What is Cervical Cancer?
Cervical cancer is a cancer that forms in the cervix (the organ connecting the uterus and vagina). There are different types of cervical cancer, but the most common type, known as squamous cell carcinoma (SCC), constitutes about 80 – 85% of all cervical cancers. It is usually caused by an infection by the Human Papilloma Virus (HPV). Other types of cervical cancer, such as adenocarcinoma, small cell carcinoma, adenosquamous, adenosarcoma, melanoma and lymphoma, are not usually related to HPV, and also much rarer. These types of cervical cancer are not as preventable as SCC.
What Causes This Cancer and Who are at Risk?
Infection with the human papilloma virus (HPV) is the most common cause of cervical cancer. This virus can be transmitted through sexual intercourse so women who are sexually active have a higher risk of developing cervical cancer. Women have many sexual partners, or whose sexual partners have had many other partners, have a greater risk. Women who start unprotected sexual intercourse before the age of 16 are at the highest 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. Since the vaccine only covers certain high-risk types of HPV, women should undergo regular Pap smear tests even after vaccination.
Early cervical cancer may present no symptoms. You should see a doctor immediately if you experience the following symptoms:
- 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 emptied bowels
- Leaking of urine or faeces from the vagina
Carcinoma in SITU (CIS or CIN)
Carcinoma in situ (CIN) is a cluster of malignant pre-cancerous cells that is still ‘in situ’ or ‘on site’ and has not moved from its original position and spread to other parts of the body yet.
The Pap smear test can identify CIN of the cervix, where treatment can prevent the development of cancer. It is recommended that women get a Pap smear test once a year after becoming sexually active. This practice should continue until they are 70 years old. If two to three Pap smear tests showed normal results, the woman can consider reducing 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, and leading to dysplasia (abnormal development of cells). In time, 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 through colposcopy, a magnified visual inspection of the cervix aided by using 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.
What Treatments are offered?
The Federation of Gynaecology and Obstetrics (FIGO) classifies cervical cancer into CIN I to III. CIN III is the immediate pre-cursor to cervical cancer. Beyond CIN III, it means the cells have turned into cancer, and will be graded from stage 0 (where cancer is confined only to the skin area) to 4B (where there is advanced, distant spread).
Early stage 1 patients who want to preserve their fertility may opt for conservative surgery to preserve their fertility. Otherwise, it is advisable for the patient to undergo surgery to remove the entire uterus and cervix 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 pathologic evaluation.
Recurrence in the residual cervix is very rare if the cancer has been removed with a trachelectomy. However, patients should continue to be vigilant 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 relapse. Larger early stage tumours may be treated with radiation therapy and chemotherapy. Hysterectomy may follow to provide better local cancer control.
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 significantly as the cancer is discovered late and treatment comes late. Therefore early screening and detection of cervical cancer is critical.