Cervical Intraepithelial Neoplasia.CIN
Cervical Intraepithelial Neoplasia, CIN
Cervical IntraepithelialNeoplasiaCervical intraepithelial neoplasia(CiN),alsoknown as cervical dysplasia,isthe abnormalgrowth of cells on the surface of the cervixthat could potentially lead to cervicalcancer.[1] More specifically, CiN refers to thepotentially precancerous transformation ofcells of the cervix
Cervical Intraepithelial Neoplasia ❖Cervical intraepithelial neoplasia (CIN), also known as cervical dysplasia, is the abnormal growth of cells on the surface of the cervix that could potentially lead to cervical cancer.[1] More specifically, CIN refers to the potentially precancerous transformation of cells of the cervix
CIN most commonly occurs at thesquamocolumnar junction of the cervix, atransitional area between the squamousepithelium of the vagina and the columnarepithelium of the endocervix.[2]j It can alsooccur in vaginal walls and vulvar epithelium.CIN is graded on a 1-3 scale, with 3 being themost abnormal (see classification section84学时below)
CIN most commonly occurs at the squamocolumnar junction of the cervix, a transitional area between the squamous epithelium of the vagina and the columnar epithelium of the endocervix.[2] It can also occur in vaginal walls and vulvar epithelium. CIN is graded on a 1-3 scale, with 3 being the most abnormal (see classification section below) 84学时
Human papilloma virus (HPV) infection is, necessaryfor the development of CiN, but not all with thisinfection develop cervical cancer. A large number ofwomen with HPV infection never develop CIN orcervical cancer. Typically, HPV resolves on its own.However,those with anHPV infection thatlastsmore than 1 or 2 years have a higher risk ofdeveloping a higher grade of CIN.Like other intraepithelial neoplasias, CIN is notcancer and is usually curable.[3] Most cases of CINeither remainstable or are eliminated by theperson's immune system without need forintervention. However, a small percentage of casesprogress to cervical cancer, typically cervicalsquamous cell carcinoma (SCC), if left untreated
Human papilloma virus (HPV) infection is necessary for the development of CIN, but not all with this infection develop cervical cancer. A large number of women with HPV infection never develop CIN or cervical cancer. Typically, HPV resolves on its own. However, those with an HPV infection that lasts more than 1 or 2 years have a higher risk of developing a higher grade of CIN. Like other intraepithelial neoplasias, CIN is not cancer and is usually curable.[3] Most cases of CIN either remain stable or are eliminated by the person's immune system without need for intervention. However, a small percentage of cases progress to cervical cancer, typically cervical squamous cell carcinoma (SCC), if left untreated
Signs and symptomsThere are no specific symptoms of CIN alone.Generally,signs and symptoms of cervical cancerinclude:[7]abnormal or post-menopausal bleedingabnormal dischargechanges in bladder or bowel functionpelvic pain on examinationabnormal appearance or palpation of cervix.Hpv infection of the vulva and vagina can causegenital warts or be asymptomatic
Signs and symptoms There are no specific symptoms of CIN alone. Generally, signs and symptoms of cervical cancer include:[7] abnormal or post-menopausal bleeding abnormal discharge changes in bladder or bowel function pelvic pain on examination abnormal appearance or palpation of cervix. HPV infection of the vulva and vagina can cause genital warts or be asymptomatic
CausesThe cause of CiN is chronic infection of thecervix with HPV, especially infection with high.risk HPV types i6 or 18. It is thought that thehigh-risk HPV infections have the ability toinactivate tumor suppressor genes such as thep53 gene and the RB'gene, thus allowing theinfected cells to grow unchecked andaccumulate successive mutations, eventuallyleading to cancer.[1]Some groups of women have been found to beat a higher 'risk of developing CIN:[1][8]
