Pap test

Last updated
Papanicolaou test
High-grade squamous intraepithelial lesion.jpg
High-grade squamous intraepithelial lesion
Specialty gynaecology
ICD-9-CM 795.00
MeSH D014626
MedlinePlus 003911

The Papanicolaou test (abbreviated as Pap test, also known as Pap smear (AE), [1] cervical smear (BE), cervical screening (BE), [2] or smear test (BE)) is a method of cervical screening used to detect potentially precancerous and cancerous processes in the cervix (opening of the uterus or womb) or, more rarely, anus (in both men and women). [3] Abnormal findings are often followed up by more sensitive diagnostic procedures and, if warranted, interventions that aim to prevent progression to cervical cancer. The test was independently invented in the 1920s by the Greek physician Georgios Papanikolaou and named after him. A simplified version of the test was introduced by the Canadian obstetrician Anna Marion Hilliard in 1957.

Contents

A Pap smear is performed by opening the vagina with a speculum and collecting cells at the outer opening of the cervix at the transformation zone (where the outer squamous cervical cells meet the inner glandular endocervical cells), using an Ayre spatula or a cytobrush. The collected cells are examined under a microscope to look for abnormalities. The test aims to detect potentially precancerous changes (called cervical intraepithelial neoplasia (CIN) or cervical dysplasia; the squamous intraepithelial lesion system (SIL) is also used to describe abnormalities) caused by human papillomavirus, a sexually transmitted DNA virus. The test remains an effective, widely used method for early detection of precancer and cervical cancer. While the test may also detect infections and abnormalities in the endocervix and endometrium, it is not designed to do so.

Guidelines on when to begin Pap smear screening are varied, but usually begin in adulthood. Guidelines on frequency vary from every three to five years. [4] [5] [6] If results are abnormal, and depending on the nature of the abnormality, the test may need to be repeated in six to twelve months. [7] If the abnormality requires closer scrutiny, the patient may be referred for detailed inspection of the cervix by colposcopy, which magnifies the view of the cervix, vagina and vulva surfaces. The person may also be referred for HPV DNA testing, which can serve as an adjunct to Pap testing. In some countries, viral DNA is checked for first, before checking for abnormal cells. [8] Additional biomarkers that may be applied as ancillary tests with the Pap test are evolving. [9]

Medical uses

Summary of reasons for testing
patient's characteristicindicationrationale
under age 21, regardless of sexual historyno testmore harms than benefits [10]
age 20–25 until age 50–60test every 3–5 years if results normalbroad recommendation [11]
over age 65; history of normal testsno further testingrecommendation of USPSTF, ACOG, ACS and ASCP; [5] [12] [13]
had total hysterectomy for non-cancer disease – cervix removedno further testingharms of screening after hysterectomy outweigh the benefits [10]
had partial hysterectomy – cervix remainscontinue testing as normal
has received HPV vaccine continue testing as normalvaccine does not cover all cancer-causing types of HPV [11]
history of endometrial cancer, with history of hysterectomydiscontinue routine testing [14] test no longer effective and likely to give false positive [14]

Screening guidelines vary from country to country. In general, screening starts about the age of 20 or 25 and continues until about the age of 50 or 60. [12] Screening is typically recommended every three to five years, as long as results are normal. [11]

American Congress of Obstetricians and Gynecologists (ACOG) and others recommend starting screening at age 21. [5] [15] Many other countries wait until age 25 or later to start screening. For instance, some parts of Great Britain start screening at age 25. ACOG's general recommendation is that people with female reproductive organs age 30–65 have an annual well-woman examination, that they not get annual Pap tests, and that they do get Pap tests at three to five year intervals. [16]

HPV is passed through skin to skin contact; sex does not have to occur, although it is a common way for it to spread. [17] It takes an average of a year, but can take up to four years, for a person's immune system to clear the initial infection. Screening during this period may show this immune reaction and repair as mild abnormalities, which are usually not associated with cervical cancer, but could cause the patient stress and result in further tests and possible treatment. Cervical cancer usually takes time to develop, so delaying the start of screening a few years poses little risk of missing a potentially precancerous lesion. For instance, screening people under age 25 does not decrease cancer rates under age 30. [18]

HPV can be transmitted in sex between females, so those who have only had sex with other females should be screened, although they are at somewhat lower risk for cervical cancer. [19]

