Cervical Cancer

What Causes this Cancer and Who is at Risk?

HPV infection is the most common cause of cervical cancer. Since this virus can be transmitted through sexual intercourse, women who are sexually active have a higher risk of getting infected. Women who have many sexual partners, or whose sexual partner have had many other partners, are at greater risk. Women who start having unprotected sexual intercourse from a young age are most at risk.

Vaccines are effective against strains of HPV responsible for up to 85% of all cervical cancers. HPV vaccines are targeted at females from a young age, as the vaccine only works if given before infection occurs. However, the vaccine only covers certain high-risk types of HPV, and women advised to have regular Pap smear tests even after vaccination.

• Vaginal bleeding or the presence of abnormal discharge
• Pain during sexual intercourse
• Lower back or pelvic pain
• Painful or difficult urination and cloudy urine
• Chronic constipation and feeling of presence of stools despite having gone to the toilet
• Leaking of urine or faeces from the vagina

Carcinoma in SITU (CIS or CIN)

Carcinoma in situ (CIN) is a group of harmful pre-cancerous cells that is still ‘in situ’ or ‘on site’ and has not moved from its original position and has not spread to other parts of the body yet. In Singapore and other developed countries, the widespread use of cervical screening programmes has helped to find CIN and reduced the numbers of invasive cervical cancer.

The Pap smear test can identify CIN of the cervix, where treatment can stop the growth of cancer. It is advised that women get the test once a year after becoming sexually active. This practice should continue until they are 70 years old. If 2 – 3 Pap smear tests show normal results, the woman can reduce the frequency to once every 2 – 3 years. However, women who are at high risk should continue to undergo a Pap smear test every year.

Not all women with HPV infections develop CIN, and not all women who have CIN develop cervical cancer. Many HPV infections can be cleared by the immune system, just like any other infection.

However, certain strains of HPV can stay in the cervix for many years, changing the genetic make-up of the cervical cells over time and leading to dysplasia (abnormal development of cells). If left untreated, severe dysplasia can develop into invasive cervical cancer.

CIN usually produces no symptoms at all. This would be the best time to screen for cancer as treatment at this point tends to be the most effective.

While the Pap smear is an effective cervical cancer screening test, a biopsy is needed to confirm the presence of cervical cancer or pre-cancer. This can be done during a colposcopy, a procedure that magnifies visual inspection of the cervix with the use of a dilute acidic solution to highlight abnormal cells on the surface of the cervix. It is a painless, 15-minute outpatient procedure.

Further diagnostic procedures include the loop electrical excision procedure (LEEP), cone biopsies, and punch biopsies.

Early stage 1 patients who want to keep their fertility may opt for conservative surgery. Otherwise, it is advisable for the patient to undergo surgery to remove the cervix and part of the vagina in a procedure known as trachelectomy. It is recommended to wait at least 1 year before attempting to conceive after surgery. Due to the possible risk of cancer spreading to the lymph nodes in late stage 1 cancer, the surgeon may have to remove lymph nodes from around the uterus for further examination.

Any return of the cancer in the remaining cervix is very rare if the cancer has been removed with a trachelectomy. However, patients should continue to be watchful in prevention and follow-up care, including undergoing regular Pap smear tests.

Early stage tumours can be treated with radical hysterectomy (removal of the uterus) with lymph node removal. Radiation therapy with or without chemotherapy may be given after surgery to reduce the risk of the cancer returning. Larger early stage tumours may be treated with radiation therapy and chemotherapy. Hysterectomy may follow to control the local cancer better.

Advanced stage tumours (stages 2B to 4B) are usually treated with chemo-radiation therapy.

What are the Chances of Survival for Cervical Cancer?

If detected early, the chances of surviving cervical cancer is as high as 92%. However, the survival rate dips greatly if the cancer is discovered and treated late. Therefore early screening and detection of cervical cancer is critical.