Cervical cancer: Difference between revisions

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{{Short description|Malignancy of the cervix}}
'''Cervical cancer''' is a [[malignancy]] of the [[cervix]].  Worldwide, it is the second most common [[cancer]] of women. It may present with [[vaginal bleeding]] but symptoms may be absent until the cancer is in advanced stages, which has made cervical cancer the focus of intense screening efforts utilizing the [[Pap smear]]. Most scientific studies have found that [[human papillomavirus]] (HPV) infection is responsible for >90% of the cases of cervical cancer. There are 7 most common types of HPV - 16, 18, 31, 33, 42, 52 and 58.[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12571259] Types 16 and 18 being the most common cause of the cancer. Treatment is with [[surgery]] (including [[local exicision]]) in early stages and [[chemotherapy]] and [[radiotherapy]] in advanced stages of the disease. [[HPV vaccine|An effective vaccine]] for the two most common strains of HPV has recently been licenced (see [[#Vaccine|''Vaccine'' section]], below).
{{Infobox medical condition (new)
| name = Cervical cancer
| image =
| caption =
| pronounce =
| field = [[Oncology]], [[Gynecology]]
| symptoms = [[Vaginal bleeding]], [[pelvic pain]], [[dyspareunia]]
| complications = [[Metastasis]], [[kidney failure]], [[pelvic pain]], [[fistula formation]]
| onset =
| duration =
| causes = [[Human papillomavirus]] (HPV) infection
| risks = [[Multiple sexual partners]], [[smoking]], [[immunosuppression]], [[oral contraceptive]] use, [[multiparity]]
| diagnosis = [[Pap smear]], [[Colposcopy]], [[Biopsy]], [[HPV DNA test]]
| differential = [[Endometrial cancer]], [[Vaginal cancer]], [[Cervicitis]]
| prevention = [[HPV vaccine]], [[Regular screening]], [[Safe sex practices]]
| treatment = [[Surgery]], [[Radiotherapy]], [[Chemotherapy]], [[Targeted therapy]]
| prognosis = Good if detected early; poor in advanced stages
| frequency = Second most common [[cancer]] in women worldwide
| deaths = High mortality in low-resource countries
}}


==Signs and symptoms== <!--T:3-->
'''Cervical cancer''' is a [[malignancy]] of the [[cervix]], the lower part of the [[uterus]] that connects to the [[vagina]]. It is the second most common cancer in women worldwide. Early detection through [[screening (medicine)|screening]] has significantly reduced the incidence and mortality rates in developed countries. The most common cause of cervical cancer is persistent infection with high-risk types of the [[human papillomavirus]] (HPV), particularly types 16 and 18.
The early stages of cervical cancer may be completely [[asymptomatic]] (Canavan & Doshi, 2000). [[Vaginal bleeding]], contact bleeding or (rarely) a vaginal mass may indicate the presence of malignancy. In advanced disease, [[metastasis|metastases]] may be present in the [[abdomen]], [[lung]]s or elsewhere.


<!--T:4-->
== Signs and Symptoms ==
The possibility to identify premalignant changes on a cervical smear has made [[Screening (medicine)|screening]] the major cause for referral of women with possible cervical neoplasia. In many countries, women are advised to have a regular [[Pap smear]] to check for premalignant changes.[http://www.aafp.org/afp/20000301/1369.html]  Recommendations for how often a Pap smear should be done vary from once a year to once every five years.  If cervical cancer is detected early, it can be treated without impairing fertility. Consistently abnormal smears may be a reason for further diagnosis despite complete absence of symptoms.


==Diagnosis== <!--T:5-->
In early stages, cervical cancer may be asymptomatic. However, as the disease progresses, symptoms may include:
Diagnosis is made by doing a [[biopsy]] of the cervix, which often involves [[colposcopy]], or a magnified visual inspection of the cervix aided by using an [[acetic acid]] (e.g. vinegar) solution to highlight abnormal cells on the surface of the cervix (the portio).  A [[Pap smear]] is insufficient for the diagnosis.  Many researchers recommend that since more than 99% of invasive cervical cancers worldwide contain [[human papillomavirus]], HPV testing should be carried out together with routine cervical screening (Walboomers ''et al'', 1999). However, given the prevalence of HPV (around 80% infection history among the sexually active population) others suggest that routine HPV testing would cause undue alarm to carriers.


