix. Patients must be told about this so that the result is correct and accurate.

3. Polymerase chain reaction (PCR) is the next diagnostic method, which not only detects the presence of the papilloma virus, but can determine its type and quantity.

4. HPV DNA testing, namely the Daigen test is a highly specific and very accurate method, because it quickly identifies the clinical significance of the virus concentration. It is used as a screening for cervical cancer in women over 30 years of age. It is carried out in the following way: a special small brush is inserted into the cervical canal and rotated around its axis three times. Then it is placed in a special jar and sent for examination.

5. Cervical biopsy (check for malignancy) is another diagnostic option. After all, if you remember the stages of the disease, it can occur in a latent form, there may be clinical signs (growths on the skin). Subsequently, the DNA of the virus integrates into the DNA of the human cell, and only in this integral form is it possible for malignant changes to occur in the cell.

Human papillomavirus: treatment

Viruses are not treated, and there is no specific treatment for HPV. We are already treating the consequences of infection. We always recommend prevention:

• using condoms, although they cannot completely protect against the virus;
• reducing the number of sexual partners (but, again, you can get infected from one regular partner);
• treating inflammatory diseases, infections;
• sports;
• vaccination, which, by the way, is carried out at ON CLINIC.

Regarding vaccination, I would like to note that it is not a substitute for cervical screening, a 100% warning against HPV, and does not exempt from cytological studies.

Girls from 9 years old are subject to vaccination in some countries, from 12 to 15 years old in others, and sometimes up to 26 years old. It is believed that it is best to vaccinate against the virus in girls who have not yet started their sexual life, and they do not have identified forms of the papilloma virus. The cytological examination itself should be done annually, but the approach varies from country to country. Somewhere it is believed that it should be started after the first sexual contact, somewhere - from 21 to 25 years old and then undergo cytological screenings.

In our country, it is recommended to start cytological examinations at 21-25 years old

There is no need to undergo any preparatory examinations before vaccination, since it is produced by a non-living virus. This vaccine can be administered to all women, even those suffering from chronic diseases, cancer and immunodeficiency.

Why is HPV vaccination not included in the vaccination calendar?

Maybe because our health culture is not yet so developed. Women usually go to the gynecologist only when they have some complaints. There is no awareness that once a year it is necessary to go for a gynecological examination:

• ultrasound;
• examination;
• cytological examination.

This is not the case, therefore today we have a high level of cervical cancer and breast cancer.

We, doctors, in turn, try to convey to patients that it is necessary to vaccinate, and not only the women themselves visiting our center, but also the girls they have in their family. Early vaccination will not protect against HPV in general, because its types are very numerous, but it can protect against the papilloma virus with a high oncogenic risk (types 16, 18). I believe that vaccination also works on other types - 31, 33, 45. We have these vaccines in our clinic. These are Gardasil (quadrivalent) and Cervarix (bivalent).

Again, viruses are not curable. We can only treat the consequences of viruses:

• surgery;
• laser treatment;
• cryodestruction;
• immunomodulators;
• removal of condylomas;
• treatment with "Surgitron".

And the consequences are dysplastic changes in the cervix, namely dysplasia of the 1st, 2nd and 3rd degree.

Recommendations from "ON CLINIC"

I would like to give the following recommendations to all women:

• Undergo a mandatory examination with cytological screening of the cervix, visit a gynecologist not only when complaints appear, but annually.
• Be sure to undergo screening for cervical cancer after 30 years, because HPV can have a transient form, i.e. i.e. it can appear and illumine independently from the body.
• Until the age of 30, the approach to the virus should be special, and after 30 years the picture changes, and screening is mandatory, and it is better to do it in a comprehensive manner, using the Daigen test, PAP test and oncoprotein.
• Prevention should also be taken seriously, since treatment requires costs - both psychological and material.
• Conduct timely treatment when the papilloma virus and concomitant infections are detected.