Overview
The cervix is the neck of the tissue that is cylinder-shaped and connects the vagina and the uterus. The cervix is located at the lower part of the uterus and is composed mostly of fibromuscular tissue. The cervix has two main portions:
- Ectocervix is the part of the cervix that can be seen from the inside of the vagina during a gynecological examination. An opening in the ectocervix center, known as the outer os, allows the passage between the uterus and the vagina.
- Endocervix or endocervical canal is a tunnel from the outer os to the uterus through the cervix.
What is cervical cancer?
Cervical cancer is a type of cancer that occurs in the cervix cells. Different strains of the human papillomavirus (HPV), a sexually transmitted infection, play a key role in causing cervical cancer. It starts when healthy cells on the cervix surface change and grow out of control, forming a mass called a tumor. Many of the abnormal cells go away unnoticed, while some can become cancerous. This disease phase is called dysplasia which represents an abnormal cell growth. The defective cells also called precancerous tissue should be removed to avoid developing cancer.
Cervical cancer may affect deeper tissues of the cervix and can spread to other parts of body the (metastasize), including the lungs, bladder, liver, vagina, and rectum. The body’s immune system usually stops the virus from causing damage when exposed to HPV. Yet, the virus survives for years in a small percentage of people, contributing to the process which causes some cervical cells to become cancerous.
Causes
What causes cervical cancer?
Most of the cervical cancer cases occurs due to sexually transmitted human papillomavirus (HPV). There are about 100 different HPV strains of which only high-risk HPV types such as HPV-16 and HPV-18 are the two forms which is one of the most common cervical cancer causes. Getting diagnosed with a cancer-causing HPV strain does not mean you are going to get cervical cancer. The majority of HPV infections are eliminated by the immune system.
Most of the women infected with HPV virus do not develop cervical cancer. A woman with a persistent HPV infection is at greater risk of developing abnormalities in the cervical cells leading to cancer. Some types of this virus are capable of transforming normal cervical cells into abnormal ones. Some of these abnormal cells can then develop into cervical cancer in a small number of cases, and usually over a long period of time (from several years to several decades).