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* [[Vaginal bleeding]] – postcoital bleeding, intermenstrual bleeding, or postmenopausal bleeding.
Further diagnostic procedures are [[loop electrical excision procedure]] (LEEP) and [[conisation]], in which the inner lining of the cervix is removed to be examined pathologically. These are carried out if the biopsy confirms severe dysplasia.
* [[Pelvic pain]] – persistent pain in the lower abdomen or pelvis.
* [[Dyspareunia]] – pain during sexual intercourse.
* Foul-smelling vaginal discharge – often associated with advanced disease.
* Urinary or bowel symptoms – due to tumor invasion of nearby structures.


==Histology== <!--T:7-->
If metastasis occurs, symptoms may involve lungs, liver, bones, or other distant organs.
Types of malignant cervical tumors include the following: [http://www.emedicine.com/med/topic324.htm#section~workup] [http://www.oncolink.upenn.edu/types/article.cfm?c=6&s=17&ss=129&id=8226]


<!--T:8-->
== Causes and Risk Factors ==
* {{ICDO|8070|3}}: [[squamous cell carcinoma]] (about 80-85%)
* {{ICDO|8140|3}}: [[adenocarcinoma]]
* {{ICDO|8560|3}}: [[adenosquamous carcinomas]]
* {{ICDO|8041|3}}: [[small cell carcinoma]]
* {{ICDO|8246|3}}: [[neuroendocrine carcinoma]]
* {{ICDO|8720|3}}: [[melanoma]]
* (varied): [[lymphoma]]


==Staging== <!--T:9-->
The primary cause of cervical cancer is persistent infection with high-risk HPV strains, particularly HPV-16 and HPV-18. Other risk factors include:
Cervical cancer is staged by the [[International Federation of Gynecology and Obstetrics|FIGO]] staging system, which is based on clinical examination, rather than surgical findings.  It allows only the following diagnostic tests to be used in determining the stage: palpation, inspection, colposcopy, endocervical curettage, hysteroscopy, cystoscopy, proctoscopy, intravenous [[urography]], and [[X-ray]] examination of the lungs and skeleton, and cervical conization.  


<!--T:10-->
* Early onset of sexual activity – increased risk of HPV exposure.
The [[TNM]] staging system for cervical cancer is analogous to the FIGO stage.
* Multiple sexual partners – higher likelihood of contracting HPV.
* Stage 0 - full-thickness involvement of the epithelium without invasion into the stroma ([[carcinoma in situ]])
* Smoking – carcinogens in tobacco weaken the immune system.
* Stage I - limited to the uterus
* Long-term use of [[oral contraceptives]] – hormonal changes may play a role.
**IA - diagnosed only by microscopy; no visible lesions
* Immunosuppression – conditions like [[HIV/AIDS]] increase susceptibility.
***IA1 - stromal invasion less than 3 mm in depth and 7 mm or less in horizontal spread
* Multiparity – having multiple full-term pregnancies.
***IA2 - stromal invasion between 3 and 5 mm with horizontal spread of 7 mm or less
* Lack of regular screening – delays early detection and treatment.
**IB - visible lesion or a microscopic lesion with more than 5 mm of depth or horizontal spread of more than 7 mm
***IB1 - visible lesion 4 cm or less in greatest dimension
***IB2 - visible lesion more than 4 cm
* Stage II - invades beyond uterus
**IIA - without parametrial invasion
**IIB - with parametrial invasion
* Stage III - extends to pelvic wall or lower 1/3 of the vagina
**IIIA - involves lower 1/3 of vagina
**IIIB - extends to pelvic wall and/or causes [[hydronephrosis]] or non-functioning kidney
*IVA - invades mucosa of bladder or rectum and/or extends beyond true pelvis
*IVB - distant [[metastasis]]


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== Diagnosis ==
Note that the FIGO stage does not incorporate lymph node involvement in contrast to the [[TNM]] staging for most other cancers.


<!--T:12-->
Cervical cancer is diagnosed using various screening and diagnostic tests, including:
For cases treated surgically, information obtained from the pathologist can be used in assigning a separate pathologic stage but is not to replace the original clinical stage.


<!--T:13-->
* [[Pap smear]] – detects precancerous changes.
For premalignant dysplastic changes, the CIN (cervical intraepithelial neoplasia) grading is used.
* [[HPV DNA test]] – identifies high-risk HPV strains.
* [[Colposcopy]] – magnified inspection of the cervix.
* [[Biopsy]] – confirms cancer through histological examination.
* [[MRI]], [[CT scan]], or [[PET scan]] – assesses tumor spread in advanced cases.