Guidelines on frequency of screening vary—typically every three to five years for those who have not had previous abnormal smears. [11] Some older recommendations suggested screening as frequently as every one to two years, however there is little evidence to support such frequent screening; annual screening has little benefit but leads to greatly increased cost and many unnecessary procedures and treatments. [5] It has been acknowledged since before 1980 that most people can be screened less often. [20] In some guidelines, frequency depends on age; for instance in Great Britain, screening is recommended every three years for women under 50, and every five years for those over. [21]

Screening should stop at about age 65 unless there is a history of abnormal test result or disease. There is probably no benefit in screening people aged 60 or over whose previous tests have been negative. [13] If a woman's last three Pap results were normal, she can discontinue testing at age 65, according to the USPSTF, ACOG, ACS, and ASCP; [5] England's NHS says 64. There is no need to continue screening after a complete hysterectomy for benign disease.

Pap smear screening is still recommended for those who have been vaccinated against HPV [11] since the vaccines do not cover all HPV types that can cause cervical cancer. Also, the vaccine does not protect against HPV exposure before vaccination. [22]

Those with a history of endometrial cancer should discontinue routine Pap tests after hysterectomy. [14] [23] Further tests are unlikely to detect recurrence of cancer but do bring the risk of giving false positive results, which would lead to unnecessary further testing. [14]

More frequent Pap smears may be needed to follow up after an abnormal Pap smear, after treatment for abnormal Pap or biopsy results, or after treatment of cancer (cervical, anal, etc.). [24]

Effectiveness

The Pap test, when combined with a regular program of screening and appropriate follow-up, can reduce cervical cancer deaths by up to 80%. [11]

Failure of prevention of cancer by the Pap test can occur for many reasons, including not getting regular screening, lack of appropriate follow-up of abnormal results, and sampling and interpretation errors. [25] In the US, over half of all invasive cancers occur in females who have never had a Pap smear; an additional 10 to 20% of cancers occur in those who have not had a Pap smear in the preceding five years.[ citation needed ] About one-quarter of US cervical cancers were in people who had an abnormal Pap smear but did not get appropriate follow-up (patient did not return for care, or clinician did not perform recommended tests or treatment).[ citation needed ]

Adenocarcinoma of the cervix has not been shown to be prevented by Pap smears. [25] In the UK, which has a Pap smear screening program, adenocarcinoma accounts for about 15% of all cervical cancers. [26]

Estimates of the effectiveness of the United Kingdom's call and recall system vary widely, but it may prevent about 700 deaths per year in the UK. [27]

Multiple studies have performed sensitivity and specificity analyses on Pap smears. Sensitivity analysis captures the ability of Pap smears to correctly identify women with cervical cancer. Various studies have revealed the sensitivity of Pap smears to be between 47.19 - 55.5%. [28] [29] [30] Specificity analysis captures the ability of Pap smears to correctly identify women without cervical cancer. Various studies have revealed the specificity of Pap smears to be between 64.79 - 96.8%. [28] [29] [30] While Pap smears may not be entirely accurate, they remain one of the most effective cervical cancer prevention tools. Pap smears may be supplemented with HPV DNA testing.[ citation needed ]

Results

In screening a general or low-risk population, most Pap results are normal.

In the United States, about 2–3 million abnormal Pap smear results are found each year. [31] Most abnormal results are mildly abnormal (ASC-US (typically 2–5% of Pap results) or low-grade squamous intraepithelial lesion (LSIL) (about 2% of results)), indicating HPV infection.[ citation needed ] Although most low-grade cervical dysplasias spontaneously regress without ever leading to cervical cancer, dysplasia can serve as an indication that increased vigilance is needed.

In a typical scenario, about 0.5% of Pap results are high-grade SIL (HSIL), and less than 0.5% of results indicate cancer; 0.2 to 0.8% of results indicate Atypical Glandular Cells of Undetermined Significance (AGC-NOS).[ citation needed ]

As liquid-based preparations (LBPs) become a common medium for testing, atypical result rates have increased. The median rate for all preparations with low-grade squamous intraepithelial lesions using LBPs was 2.9% in 2006, compared with a 2003 median rate of 2.1%. Rates for high-grade squamous intraepithelial lesions (median, 0.5%) and atypical squamous cells have changed little. [32]

Abnormal results are reported according to the Bethesda system. [33] They include: [31]

Endocervical and endometrial abnormalities can also be detected, as can a number of infectious processes, including yeast, herpes simplex virus and trichomoniasis. However it is not very sensitive at detecting these infections, so absence of detection on a Pap does not mean absence of the infection.[ citation needed ]