Causes The cause of CIN is chronic infection of the cervix with HPV, especially infection with highrisk HPV types 16 or 18. It is thought that the high-risk HPV infections have the ability to inactivate tumor suppressor genes such as the p53 gene and the RB gene, thus allowing the infected cells to grow unchecked and accumulate successive mutations, eventually leading to cancer.[1] Some groups of women have been found to be at a higher risk of developing CIN:[1][8]
Infection with a high risk type of HPV,such as 16, 18, 31, or 33Immunodeficiency (e.g. HIV infection)Poor dietMultiple sex partnersLack of condom useCigarette smokingAdditionally, a number of risk factorshave been shown to increase anindividual's likelihood of developing CIN3/carcinoma in situ (see below):Womenwho give birth before age 17;Women whowith ≥ 1 full term pregnancies
Infection with a high risk type of HPV, such as 16, 18, 31, or 33 Immunodeficiency (e.g. HIV infection) Poor diet Multiple sex partners Lack of condom use Cigarette smoking Additionally, a number of risk factors have been shown to increase an individual's likelihood of developing CIN 3/carcinoma in situ (see below): Women who give birth before age 17;Women who with > 1 full term pregnancies
Pathophysiology+ Theearliestmicroscopic changecorrespondingto CiNisdysplasiaoftheepithelium,orsurfacelining,ofthecervixwhichisessentiallyundetectablebythewoman.Themajorityofthesechangesoccuratthesquamocolumnarjunction,ortransformationzone,an areaof unstablecervicalepitheliumthatis proneto abnormal changes.[2]CellularchangesassociatedwithHPvinfection,suchaskoilocytes,arealsocommonlyseeninCiN.WhileinfectionwithHPVisneededfordevelopmentofCiN,mostwomenwithHPvinfectiondonotdevelophigh-gradeintraepitheliallesionsor cancer.HPVis notaloneenoughcausative.[1o]Oftheover1o0differenttypesofHPV,approximately40areknowntoaffect theepithelialtissueoftheanogenitalareaandhavedifferentprobabilitiesof causingmalignantchanges
Pathophysiology ❖ The earliest microscopic change corresponding to CIN is dysplasia of the epithelium, or surface lining, of the cervix, which is essentially undetectable by the woman. The majority of these changes occur at the squamocolumnar junction, or transformation zone, an area of unstable cervical epithelium that is prone to abnormal changes.[2] Cellular changes associated with HPV infection, such as koilocytes, are also commonly seen in CIN. While infection with HPV is needed for development of CIN, most women with HPV infection do not develop high-grade intraepithelial lesions or cancer. HPV is not alone enough causative.[10] ❖ Of the over 100 different types of HPV, approximately 40 are known to affect the epithelial tissue of the anogenital area and have different probabilities of causing malignant changes
PathophysiologyFallopiantubeOvaryWombCervixVaginaTransformation zoneshowingpositionofabnormalceilsCervixVagina
Pathophysiology
DiagnosisA test for HPV called the Digene HPV test is highlyaccurate and serves as both a direct diagnosis andadjuvant to the all-important Pap smear which is ascreening device that allows for an examination ofcells but not tissue structure, needed for diagnosisA colposcopy with directed biopsy is the standardfor disease detection. Endocervical brush samplingat the time of Pap smear to detect adenocarcinomaand its precursors is necessary along withdoctor/patient vigilance on abdominal symptomsassociated with uterine and ovarian carcinoma. Thediagnosis of CIN or cervical carcinoma requires abiopsy for histological analysis
Diagnosis A test for HPV called the Digene HPV test is highly accurate and serves as both a direct diagnosis and adjuvant to the all-important Pap smear which is a screening device that allows for an examination of cells but not tissue structure, needed for diagnosis. A colposcopy with directed biopsy is the standard for disease detection. Endocervical brush sampling at the time of Pap smear to detect adenocarcinoma and its precursors is necessary along with doctor/patient vigilance on abdominal symptoms associated with uterine and ovarian carcinoma. The diagnosis of CIN or cervical carcinoma requires a biopsy for histological analysis