==Pathophysiology== <!--T:14-->
== Histology ==
The [[American Cancer Society]] provides the following list of risk factors for cervical cancer: [[human papillomavirus]] infection, [[tobacco smoking|smoking]], [[HIV]] infection, [[chlamydia]] infection, dietary factors, [[oral contraceptive]]s, multiple [[pregnancy|pregnancies]], low socioeconomic status, use of the hormonal drug [[diethylstilbestrol]] (DES) and a [[family history (medicine)|family history]] of cervical cancer.


<!--T:15-->
The most common histological subtypes of cervical cancer include:
The presence of strains 16, 18 and 31 of [[human papillomavirus]] (HPV) is the prime [[risk factor]] for cervical cancer, and Walboomers ''et al.'' (1999) reported that the presence of HPV is a necessary condition for the development of 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 [[cervical intraepithelial neoplasia]] and cancer.


<!--T:16-->
* [[Squamous cell carcinoma]] – (~80-85%) arises from the ectocervix.
HPV subtypes 16 and 18 introduce two genes called E6 and E7 which code for proteins that inhibit [[p53]] and [[Retinoblastoma_protein|Rb]], which are two important tumor suppressor genes in humans. The p53 gene product is involved in regulation of [[apoptosis]] (cell suicide), and Rb is responsible for halting the [[cell cycle]] at the G1-phase. When Rb function is impaired, the cell is allowed to progress to S-phase and complete mitosis, resulting in proliferation and hence neoplastic transformation.
* [[Adenocarcinoma]] – (~15%) originates from glandular cells of the endocervix.
* [[Adenosquamous carcinoma]] – mixed glandular and squamous features.
* [[Small cell carcinoma]] – aggressive neuroendocrine subtype.
* [[Lymphoma]] and [[melanoma]] – rare occurrences.


<!--T:17-->
== Staging ==
[[Genital warts]] are caused by different HPV types, and are not related to cervical cancer.


<!--T:18-->
Cervical cancer is staged using the FIGO (International Federation of Gynecology and Obstetrics) staging system, which includes:
The medically accepted paradigm, officially endorsed by the [[American Cancer Society]] and other organizations, is that a patient must have been infected with HPV to develop cervical cancer, and is hence viewed as a [[sexually transmitted disease]]. Not all women infected with HPV also develop cervical cancer (Snijders ''et al'', 2006). Use of [[condom]]s will not always prevent transmission.  Likewise, HPV can be transmitted by skin-to-skin-contact with infected areas. HPV is thought to grow preferentially in the [[epithelium]] of the [[glans penis]], and scrupulous [[washing]] and [[cleaning]] of this area may be preventative. The position on [[circumcision]] is controversial: some researchers argue that routine neonatal circumcision is an acceptable way of preventing various diseases (which include cervical carcinoma); others maintain that the benefits do not outweigh the risks.


==Treatment== <!--T:19-->
* Stage 0 – [[Carcinoma in situ]], pre-invasive cancer.
Microinvasive cancer (stage IA) is usually treated by [[hysterectomy]] (removal of the whole uterus including part of the vagina).  For stage IA2, the lymph nodes are removed as well. An alternative for patients who desire to maintain fertility is a local surgical procedure such as a [[Loop electrical excision procedure|LEEP]] or [[cone biopsy]][http://www.webmd.com/hw/womens_conditions/hw27835.asp].
* Stage I – Cancer limited to the cervix.
* IA – Diagnosed only by microscopy.
* IB – Visible lesion or deeper invasion.
* Stage II – Cancer extends beyond the cervix but not to the pelvic wall.
* Stage III – Tumor spreads to the lower vagina, pelvic wall, or causes hydronephrosis.
* Stage IV – Cancer invades adjacent organs (e.g., bladder, rectum) or distant sites.


