CERVICAL CANCER SCREENING AND PREVENTION
The second most common cancer in women worldwide is cancer of the cervix. However, breakthroughs in newer testing tools and development of an HPV vaccine, has paved the way for better screening and prevention of the dreaded disease.
The cervix, approximately 1 centimetre long, is the lower portion of the uterus. It is located at the end part of the vaginal canal. Its function is to allow menstrual blood to flow periodically from the uterus to the vagina. Aside from this, it also directs the ‘swimming’ sperm from the vagina to the uterus and, eventually, the ovary during intercourse. When the sperm meets the egg in the ovary, it is then fertilized to become the foetus. In time, the foetus is nourished in the uterus until the time when labour occurs and the foetus is allowed to pass through the dilated cervix to the vaginal canal.
The cervix is made up of two different cells, the squamous cells which also line the vaginal wall, and the columnar cells which are also seen in the lining of the uterus. Both of them make up the squamocolumnar junction of the cervix, which is an area of active proliferation of squamous cells. It is this junction where cellular abnormality, takes place as a result of factors associated with coitus. Though cellular changes occur in this area frequently, several factors like HPV infection can transform these changes into dysplastic or cancer cells.
One of the most studied factors causing cancer of the cervix is HPV infection. HPV stands for Human Papilloma Virus. Several types of this virus cause the common warts. However, types 6, 11, 16 and 18 are most commonly implicated in the causation of genital warts. The first two types are known low-risk HPV types, while the latter two are considered high-risk HPV types. They are considered high-risk types as they are the types of HPV that transforms the frequent cellular changes in the squamocolumnar junction into dysplastic or cancer cells over a period of time.
In the past decade, a vaccine against these types of HPV has been developed. Vaccination programs have been rolled out in many countries including Australia and the USA. Besides women, men can also avail of this vaccine to prevent HPV-related penile, anal and oral cancers.
Screening for Cervical Cancer
As for most diseases, early detection is the key for better outcome. One of the best ways to detect early disease is through routine screening.
Recommendations for screening of cervical cancer are varied from country to country due to socioeconomic and other factors involving preventive health policies. However, the general recommendation is to have regular routine Pap smears especially for women age 18-70 years. Guidelines on how regular Pap smears need to be done is based on national guidelines. It is, thus, helpful and necessary to talk to your medical practitioner about having Pap smears as they can fully explain its importance and relevance to you.
Pap smear is done to obtain cells from the vaginal wall and the cervix using a quick and simple procedure done by a medical practitioner. Smears obtained are then sent to the laboratory for cytologic or microscopic studies.
When smears are reported to be abnormal further tests will be discussed by your medical practitioner. Such tests include HPV DNA test and colposcopy. A biopsy can also be performed.
Prevention for Cervical Cancer
As noted above, vaccination is a helpful preventive approach to lowering the risk of cancer of the cervix. However, present available vaccines target only HPV types 16 and 18, there are still other HPV genotypes that can increase the risk of having cervical cancer. Other risk factors such as genetic, dietary and social factors also increase the likelihood of having the disease.
Other notable approaches include limiting the number of sexual partners as HPV infection is sexually transmitted, and cessation of smoking or avoidance of exposure to secondary-smoke. Further, studies have also shown a protective effect of increased dietary beta-carotene against cervical cancers. Therefore, a regular intake of green leafy vegetables and fresh fruits is highly recommended.