Understanding Cervical Cancer

Cervical cancer is a cancer which develops in the neck of the womb.  Although it is the tenth most common cancer in Singaporean women, its prevalence has steadily declined over the past 50 years because it is highly preventable and treatable, especially when picked up early.   Medicus patient case manager recently met up with Dr. Lynette Ngo from Curie Oncology to understand more about cervical cancer and how it can be prevented.

What are the signs and symptoms of cervical cancer?

Early cervical cancer is typically asymptomatic (no signs and symptoms) and this leaves many women unaware of its presence until the later stages. Thus, regular cervical cancer screening is essential.

Common symptoms of cervical cancer:

• Irregular or heavy vaginal bleeding, especially between menses or after menopause
• Pain during sexual intercourse or bleeding after intercourse
• Abnormal vaginal discharge
• Pelvic or lower back pain

What are the cervical cancer risk factors?

The most important risk factor for cervical cancer is Human Papillomavirus (HPV).  HPV spreads from person to person during skin-to-skin contact. It is the most common sexually transmitted virus.  It is responsible for 99% of cervical cancers. Having persistent HPV infection poses a major risk for cervical cancer.  Fortunately, HPV vaccinations are now widely available.

Other risk factors:

• Factors predisposing to HPV infections, such as multiple sexual partners
• Cigarette smoking
• Oral contraceptive use for more than 5 years

How can I prevent cervical cancer?

HPV vaccination greatly reduces the likelihood for developing cervical cancer. It is safe and effective, and readily available in Singapore.

Other preventive measures:

• Screening regularly for cervical cancer with PAP test and HPV test
• Practicing safe sex by using condoms
• Limiting the number of sexual partners
• Avoiding sexual intercourse with people who have had many partners
• Avoiding sexual intervourse with people who are infected with genital warts
• Not smoking

More about the cervical cancer vaccine

HPV vaccines have been proven to be effective in preventing cervical cancer and the pre-cancer, Cervical Intraepithelial Neoplasia (CIN).

There are more than 150 types or “strains” of HPV. Most HPV infections do not cause any health problems. Some types of HPV cause warts. These warts can grow anywhere on the body and are often found on the hands and feet. They are contagious and spread by touch, but they do not cause cancer. About 40 types of HPV are called “genital HPV.” Genital HPV spreads by skin contact, usually during vaginal, anal, and oral sex. Some types of genital HPV cause genital warts. They do not lead to cancer. They are known as low-risk HPV. Common types of low-risk HPV include HPV-6 and HPV-11. Other types of genital HPV such as HPV-16 and HPV-18 are known as high-risk HPV. Over time, the infection can turn normal cells into precancer or cancer.

There are 3 HPV vaccines currently available. Gardasil 9 helps prevent infection from 7 high-risk HPV: HPV-16, HPV-18, and 5 other less common types of HPV linked to cancer. The vaccine can also prevent 2 low-risk HPV known to cause 90% of genital warts.

The other 2 vaccines are Gardasil, which helps prevent infection from 2 high-risk HPV and 2 low-risk HPV, while Cervarix helps prevent infection from 2 high-risk HPV.

The vaccine is most effective for women who are not HPV-positive and have never had sex. Those who are already sexually active, have had prior genital warts, abnormal Pap test or HPV infection can still be vaccinated although it is less helpful.  However, the HPV vaccine cannot eliminate any existing HPV infection.

After vaccination, regular screening is still necessary for cervical cancer prevention as there are other cancer-causing subtypes of HPV that are not covered by current vaccines.

Cervical cancer screening to detect cervical cancer early

Although prevention is better than cure, it is still important to screen regularly for cervical cancer.   Diagnosing it at an early stage is associated with a good prognosis, with a 5 year survival between 80% to 95%.

There are 2 screening tests for cervical cancer: Pap testing and HPV testing.  Pap testing is recommended for women who have had sex or are sexually active, once every three years, from the age of 25 years.

HPV-DNA test has been found to be much more sensitive than the PAP test in detecting cervical cancer and pre-cancers. HPV DNA testing is recommended for women once every 5 years from the age of 30 years.

Cervical cancer diagnosis and treatment

Cervical cancer is typically diagnosed with an abnormal PAP test or HPV DNA test.  Confirmatory tests will then need to be performed. This includes:

• Colposcopy:  A special instrument, the colposcope, helps doctors to visually examine the cervix for any abnormalities, lesions or tumours
• Cervical biopsy:  A sample of abnormal tissue is obtained for the cervix, for more definitive examination by microscop

Your cervical cancer specialist will help determine the most suitable treatment for you. The various treatments include:

• Surgery: The removal of malignant tissues and any surrounding damage
• Radiotherapy: High doses of radiation are used to kill cancerous cells and reduce tumour size
• Chemotherapy: Drug treatments to kill rapidly multiplying cancerous cells
• Immunotherapy: A treatment for late-stage cervical cancer which utilizes the body’s own immune cells