<!--T:20-->
== Pathophysiology ==
If a cone biopsy was not able to produce [[clear margins]][http://www.meb.uni-bonn.de/cgi-bin/mycite?ExtRef=MEDL/94063663], there is one possible option left for those with early stage cervical cancer who would like to preserve their fertility while treating their cervical cancer: a [[trachelectomy]][http://www.baymoon.com/~gyncancer/library/glossary/bldeftrachelect.htm]. For those in stage I cervical cancer, which has not spread, this is a viable treatment option.  It allows for the preservation of the ovaries and uterus while surgically removing the cervical cancer.  This treatment option is not yet well known amongst doctors and is not yet considered a standard of care. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16493253&query_hl=2&itool=pubmed_docsum] Furthermore, few doctors are trained in this fertility sparing surgical option.  Even the most experienced surgeon won't be able to promise that this can be performed beforehand, as the extent of the spread of cervical cancer is unknown until surgical microscopic examination is completed. As a result, there is always the possibility for the need to convert to a hysterectomy if the surgeon is not able to microscopically confirm clear margins of cervical tissue once the patient is under general anesthesia in the operating room. This can only be done during the same operation if the patient has given consent for a possible hysterectomy prior to the operation. Due to the fact of the possible risk of cancer spread to the lymph nodes in stage 1b cancers and some stage 1a cancers, the surgeon may also need to remove some lymph nodes from around the womb. Once all the checks have been done and if all is well, the cervix will be stitched closed with a [[cerclage]].[http://www.surgeryencyclopedia.com/Ce-Fi/Cervical-Cerclage.html] This will allow for menstruation and fertilization but not dilation for a vaginal delivery, therefore requiring any future births are delivered by cesarean section.  A radical trachelectomy is a smaller operation than hysterectomy, but more importantly allows for the preservation of fertility.  This operation can also be performed vaginally [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15936061&query_hl=5&itool=pubmed_docsuminstead ]instead of abdominally [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15918265&query_hl=8&itool=pubmed_docsum], however there are conflicting opinions as to which approach is better. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8812529&query_hl=13&itool=pubmed_docsum] A radical abdominal trachelectomy with lymphadenecectomy usually only requires a 2 - 3 day hospital stay with most women recovering very quickly (approximately 6 weeks). Complications are generally uncommon, however women who are able to conceive after surgery are prone to preterm labor or possible late miscarriage.[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=10760765&dopt=Abstract]  It is generally recommended to wait at least one year before attempting to become pregnant after surgery.[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=12548192&dopt=Abstract] Recurrence in the residual cervix is a very rare event as long as the cancer has been cleared with the trachelectomy.[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16493253&query_hl=4&itool=pubmed_docsum] Even though recurrence is rare, it is generally recommended for patients to practice vigilant prevention and follow up care including pap screenings/[[colposcopy]], with biopies of the remaining lower uterine segment as needed (every 3-4 months for at least 5 years) to monitor for any recurrance in addition to minimizing any new exposures to HPV through safe sex practices until one is actively trying to conceive. 
Early stages (IB1 and IIA less than 4 cm) can be treated with radical hysterectomy with removal of the lymph nodes or [[radiation therapy]].  Radiation therapy is given as external beam radiotherapy to the pelvis and [[brachytherapy]] (internal radiation).  For patients treated with surgery who have high risk features found on pathologic examination, radiation therapy with or without chemotherapy is given in order to reduce the risk of relapse.


<!--T:21-->
HPV-related cervical cancer involves viral oncogenes, particularly E6 and E7, which:
Larger early stage tumors (IB2 and IIA more than 4 cm) may be treated with radiation therapy and [[cisplatin]]-based chemotherapy, hysterectomy (which then usually requires [[adjuvant]] radiation therapy), or cisplatin chemotherapy followed by hysterectomy. 


<!--T:22-->
* E6 – Inactivates tumor suppressor p53, preventing apoptosis.
Advanced stage tumors (IIB-IVA) are treated with radiation therapy and [[cisplatin]]-based chemotherapy.
* E7 – Inhibits [[retinoblastoma protein]] (Rb), allowing uncontrolled cell division.


<!--T:23-->
These changes lead to cervical intraepithelial neoplasia (CIN) and, over time, invasive cancer.
On [[June 15]], [[2006]] Food and Drug Administration has approved [http://www.fda.gov/bbs/topics/NEWS/2006/NEW01391.html] uses combination of two chemotherapy drugs, [[Hycamtin]] and [[cisplatin]] for women with late-stage (IVB) cervical cancer treatment. Combination treatment has significant risk of [[neutropenia]], [[anemia]], and [[thrombocytopenia]] side effects. Hycamtin is manufactured by GlaxoSmithKline.