Pregnancy

Pap tests can usually be performed during pregnancy up to at least 24 weeks of gestational age. [34] Pap tests during pregnancy have not been associated with increased risk of miscarriage. [34] An inflammatory component is commonly seen on Pap smears from pregnant women [35] and does not appear to be a risk for subsequent preterm birth. [36]

After childbirth, it is recommended to wait 12 weeks before taking a Pap test because inflammation of the cervix caused by the birth interferes with test interpretation. [37]

In transgender individuals

Transgender men are also typically at risk for HPV due to retention of the uterine cervix in the majority of individuals in this subgroup. [38] [39] As such, professional guidelines recommend that transgender men be screened routinely for cervical cancer using methods such as Pap smear, identical to the recommendations for cisgender women. [40]

However, transgender men have lower rates of cervical cancer screening than cisgender women. [41] Many transgender men report barriers to receiving gender-affirming healthcare, [42] [43] including lack of insurance coverage and stigma/discrimination [44] [45] during clinical encounters, and may encounter provider misconceptions regarding risk in this population for cervical cancer. Pap smears may be presented to patients as non-gendered screening procedures for cancer rather than one specific for examination of the female reproductive organs. Pap smears may trigger gender dysphoria in patients and gender-neutral language can be used when explaining the pathogenesis of cancer due to infection, emphasizing the pervasiveness of HPV infection regardless of gender. [46]

Transgender women who have not had vaginoplasties are not at risk of developing cervical cancer because they do not have cervices. Transgender women who have had vaginoplasties and have a neo-cervix or neo-vagina have a small chance of developing cancer, according to the Canadian Cancer Society. [47] Surgeons typically use penile skin to create the new vagina and cervix, which can contract HPV and lead to penile cancer, although it is considerably rarer than cervical cancer. [48] Because the risk of this kind of cancer is so low, cervical cancer screening is not routinely offered for those with a neo-cervix. [49] [39] [50] [48]

Procedure

Sample collection for thin-prep-cytology from the cervix uteri of a 39-years-old multiparous woman (4 pregnancies). The cervical brush is visible just before entering the cervix uteri. Taking pap-smear 1.png
Sample collection for thin-prep-cytology from the cervix uteri of a 39-years-old multiparous woman (4 pregnancies). The cervical brush is visible just before entering the cervix uteri.

According to the CDC, intercourse, douching, and the use of vaginal medicines or spermicidal foam should be avoided for 2 days before the test. [51] A number of studies have shown that using a small amount of water-based gel lubricant does not interfere with, obscure, or distort the Pap smear. Further, cytology is not affected, nor are some STD testing. [52] The CDC states that Pap smears can be performed during menstruation. [51] However, the NHS recommends against cervical screening during, or in the 2 days before and after, menstruation. [53] Pap smears can be performed during menstruation, especially if the physician is using a liquid-based test; however if bleeding is extremely heavy, endometrial cells can obscure cervical cells, and if this occurs the test may need to be repeated in 6 months. [54]

Pap smears begin with the insertion of a speculum into the vagina, which spreads the vagina open and allows access to the cervix. The health care provider then collects a sample of cells from the outer opening or external os of the cervix by scraping it with either a spatula or brush. [55]

Obtaining a Pap smear should not cause much pain, [56] but may be uncomfortable. [57] Conditions such as vaginismus, vulvodynia, or cervical stenosis can cause insertion of the speculum to be painful. [58] [59]

In a conventional Pap smear, the cells are placed on a glass slide and taken to the laboratory to be checked for abnormalities. [60]

A plastic-fronded broom is sometimes used in place of the spatula or brush. The broom is not as good a collection device, since it is much less effective at collecting endocervical material than the spatula and brush. [61] The broom is used more frequently with the advent of liquid-based cytology, although either type of collection device may be used with either type of cytology.

The sample is stained using the Papanicolaou technique, in which tinctorial dyes and acids are selectively retained by cells. Unstained cells cannot be seen adequately with a light microscope. Papanicolaou chose stains that highlighted cytoplasmic keratinization, which actually has almost nothing to do with the nuclear features used to make diagnoses now.[ citation needed ]

A single smear has an area of 25 x 50 mm and contains a few hundred thousand cells on average. Screening with light microscopy is first done on low (10x) power and then switched to higher (40x) power upon viewing suspicious findings. Cells are analyzed under high power for morphologic changes indicative of malignancy (including enlarged and irregularly shaped nucleus, an increase in nucleus to cytoplasm ratio, and more coarse and irregular chromatin). Approximately 1,000 fields of view are required on 10x power for screening of a single sample, which takes on average 5 to 10 minutes. [62]

