Human Papilloma Virus Vaccine and Cervical Cancer
In Hong Kong, cervical cancer ranks tenth among the female cancers (Department of Health, 2013). Although there is a decreasing trend in both the incidence rate and mortality rate of cervical cancer, recent statistics released by the Department of Health (2013) reveal that there are still around 400 new cases of cervical cancer every year and accounts for 3.2 percent of the new cancer cases in 2010. Therefore, it is important for the public to understand more about the causes and possible preventions of cervical cancer.
It has been proven that certain types of human papilloma virus (HPV) contribute to the majority of cervical cancer cases. According to the Department of Health (2007), prevalence of human papilloma virus infection in Hong Kong is approximately 7 to 11 percent in women population. Other than the high-risk HPV 16 and HPV 18, HPV 52 and HPV 58 are also commonly found in Hong Kong, where they account for 12.5 percent and 8.3 percent of cervical cancer cases respectively (Department of Health, 2007). While cervical screening is advocated by the government as an important early detection of cervical cancer, we believe that the significance of human papilloma virus vaccine in preventing cervical cancer should not be neglected as well.
Cervical cancer is cancer that forms in tissues of the cervix. Cervix is the organ connecting the top of virginal tract and lies at the lower part of uterus. Infection of certain types of human papilloma virus (HPV) can cause cervical cancer.
The cervical cancer is commonly diagnosed by progressive clinical procedures. Pelvic examination, physical examination and case history are used to identify any signs and symptoms of cervical cancer. In pap smear, the screening test for cervical cancer, nearly 100 percent of women who have positive result would find abnormal cellular changes in their cervix. There are 4 possible result in a pap smear, namely healthy, atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL) and high-grade squamous intraepithelial lesion (HSIL). According to National Cancer Institute (2012), there are no signs of human papilloma virus infection or abnormal cells shown if the pap test result shows healthy while the result of ASCUS implies that pap smear does not show completely normal but the diagnostic criteria for lesions is absented and pap smear may be repeated to test the specimen. LSIL indicates unusual cellular change of cervix in the size and shape, women with LSIL are recommended to undergo endocervical curettage and colposcopy. For HSIL, there is severe dysplasia and surgical treatments are suggested to remove the precancerous lesions in the cervix. Molecular diagnostic HPV test, which is DNA based or mRNA based, can be intervened to further examine the genome of cancerous cervical cells and viral oncogenic activities as well (Lie and...