==Epidemiology== <!--T:24-->
== Prevention ==
Worldwide, cervical cancer is the second most common cancer in women (after [[breast cancer]]) and is the third leading killer (behind breast and [[lung cancer]]).  It affects about 16 per 100,000 women per year and causes death in about 9 per 100,000 per year.


<!--T:25-->
Effective prevention strategies include:
In the [[United States]], however, cervical cancer is only the 8th most common cancer of women. About 12,800 women in the United States are diagnosed with cervical cancer and about 4,800 die each year (Canavan & Doshi, 2000). Among gynecological cancers it ranks behind [[endometrial cancer]] and [[ovarian cancer]].  The incidence and mortality figure for the U.S. are about half that of the rest of the world, a difference which can be attributed in part to the success of screening with the [[Pap smear]].[http://www.aafp.org/afp/20000301/1369.html]


<!--T:26-->
* [[HPV vaccine]] – protects against HPV-16, 18, 31, 33, 45, 52, 58.
In 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, one in 65 of all British women born since 1950 would have died from cancer of the cervix.
* Regular screening – routine Pap smears and HPV testing.
* Safe sex practices – use of [[condom]]s reduces HPV transmission.
* Smoking cessation – lowers the risk of progression from HPV infection to cancer.


<!--T:27-->
== Treatment ==
A study published in 2002 (Castellsagué ''et al'') reports that male circumcision can reduce the risk of penile human papillomavirus (HPV) infection in the man, and as a result that of cervical cancer in his female partner. The authors do state that "it would not make sense to promote circumcision as a way to control cervical cancer in the United States, where Pap smears usually detect it at a treatable stage". In contrast to this claim, Menczer (2004) quotes research that male circumcision probably does not contribute to a lower incidence of cervical cancer in Jewish populations.


==History== <!--T:28-->
Treatment depends on the stage and spread of the cancer:
[[Epidemiology|Epidemiologists]] working in the early 20th century noted that:
#Cervical cancer was common in female [[sex worker]]s.
#It was rare in [[nun]]s, 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.
#It was rare in Jewish women.[http://www.ima.org.il/imaj/ar03feb-11.pdf]


<!--T:29-->
* Stage 0 (Carcinoma in situ):
This led to the deduction that cervical cancer could be caused by a sexually transmitted agent. Initial research in the 1950s and 1960s put the blame on [[smegma]] (e.g. Heins ''et al'' 1958), but it wasn't until the 1970s that [[human papillomavirus]] (HPV) was identified. It has since been demonstrated that HPV is implicated in all cervical cancers.  Specific viral subtypes implicated are HPV 16, 18 and 31.
* Loop electrical excision procedure (LEEP) or cone biopsy.
* Hysterectomy in some cases.


==Vaccine== <!--T:30-->
* Early-stage (IA & IB):
{{main|HPV vaccine}}
* Radical hysterectomy with pelvic lymph node dissection.
* Radiotherapy for inoperable cases.


<!--T:31-->
* Locally advanced (II & III):
[[Merck & Co.]] has developed a vaccine against four strains of HPV called Gardasil™. It is now on the market after receiving Food and Drug Administration approval [http://www.fda.gov/bbs/topics/NEWS/2006/NEW01385.html] on [[June 8]], [[2006]]. Gardasil™ is targeting girls and women age 9 to 26 because the vaccine works best when given to girls before they begin having sex.
* Concurrent radiotherapy and chemotherapy.
* Cisplatin-based chemotherapy.


<!--T:32-->
* Advanced-stage (IV):
A bi-valent vaccine to prevent HPV infection has been also developed by Israel and tested (Harper ''et al'' 2004). It confers immunity against the two (thus, bi-valent) HPV strains 16 & 18. 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).
* Palliative chemotherapy.
* Targeted therapy with bevacizumab (anti-angiogenesis drug).


<!--T:33-->
== Epidemiology ==
[[Advaxis, Inc]] (OTCBB: ADXS) is developing a [[therapeutic vaccine]] to treat existing cervical cancer. The therapeutic vaccine, Lovaxin C, has entered clinical trials in March 2006. The vaccine is based on a modified, genetically engineered strain of the bacteria [[Listeria monocytogenes]].


==External links== <!--T:34-->
* Cervical cancer is the fourth most common cancer in women worldwide.
*[http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_What_are_the_risk_factors_for_cervical_cancer_8.asp?sitearea= What are the risk factors for cervical cancer?] (American Cancer Society).
* High incidence in developing countries due to low screening rates.
* HPV-related cancers contribute to over 99% of cases.


