How does cervical cancer develop? What misunderstandings should we be aware of regarding cervical cancer?

Women bear great responsibilities for the family and society. The reproductive system of women is the cradle of life and reproduction of offspring. As women live, the reproductive system also undergoes changes from infancy, adolescence, sexual maturity (childbearing age) to aging (perimenopause, menopause), and various diseases may also occur. Common malignant tumors in the female reproductive system are mainly cervical cancer, endometrial cancer and ovarian cancer. Cervical cancer (i.e. cervical cancer) can occur in the neck, lips and endocervical canal of the cervix. However, cervical cancer usually occurs at the junction of the two epithelia of the external cervical os, with more posterior lips, followed by endocervical canal, and then anterior lips. At first, cervical cancer is limited to the epithelial layer of the cervical mucosa and does not penetrate, which is called carcinoma in situ. When cancer invades the submucosal stroma, it is called invasive cancer.

Gynecological cancers are becoming younger

Gynecological tumors can occur at any age, but are most common between the ages of 20 and 50, and are becoming younger. Cervical cancer is the second most common malignant tumor in the world, second only to breast cancer, and ranks first among Chinese women.

About 290,000 women die of cervical cancer each year in the world, of which about 50,000 die of cervical cancer in China, and the rate in rural areas is higher than in cities. According to experts, the subjects of the census and high-risk groups can be determined. Any woman who maintains sexual life should undergo a cervical cytology test once a year, and three consecutive normal tests can reduce the risk of cervical cancer.

The following are high-risk groups: those aged >40 years; those who had their first sexual intercourse at the age of <18 years; those with moderate or severe cervical erosion; those who have promiscuous sexual behavior or poor sexual hygiene; those who have other sexual partners with cervical cancer; those who have persistently positive HPV and DNA tests; those infected with genital warts or herpes simplex virus. Early cervical cancer in women is asymptomatic, and is generally manifested by vaginal bleeding and increased vaginal discharge. Vaginal bleeding can be manifested as contact bleeding, postmenopausal bleeding, or irregular vaginal bleeding.

How cervical cancer progresses

The clinical manifestations of cervical cancer in women are related to the early or late stage of the disease. Early invasive cancer is generally asymptomatic and is often discovered during census screening. As the disease progresses, the main manifestations are vaginal bleeding and vaginal discharge.

1. Vaginal bleeding. Bleeding begins when cancer invades the interstitial blood vessels. The earliest manifestation is a small amount of bleeding after sexual intercourse or a double diagnosis examination, which is called contact bleeding. Contact bleeding can be caused by many reasons. For example, just after the menstruation, because the endometrium has just been repaired, sexual intercourse stimulation can cause bleeding, which is normal; sexual intercourse can also cause bleeding by damaging the vaginal mucosa or the skin of the vaginal opening; cervical diseases, such as cervical polyps and cervicitis, can also cause contact bleeding. In the early stages of cervical cancer and precancerous lesions, new blood vessels are immature, or tumor cells invade the blood vessels in the interstitium, which mainly manifests as vascular damage and bleeding during mechanical stimulation. There may be a small amount of irregular bleeding during menstruation or after menopause. When the lesions are large in the late stage, they manifest as excessive bleeding, and even fatal bleeding due to erosion of large blood vessels.

2. Vaginal discharge. The initial amount is not much, white or light yellow, and has no odor. As the cancerous tissue ruptures and secondary infection occurs, the vagina can discharge a large amount of rice soup, pus, or pus and blood, accompanied by a foul odor. Patients with cervical mucinous adenocarcinoma often complain of watery or mucous vaginal discharge due to the large amount of mucus secreted by the cancerous lesions.

3. Late-stage symptoms. If cancer invades the pelvic connective tissue, compresses the bladder, rectum and sciatic nerve, and affects lymphatic and venous return, frequent urination, urgency, anal swelling, lower limb pain, etc. may occur. If cancer compresses or invades the ureter, hydronephrosis and uremic dysentery may occur, which often appear in the terminal stage due to long-term consumption.

To prevent cervical cancer, we must get rid of four misunderstandings

In recent years, the increase in the incidence and age of cervical cancer has attracted people's attention to this disease. However, there are still many women who have misunderstandings about cervical cancer.

Cervical cancer is not something to be afraid of. It is a disease that can be prevented and treated.

Myth 1: HPV infection = cervical cancer

The occurrence of cervical cancer is closely related to a virus called human papillomavirus (HPV). Studies have shown that persistent infection with high-risk human papillomavirus is a necessary factor for cervical cancer and its precancerous lesions. This virus can be detected in the vast majority of cervical cancer patients.

Any sexually active woman may be infected with HPV through sexual contact. About 80% of women will be infected with the virus in their lifetime.

However, cervical cancer does not necessarily occur after being infected with HPV, because everyone has a certain immunity. Studies have shown that after being infected with HPV, the immune system of most women can enter the body and eliminate HPV. Only a few women cannot eliminate what enters the body. HPV, causing persistent infection with HPV, may lead to cervical precancerous lesions. Some patients will further develop cervical cancer in about 5 to 10 years.

Whether HPV infection will progress to cervical cancer is also related to the type of HPV. There are more than 100 subtypes of HPV virus, and the most common types of HPV infection in the female reproductive tract are 6, 11, 16, and 18. Cervical cancer studies from all over the world have found that HPV6, HPV11, HPV16, and HPV18 are high-risk types, and HPV16 and HPV18 have the highest infection rates in cervical cancer patients.

Myth 2: Cervical erosion can turn into cancer

Many women have the misunderstanding that cervical erosion can cause cervical cancer, so they are very afraid of cervical erosion. There is no necessary connection between the two.

In medicine, when the columnar epithelium in the female cervical canal everts and replaces the cervical squamous epithelium, the doctor will find that the cervix is ​​locally congested and red during examination, which is called "cervical erosion". Erosion is not "rotten" in the true sense, it can be a physiological phenomenon. Under the action of estrogen, the columnar epithelium in the cervical canal of women of childbearing age everts and replaces the cervical squamous epithelium, presenting a "eroded" state. Due to the relatively low estrogen level in the body, "erosion" is rare in women during puberty and before menopause.

It is worth noting that cervical erosion may also be a common inflammatory condition. The appearance of early cervical cancer is very similar to cervical erosion and can be easily confused. Therefore, if cervical erosion is found during a gynecological examination, it should not be taken lightly. Further cytological examination and biopsy are needed to confirm the diagnosis, exclude the possibility of cervical cancer, and treat it correctly.

Myth 3: Not paying attention to gynecological examinations

There is a gradual natural course from HPV infection to the occurrence and development of cervical cancer, which usually lasts about 5 to 10 years. Therefore, as long as women undergo regular cervical cancer screening, it is entirely possible to detect the "signs" of the disease in time and nip it in the bud. At present, the five-year survival rate of patients with early cervical cancer can reach 85% to 90%.