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Cervical cancer is malignancy of the cervix; it is one of the more common cancers affecting women of reproductive age. It may present with vaginal bleeding but is often only detected in advanced stages, which has made it the focus of intense screening efforts. Early stages are treated with local surgical therapy; advanced stages require hysterectomy (removal of the whole uterus including part of the vagina) and adjuvant therapy such as radiation therapy or chemotherapy.
Diagnosis
Diagnosis is made by biopsy. A Pap smear is insufficient for the diagnosis, although it may indicate the presence of carcinoma in situ or full-blown malignancy. Many researchers recommend that, since in excess of 90% of invasive cervical cancers worldwide contain human papillomavirus, HPV testing should be carried out together with routine cervical screening (Walboomers et al 1999).
Risk factors
The presence of strains 16, 18 and 31 of human papillomavirus (HPV) is the prime risk factors for cervical cancer. A virus cancer link with HPV has been found to trigger alterations in the cells of the cervix, leading to the development of cancer (see the role of apoptosis in cell damage or infection). Walboomers et al. (1999) report that the presence of HPV is a necessary condition for the development of cervical cancer. The strains of HPV linked to cervical cancer (strains 16, 18 and 31), are not the ones that cause genital warts.
Epidemiologists working in the early 20th century noted that:
- Cervical cancer was common in female sex workers.
- It was rare in nuns, except for those who had been sexually active before entering the convent.
- It was more common in the second wives of men whose first wives had died from cervical cancer.
- Its was rare in the wives of Jewish and other circumcised men.
This led to the deduction that cervical cancer could be caused by a sexually transmitted agent. But it wasn't until the 1970s that this agent was identified as the human papillomavirus. It has since been demonstrated that the virus is implicated in 90% of cervical cancers.
Women are advised to have a pap smear annually to check for precancerous cells, or other abnormalities. If cervical cancer is detected early, it can be treated without impairing fertility.
A study published in 2002 (Castellsagué et al) found that male circumcision reduces the risks of penile human papillomavirus (HPV) infection in the man and as a result that of cervical cancer in his female partner.
In predominantly non-circumcising Great Britain the incidence of cervical cancer has reached alarming proportions in that the mortality in England and Wales in women younger than 35 years rose three-fold from 1967 to 1987. In a study published in 2004 (Peto J et al) scientists from the London School of Hygiene and Tropical Medicine found that had it not been for effective cervical screening fully one in 65 of all British women born since 1950 would have died from cancer of the cervix.
In a 1986 study performed in China[1] (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=1654190), the presence of smegma was specifically identified as a high risk factor in causing cervical cancer. This supports the findings of the earlier 1958 study by Heins et al, which concluded:
- "The clinical and sociological facts and observations concerning smegma strongly indicate that in some way it is implicated in the genesis of penile and cervical carcinoma. Whole raw smegma as well as some of its components is stimulatory to the cervico-vaginal epithelium of mice and invasive carcinoma will eventuate if the stimulus persists."
The American cancer Society provides the following list of risk factors for cervical cancer. They are: human papillomavirus infection, smoking, HIV infection, chlamydia infection, dietary factors, oral contraceptives, multiple pregnancies, low socioeconomic status, use of the hormonal drug diethylstilbestrol (DES) and a family history of cervical cancer.
Vaccine
A bi-valent vaccine to prevent HPV infection has been developed and tested (Harper et al 2004). This vaccine, when it is licenced and goes into production, could substantially reduce the incidence of HPV infection, the incidence of cervical cancer, and mortality. (Lehtinen & Dillner 2002).
Notable patients
Notable people who have suffered from or died of cervical cancer:
References
- Castellsague X, Bosch FX, Munoz N, Meijer CJ, Shah KV, de Sanjose S, Eluf-Neto J, Ngelangel CA, Chichareon S, Smith JS, Herrero R, Moreno V, Franceschi S; International Agency for Research on Cancer Multicenter Cervical Cancer Study Group. Male circumcision, penile human Papillomavirus infection, and cervical cancer in female partners. N Engl J Med 2002;346:1105-12. Fulltext (http://content.nejm.org/cgi/content/short/346/15/1105). PMID 11948269.
- Harper DM, Franco EL, Wheeler C, Ferris DG, Jenkins D, Schuind A, Zahaf T, Innis B, Naud P, De Carvalho NS, Roteli-Martins CM, Teixeira J, Blatter MM, Korn AP, Quint W, Dubin G; GlaxoSmithKline HPV Vaccine Study Group. Efficacy of a bivalent L1 virus-like particle vaccine in prevention of infection with human papillomavirus types 16 and 18 in young women: a randomised controlled trial. Lancet 2004;364(9447):1757-65. PMID 15541448.
- Heins HC, Dennis EJ, Pratt-Thomas HR. The possible role of smegma in carcinoma of the cervix. Am J Obstet Gynecol 1958;76:726-33, discussion 733-5. Fulltext (http://www.circs.org/library/heins/index.html).
- Lehtinen M, Dillner J. Preventive human papillomavirus vaccination. Sex Transm Infect 2002;78:4-6. Fulltext (http://sti.bmjjournals.com/cgi/content/full/78/1/4). PMID 11872848.
- Peto J, Gilham C, Fletcher O, Matthews FE. The cervical cancer epidemic that screening has prevented in the UK. Lancet 2004;364:249-56. PMID 15262102.
- Walboomers JM, Jacobs MV, Manos MM, Bosch FX, Kummer JA, Shah KV, Snijders PJ, Peto J, Meijer CJ, Munoz N. Human papillomavirus is a necessary cause of invasive cervical cancer worldwide. J Pathol 1999;189:12-9. PMID 10451482.
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