==References== <!--T:35-->
In developed countries, routine HPV vaccination and Pap screening have significantly reduced mortality rates.
* Canavan TP, Doshi NR. ''Cervical cancer''. Am Fam Physician 2000;61:1369-76. [http://www.aafp.org/afp/20000301/1369.html Fulltext]. PMID 10735343.
 
* Castellsagué 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. [http://content.nejm.org/cgi/content/short/346/15/1105 Fulltext]. PMID 11948269.
== History ==
* Heins HC, Dennis EJ, Pratt-Thomas HR. The possible role of smegma in carcinoma of the cervix. ''Am J Obstet Gynec'' 1958:76;726-735. PMID 13583012.
 
* 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.'' [[The Lancet|Lancet]] 2004;364(9447):1757-65. PMID 15541448.
Early studies suggested that cervical cancer was associated with sexual activity:
* Menczer J. ''The low incidence of cervical cancer in Jewish women: has the puzzle finally been solved?'' Isr Med Assoc J 2003;5:120-3. [http://www.ima.org.il/imaj/ar03feb-11.pdf PDF]. PMID 12674663.
 
* Lehtinen M, Dillner J. ''Preventive human papillomavirus vaccination.'' Sex Transm Infect 2002;78:4-6. [http://sti.bmjjournals.com/cgi/content/full/78/1/4 Fulltext]. PMID 11872848.
* More common in sexually active women.
* 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.
* Rare in nuns, except those who had been sexually active before.
* Snijders PJ, Steenbergen RD, Heideman DA, Meijer CJ. ''HPV-mediated cervical carcinogenesis: concepts and clinical implications'' J Pathol. 2006;208:152-64. PMID 16362994.
* More prevalent in women whose male partners had multiple sexual partners.
* 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.
 
* International Angency for Research on Cancer, Lyons, France [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12571259] ''The 7 most common types of HPV virus.''
The link to HPV was confirmed in the 1970s, and HPV testing is now a crucial part of screening programs.
 
== See Also ==
 
* [[HPV vaccine]]
* [[Pap smear]]
* [[Gynecologic oncology]]
* [[Cancer staging]]
* [[Oncology]]
* [[Colposcopy]]
* [[Hysterectomy]]
* [[Loop electrical excision procedure]]
 
== External Links ==
* [https://www.who.int/health-topics/cervical-cancer WHO: Cervical Cancer Information]
* [https://www.cancer.org/cancer/cervical-cancer.html American Cancer Society: Cervical Cancer]
* [https://www.cdc.gov/cancer/cervical/ CDC: Cervical Cancer]


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{{Tumors}}
{{Tumors}}
 
{{Gynecology}}
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{{Oncology}}
{{stub}}
[[Category:Oncology]]
[[Category:Oncology]]
[[Category:Gynecology]]
[[Category:Gynecology]]
[[Category:Types of cancer]]
[[Category:Types of cancer]]
 
[[Category:HPV-associated cancers]]
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[[Category:Women's health]]
{{modified}}

Revision as of 16:24, 20 March 2025

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Malignancy of the cervix


Cervical cancer
[[File:|250px|alt=|]]
Synonyms N/A
Pronounce
Field Oncology, Gynecology
Symptoms Vaginal bleeding, pelvic pain, dyspareunia
Complications Metastasis, kidney failure, pelvic pain, fistula formation
Onset
Duration
Types N/A
Causes Human papillomavirus (HPV) infection
Risks Multiple sexual partners, smoking, immunosuppression, oral contraceptive use, multiparity
Diagnosis Pap smear, Colposcopy, Biopsy, HPV DNA test
Differential diagnosis Endometrial cancer, Vaginal cancer, Cervicitis
Prevention HPV vaccine, Regular screening, Safe sex practices
Treatment Surgery, Radiotherapy, Chemotherapy, Targeted therapy
Medication N/A
Prognosis Good if detected early; poor in advanced stages
Frequency Second most common cancer in women worldwide
Deaths High mortality in low-resource countries


Cervical cancer is a malignancy of the cervix, the lower part of the uterus that connects to the vagina. It is the second most common cancer in women worldwide. Early detection through screening has significantly reduced the incidence and mortality rates in developed countries. The most common cause of cervical cancer is persistent infection with high-risk types of the human papillomavirus (HPV), particularly types 16 and 18.