In some cases, a computer system may prescreen the slides, indicating those that do not need examination by a person or highlighting areas for special attention. The sample is then usually screened by a specially trained and qualified cytotechnologist using a light microscope. The terminology for who screens the sample varies according to the country; in the UK, the personnel are known as cytoscreeners, biomedical scientists (BMS), advanced practitioners and pathologists. The latter two take responsibility for reporting the abnormal sample, which may require further investigation.[ citation needed ]

Automated analysis

In the last decade, there have been successful attempts to develop automated, computer image analysis systems for screening. [63] Although, on the available evidence automated cervical screening could not be recommended for implementation into a national screening program, a recent NHS Health technology appraisal concluded that the 'general case for automated image analysis ha(d) probably been made'. [64] Automation may improve sensitivity and reduce unsatisfactory specimens. [65] Two systems have been approved by the FDA and function in high-volume reference laboratories, with human oversight.[ citation needed ]

Types of screening

Transformation zone types, determining the Pap test location: Type 1: Completely ectocervical. Type 2: Endocervical component but fully visible. Type 3: Endocervical component, not fully visible. Transformation zone types.png
Transformation zone types, determining the Pap test location:
Type 1: Completely ectocervical.
Type 2: Endocervical component but fully visible.
Type 3: Endocervical component, not fully visible.
Cervix in relation to upper part of vagina and posterior portion of uterus. Gray1167.svg
Cervix in relation to upper part of vagina and posterior portion of uterus.
Squamous metaplasia of the cervix, with typical features. Pap stain. Cytology of cervical squamous metaplasia.png
Squamous metaplasia of the cervix, with typical features. Pap stain.

Pap tests commonly examine epithelial abnormalities, such as metaplasia, dysplasia, or borderline changes, all of which may be indicative of CIN. Nuclei will stain dark blue, squamous cells will stain green and keratinised cells will stain pink/ orange. Koilocytes may be observed where there is some dyskaryosis (of epithelium). The nucleus in koilocytes is typically irregular, indicating possible cause for concern; requiring further confirmatory screens and tests.

In addition, human papillomavirus (HPV) test may be performed either as indicated for abnormal Pap results, or in some cases, dual testing is done, where both a Pap smear and an HPV test are done at the same time (also called Pap co-testing). [67]

Practical aspects

The endocervix may be partially sampled with the device used to obtain the ectocervical sample, but due to the anatomy of this area, consistent and reliable sampling cannot be guaranteed. Since abnormal endocervical cells may be sampled, those examining them are taught to recognize them.[ citation needed ]

The endometrium is not directly sampled with the device used to sample the ectocervix. Cells may exfoliate onto the cervix and be collected from there, so as with endocervical cells, abnormal cells can be recognised if present but the Pap test should not be used as a screening tool for endometrial malignancy.[ citation needed ]

In the United States, a Pap test itself costs $20 to $30, but the costs for Pap test visits can cost over $1,000, largely because additional tests are added that may or may not be necessary. [68]

History

The test was invented by and named after the Greek doctor Georgios Papanikolaou, who started his research in 1923. [69] Aurel Babeș independently made similar discoveries in 1927. [70] [71] However, Babeș' method was radically different from Papanikolaou's. [69] [72]

The Pap test was finally recognized only after a leading article in the American Journal of Obstetrics and Gynecology in 1941 by Papanikolaou and Herbert F. Traut, an American gynecologist. [69] [73] A monograph titled Diagnosis of Uterine Cancer by the Vaginal Smear that they published contained drawings of the various cells seen in patients with no disease, inflammatory conditions, and preclinical and clinical carcinoma. [69] The monograph was illustrated by Hashime Murayama, who later became a staff illustrator with the National Geographic Society. [69] Both Papanikolaou and his wife, Andromachi Papanikolaou, dedicated the rest of their lives to teaching the technique to other physicians and laboratory personnel. [69]

Experimental techniques

In the developed world, cervical biopsy guided by colposcopy is considered the "gold standard" for diagnosing cervical abnormalities after an abnormal Pap smear. Other techniques such as triple smear are also done after an abnormal Pap smear. [74] The procedure requires a trained colposcopist and can be expensive to perform. However, Pap smears are very sensitive and some negative biopsy results may represent undersampling of the lesion in the biopsy, so negative biopsy with positive cytology requires careful follow-up. [75]

