Cervical Cancer
Cervical cancer affects approximately 10,000 women in the United States each year. Cervical cancer is the second most common type of cancer for women worldwide, but because it develops over time, it is also one of the most preventable types of cancer. Deaths from cervical cancer in the United States continue to decline by approximately 2 percent a year. This decline is primarily due to the widespread use of the Pap test to detect cervical abnormalities and allow for early treatment. Most women who have abnormal cervical cell changes that progress to cervical cancer have never had a Pap test or have not had one in the previous three to five years.
Cancer of the cervix tends to occur during midlife. Half of the women diagnosed with the disease are between 35 and 55 years of age. It rarely affects women under age 20, and approximately 20 percent of diagnoses are made in women older than 65. For this reason, it is important for women to continue cervical cancer screening until at least the age of 70.
Types of Cervical Cancer
The cervix is the narrow opening into the uterus from the vagina. The normal “ectocervix” (the portion of the uterus extending into the vagina) is a healthy pink color and is covered with flat, thin cells called squamous cells. The “endocervix” or cervical canal is made up of another kind of cell called columnar cells. The area where these cells meet is called the “transformation zone” (T-zone) and is the most likely location for abnormal or precancerous cells to develop.
Most cervical cancers (80 to 90 percent) are squamous cell cancers. Adenocarcinoma is the second most common type of cervical cancer, accounting for the remaining 10 to 20 percent of cases. Adenocarcinoma develops from the glands that produce mucus in the endocervix. While less common than squamous cell carcinoma, the incidence of adenocarcinoma is on the rise, particularly in younger women.
Causes of Cervical Cancer
Human Papillomavirus (HPV) is found in about 99% of cervical cancers. There are over 100 different types of HPV, the majority of which are considered Low Risk and do not cause cervical cancer. High Risk HPV types may cause cervical cell abnormalities or cancer. More than 70 percent of cervical cancer cases can be attributed to two types of the virus, HPV-16 and HPV-18, often referred to as High Risk HPV Types.
HPV is estimated to be the most common sexually transmitted infection in the United States. In fact, by age 50 approximately 80% of women have been infected with some type of HPV. The majority of women infected with the HPV virus do NOT develop cervical cancer. For most women the HPV infection is transient and 90% of infections resolve spontaneously within 2 years. A small proportion of women do not clear the HPV virus and are considered to have persistent infection. A woman with a persistent HPV infection is at greater risk of developing cervical cell abnormalities and cancer than a woman whose infection resolves on its own.
Signs and Symptoms of Cervical Cancer
Precancerous cervical cell changes and early cancers of the cervix generally do not cause symptoms. Abnormal or irregular vaginal bleeding, pain during sex, or vaginal discharge may be symptoms of more advanced disease.
Notify your healthcare provider if you experience:
- Abnormal bleeding, such as,
- Bleeding between regular menstrual periods
- Bleeding after sexual intercourse
- Bleeding after douching
- Bleeding after a pelvic exam
- Pelvic pain not related to your menstrual cycle
- Heavy or unusual discharge that may be watery, thick, and possibly have a foul odor
- Increased urinary frequency
- Pain during urination
Detecting Cervical Cancer
The best way to determine if precancerous or cancerous cells are present is with a Pap test. The Pap test can determine if cell changes have taken place that may indicate precancerous or cancerous development. (See Pap Testing for more information). In addition to a Pap test, your doctor may recommend an HPV test. The HPV test does not indicate the presence of precancerous or cancerous cells. It determines whether or not a woman has an HPV infection with any of the 13 high-risk HPV types. The test cannot tell you whether your infection is new or if it is persistent. This information will assist you and your doctor to determine appropriate follow-up and intervals for cervical cancer screening. (See HPV Testing for more information).
Protecting Myself from Cervical Cancer
Cervical cancer is one of the most preventable cancers today. If caught early, the 5-year survival rate is almost 100%. Regular Pap testing is the best method to protect against invasive cervical cancer. It is most important to remember that cervical cancer takes many years to develop. Regular Pap tests will help detect any precancerous or abnormal cells early enough so that cervical cancer can be prevented.
In addition to routine Pap testing, you may want to consider minimizing risk factors that could contribute to cervical cancer. Those factors include:
- Multiple sexual partners
- Multiple full-term pregnancies
- Sexual intercourse at an early age
- Chlamydia infection
- Cigarette smoking
- Use of oral contraceptives
- Weakened immune system or HIV infection