Signs and Symptoms

In early stages, cervical cancer may be asymptomatic. However, as the disease progresses, symptoms may include:

  • Vaginal bleeding – postcoital bleeding, intermenstrual bleeding, or postmenopausal bleeding.
  • Pelvic pain – persistent pain in the lower abdomen or pelvis.
  • Dyspareunia – pain during sexual intercourse.
  • Foul-smelling vaginal discharge – often associated with advanced disease.
  • Urinary or bowel symptoms – due to tumor invasion of nearby structures.

If metastasis occurs, symptoms may involve lungs, liver, bones, or other distant organs.

Causes and Risk Factors

The primary cause of cervical cancer is persistent infection with high-risk HPV strains, particularly HPV-16 and HPV-18. Other risk factors include:

  • Early onset of sexual activity – increased risk of HPV exposure.
  • Multiple sexual partners – higher likelihood of contracting HPV.
  • Smoking – carcinogens in tobacco weaken the immune system.
  • Long-term use of oral contraceptives – hormonal changes may play a role.
  • Immunosuppression – conditions like HIV/AIDS increase susceptibility.
  • Multiparity – having multiple full-term pregnancies.
  • Lack of regular screening – delays early detection and treatment.

Diagnosis

Cervical cancer is diagnosed using various screening and diagnostic tests, including:

  • Pap smear – detects precancerous changes.
  • HPV DNA test – identifies high-risk HPV strains.
  • Colposcopy – magnified inspection of the cervix.
  • Biopsy – confirms cancer through histological examination.
  • MRI, CT scan, or PET scan – assesses tumor spread in advanced cases.

Histology

The most common histological subtypes of cervical cancer include:

Staging

Cervical cancer is staged using the FIGO (International Federation of Gynecology and Obstetrics) staging system, which includes:

  • Stage 0 – Carcinoma in situ, pre-invasive cancer.
  • Stage I – Cancer limited to the cervix.
  • IA – Diagnosed only by microscopy.
  • IB – Visible lesion or deeper invasion.
  • Stage II – Cancer extends beyond the cervix but not to the pelvic wall.
  • Stage III – Tumor spreads to the lower vagina, pelvic wall, or causes hydronephrosis.
  • Stage IV – Cancer invades adjacent organs (e.g., bladder, rectum) or distant sites.

Pathophysiology

HPV-related cervical cancer involves viral oncogenes, particularly E6 and E7, which:

  • E6 – Inactivates tumor suppressor p53, preventing apoptosis.
  • E7 – Inhibits retinoblastoma protein (Rb), allowing uncontrolled cell division.

These changes lead to cervical intraepithelial neoplasia (CIN) and, over time, invasive cancer.

Prevention

Effective prevention strategies include:

  • HPV vaccine – protects against HPV-16, 18, 31, 33, 45, 52, 58.
  • Regular screening – routine Pap smears and HPV testing.
  • Safe sex practices – use of condoms reduces HPV transmission.
  • Smoking cessation – lowers the risk of progression from HPV infection to cancer.

Treatment

Treatment depends on the stage and spread of the cancer:

  • Stage 0 (Carcinoma in situ):
  • Loop electrical excision procedure (LEEP) or cone biopsy.
  • Hysterectomy in some cases.
  • Early-stage (IA & IB):
  • Radical hysterectomy with pelvic lymph node dissection.
  • Radiotherapy for inoperable cases.
  • Locally advanced (II & III):
  • Concurrent radiotherapy and chemotherapy.
  • Cisplatin-based chemotherapy.
  • Advanced-stage (IV):
  • Palliative chemotherapy.
  • Targeted therapy with bevacizumab (anti-angiogenesis drug).

Epidemiology

  • Cervical cancer is the fourth most common cancer in women worldwide.
  • High incidence in developing countries due to low screening rates.
  • HPV-related cancers contribute to over 99% of cases.

In developed countries, routine HPV vaccination and Pap screening have significantly reduced mortality rates.

History

Early studies suggested that cervical cancer was associated with sexual activity:

  • More common in sexually active women.
  • Rare in nuns, except those who had been sexually active before.
  • More prevalent in women whose male partners had multiple sexual partners.

The link to HPV was confirmed in the 1970s, and HPV testing is now a crucial part of screening programs.

See Also

External Links









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