Experimental visualization techniques use broad-band light (e.g., direct visualization, speculoscopy, cervicography, visual inspection with acetic acid or with Lugol's, and colposcopy) and electronic detection methods (e.g., Polarprobe and in vivo spectroscopy). These techniques are less expensive and can be performed with significantly less training. They do not perform as well as Pap smear screening and colposcopy. At this point, these techniques have not been validated by large-scale trials and are not in general use.[ citation needed ]

Implementation by country

Australia

Australia has used the Pap test as part of its cervical screening program since its implementation in 1991 which required women past the age of 18 be tested every two years. [76] In December 2017 Australia discontinued its use of the Pap test and replaced it with a new HPV test that is only required to be conducted once every five years from the age of 25. [77] Medicare covers the costs of testing; however, if a patient's doctor does not allow bulk billing, they may have to pay for the appointment and then claim the Medicare rebate. [78]

Taiwan

Free Pap tests were offered from 1974–1984 before being replaced by a system in which all women over the age of 30 could have the cost of their Pap test reimbursed by the National Health Insurance in 1995. [79] This policy was still ongoing in 2018 and encouraged women to screen at least every three years. [80]

Despite this, the number of people receiving Pap tests remain lower than countries like Australia. Some believe this is due to a lack of awareness regarding the test and its availability. It has also been found that women who have chronic diseases or other reproductive diseases are less likely to receive the test. [81] [82] [83]

England

As of 2020 the NHS maintains a cervical screening program in which women between the age of 25–49 are invited for a smear test every three years, and women past 50 every five years. Much like Australia, England uses a HPV test before examining cells that test positive using the Pap test. [84] The test is free as part of the national cervical screening program. [85]

Coccoid bacteria

The finding of coccoid bacteria on a Pap test is of no consequence with otherwise normal test findings and no infectious symptoms. However, if there is enough inflammation to obscure the detection of precancerous and cancerous processes, it may indicate treatment with a broad-spectrum antibiotic for streptococci and anaerobic bacteria (such as metronidazole and amoxicillin) before repeating the smear. Alternatively, the test will be repeated at an earlier time than it would otherwise. [86] If there are symptoms of vaginal discharge, bad odor or irritation, the presence of coccoid bacteria also may indicate treatment with antibiotics as per above. [86]

Related Research Articles

<span class="mw-page-title-main">Cervix</span> Lower part of the uterus in the female reproductive system

The cervix or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the time of Hippocrates, over 2,000 years ago. The cervix is approximately 4 cm long with a diameter of approximately 3 cm and tends to be described as a cylindrical shape, although the front and back walls of the cervix are contiguous. The size of the cervix changes throughout a woman's life cycle. For example, during the fertile years of a woman's reproductive cycle, females tend to have a larger cervix vis á vis postmenopausal females; likewise, females who have produced offspring have a larger sized cervix than females who have not produced offspring.

<span class="mw-page-title-main">Cervical cancer</span> Cancer arising from the cervix

Cervical cancer is a cancer arising from the cervix or in the any layer of the wall of the cervix. It is due to the abnormal growth of cells that have the ability to invade or spread to other parts of the body. Early on, typically no symptoms are seen. Later symptoms may include abnormal vaginal bleeding, pelvic pain or pain during sexual intercourse. While bleeding after sex may not be serious, it may also indicate the presence of cervical cancer.

<span class="mw-page-title-main">Georgios Papanikolaou</span> Greek pathologist (1883–1962)

Georgios Nikolaou Papanikolaou was a Greek physician, zoologist and microscopist who was a pioneer in cytopathology and early cancer detection, and inventor of the pap smear for detection of cervical cancer.

<span class="mw-page-title-main">Human papillomavirus infection</span> Human disease

Human papillomavirus infection is caused by a DNA virus from the Papillomaviridae family. Many HPV infections cause no symptoms and 90% resolve spontaneously within two years. In some cases, an HPV infection persists and results in either warts or precancerous lesions. These lesions, depending on the site affected, increase the risk of cancer of the cervix, vulva, vagina, penis, anus, mouth, tonsils, or throat. Nearly all cervical cancer is due to HPV, and two strains – HPV16 and HPV18 – account for 70% of all cases. HPV16 is responsible for almost 90% of HPV-positive oropharyngeal cancers. Between 60% and 90% of the other cancers listed above are also linked to HPV. HPV6 and HPV11 are common causes of genital warts and laryngeal papillomatosis.

