Cervical cancer is the most common malignant formation of the female reproductive system worldwide; he is the second most common in women after breast cancer. It is more often found in women from 45 to 50 years, but it can also occur at a young age. The incidence is higher in developing countries. For example, in India, cervical cancer is the most common cause of death among women aged 35 to 45 years. In Russia, the incidence rate is approximately 11 cases per 100 000 population. Diagnosis of cervical cancer - the subject of the article.
Structure of morbidity
There are differences in the incidence of cervical cancer in different socio-economic groups within a single state. For example, in the US, black women are almost twice as likely to suffer from cervical cancer than white women, but this rather reflects their lower standard of living and inadequate access to health services than ethnic predisposition. In studies conducted in Scotland, similar results were obtained: among women with low incomes, the risk of cervical cancer increased threefold as compared to more affluent women.
Types of cervical cancer
Squamous cell carcinoma is the most common type of cervical cancer, accounting for more than 90% of cases. It affects the cells of the flat epithelium lining the cervix. However, at present, adenocarcinoma (a tumor from the secretory epithelium) is becoming more common. It is the stage of the disease, and not the cellular composition of the tumor, that determines the outcome of the disease for the patient.
Screening Value
In developed countries, the incidence of squamous cell carcinoma of the cervix has declined in recent years, due to early detection during screening and successful treatment of precancerous conditions. Screening is not as effective in detecting adenocarcinoma; perhaps this is one of the reasons for the relative increase in the number of cases of this disease. The pathology of the cervix can be detected during gynecological examination. The earlier the cancer is diagnosed, the higher the survival rate of the patient. The reasons for the development of cervical cancer have not been fully elucidated, however, its relationship to the human papillomavirus (HPV) has been reliably proven. There are more than 70 known types of this virus. Types 16,18, 31 and 33 are oncogenic (capable of causing malignant cell degeneration) and are associated with the development of cervical cancer.
Sexual Activity
Early onset of sexual activity, and frequent changes in sexual partners increase the risk of developing cervical cancer in the future. At electron microscopy the human papilloma virus has a characteristic appearance. Some of its types are associated with cervical cancer. In addition, his likelihood is higher if the patient's partner has multiple sexual relations with other women. It is believed that smoking is also associated with an increased risk of developing cervical cancer.
Immunosuppression
Women with reduced immunity have a higher risk of developing preinvasive cervical carcinoma (cervical intraepithelial neoplasia - CIN). Patients receiving drug-induced immunosuppression, for example, for kidney transplantation, are at increased risk. HIV infection, accompanied by suppression of the immune system, also increases the likelihood of developing the disease. It is known that cervical cancer is preceded by recognizable pre-invasive (precancerous) changes in the mucosa. At this stage, pathological foci in the superficial epithelium of the cervix have a specific localization at the site of the transition of the ectocervix (lining of the vaginal part of the cervix) into the cervical canal. These changes can be transformed into cancerous ones in the absence of treatment.
Early detection
Precancerous changes in the cervical epithelium and early stages of cancer, which occur asymptomatically, are revealed during the examination of a smear from the cervix during screening. The resulting cervical epithelial cells are sent to a cytological study (cell structure analysis). On this histological preparation, groups of cells of the cervical epithelium are visible. During screening, all cells are examined for pathological changes. When the pathological results of the cytological examination of the smear are obtained, the patient is referred for colposcopy.
Colposcopy
Colposcopy is a visual examination of the cervix and upper vagina with an endoscopic device. The technical possibilities of colposcopy allow you to examine the cervix under an increase and exclude the presence of visible neoplasms, erosions or ulcers on its surface. During the study, it is possible to produce tissue biopsies for analysis. With the help of a colposcope, you can illuminate the cervix and look at it under magnification in order to detect cancer changes at an early stage. To determine the prevalence of the tumor process, a bimanual (two-hand) vaginal or rectal examination is performed. In some cases, to check the size and prevalence of the pathological process, the examination is performed under anesthesia. Classification of cervical cancer reflects the prevalence of the tumor process. Determining the stage of cancer is important for choosing the method of treatment and prognosis. There are four stages (MV), each of which is divided into sub-stages a and b. Stages a and b are divided into 1 and 2. According to the classification of FIGO (International Federation of Obstetricians and Gynecologists), stage 0 corresponds to precancerous changes, and IVb stage is the most severe. The degree of involvement of pelvic and para-aortic (surrounding aorta) lymph nodes increases with the increase in stage.
Preinvasive carcinoma
Invasive cancer, limited to the cervix. Invasive cancer, determined only by microscopy. Cancer sprouts the stroma of the cervix for a thickness of no more than 5 mm and a width of not more than 7 mm. Cancer sprouts the stroma to a depth of more than 3 mm and a width of not more than 7 mm. Depth of germination in stroma from 3 to 5 mm and width not more than 7 mm. Clinically visible cancers within the cervix or a microscopically detectable lesion larger than the stage. Clinically visible lesion is not more than 4 cm. Clinically visible lesion of more than 4 cm. Cancer with spread beyond the cervix to the vagina or surrounding connective tissue. Cancer with spread beyond the cervix to the upper two thirds of the vagina. Cancer with spread beyond the cervix to the surrounding connective tissue. Cancer with spread to the side walls of the pelvis or to the lower third of the vagina. The tumor affects the lower third of the vagina, but does not extend to the side walls of the pelvis. Cancer with spread to the side walls of the pelvis or ureters. Cancer with spread beyond the pelvis or involvement of the bladder and / or rectum. Cancer with spread to neighboring organs
Cervical
Preinvasive cervical carcinoma corresponds to a severe stage of cervical intraepithelial neoplasia (CIN). CIN is classified according to the depth of spread of the tumor process in the epithelium, and also by the degree of differentiation of the tumor cells:
• CIN I - changes take no more than 1/3 of the thickness of the epithelial layer;
• CIN II - changes take 1/2 the thickness of the epithelial layer;
• CIN III - affects the entire thickness of the epithelium.
When abnormal cells germinate the basal membrane of the epithelium, talk about the transition of the precancer to invasive cancer. In 20% of all patients with CIN III, in the absence of treatment over the next 10 years, cervical cancer develops.