<span class="mw-page-title-main">Cytopathology</span> A branch of pathology that studies and diagnoses diseases on the cellular level

Cytopathology is a branch of pathology that studies and diagnoses diseases on the cellular level. The discipline was founded by George Nicolas Papanicolaou in 1928. Cytopathology is generally used on samples of free cells or tissue fragments, in contrast to histopathology, which studies whole tissues. Cytopathology is frequently, less precisely, called "cytology", which means "the study of cells".

<span class="mw-page-title-main">Colposcopy</span> Medical examination of the cervix

Colposcopy is a medical diagnostic procedure to visually examine the cervix as well as the vagina and vulva using a colposcope.

<span class="mw-page-title-main">Anal cancer</span> Medical condition

Anal cancer is a cancer which arises from the anus, the distal opening of the gastrointestinal tract. Symptoms may include bleeding from the anus or a lump near the anus. Other symptoms may include pain, itchiness, or discharge from the anus. A change in bowel movements may also occur.

<span class="mw-page-title-main">Cervical intraepithelial neoplasia</span> Medical condition

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. More specifically, CIN refers to the potentially precancerous transformation of cells of the cervix.

<span class="mw-page-title-main">Papanicolaou stain</span> Histological staining method

Papanicolaou stain is a multichromatic (multicolored) cytological staining technique developed by George Papanicolaou in 1942. The Papanicolaou stain is one of the most widely used stains in cytology, where it is used to aid pathologists in making a diagnosis. Although most notable for its use in the detection of cervical cancer in the Pap test or Pap smear, it is also used to stain non-gynecological specimen preparations from a variety of bodily secretions and from small needle biopsies of organs and tissues. Papanicolaou published three formulations of this stain in 1942, 1954, and 1960.

<span class="mw-page-title-main">Koilocyte</span> Type of cell that has been changed by HPV

A koilocyte is a squamous epithelial cell that has undergone a number of structural changes, which occur as a result of infection of the cell by human papillomavirus (HPV). Identification of these cells by pathologists can be useful in diagnosing various HPV-associated lesions.

Aurel A. Babeș was a Romanian scientist and one of the discoverers of the vaginal smear as screening test for cervical cancer.

<span class="mw-page-title-main">Cervical canal</span> Canal of the uterine cervix

The cervical canal is the spindle-shaped, flattened canal of the cervix which connects the vagina to the main cavity of the uterus in most mammals.

An anal Pap smear is the anal counterpart of the cervical Pap smear. It is used for the early detection of anal cancer. Some types of human papillomavirus (HPV) can cause anal cancer. Other HPV types cause anogenital warts. Cigarette smokers, men who have sex with men, individuals with a history of immunosuppression and women with a history of cervical, vaginal and vulval cancer are at increased risk of getting anal cancer. Vaccination against HPV before initial sexual exposure can reduce the risk of anal cancer.

The Bethesda system (TBS), officially called The Bethesda System for Reporting Cervical Cytology, is a system for reporting cervical or vaginal cytologic diagnoses, used for reporting Pap smear results. It was introduced in 1988 and revised in 1991, 2001, and 2014. The name comes from the location of the conference, sponsored by the National Institutes of Health, that established the system.

<span class="mw-page-title-main">Squamous intraepithelial lesion</span> Abnormal cell growth in the cervix

A squamous intraepithelial lesion (SIL) is an abnormal growth of epithelial cells on the surface of the cervix, commonly called squamous cells. This condition can lead to cervical cancer, but can be diagnosed using a Pap smear or a colposcopy. It can be treated by using methods that remove the abnormal cells, allowing normal cells to grow in their place. In the Bethesda system, the cytology can be graded as LSIL or HSIL.

<span class="mw-page-title-main">Cervical cancer staging</span> Medical condition

Cervical cancer staging is the assessment of cervical cancer to determine the extent of the spread of cancer beyond the cervix. This is important for determining how serious the cancer is and to create the best treatment plan.

<span class="mw-page-title-main">Cervical screening</span> Type of medical screening

Cervical cancer screening is a medical screening test designed to identify risk of cervical cancer. Cervical screening may involve looking for viral DNA, and/or to identify abnormal, potentially precancerous cells within the cervix as well as cells that have progressed to early stages of cervical cancer. One goal of cervical screening is to allow for intervention and treatment so abnormal lesions can be removed prior to progression to cancer. An additional goal is to decrease mortality from cervical cancer by identifying cancerous lesions in their early stages and providing treatment prior to progression to more invasive disease.

<span class="mw-page-title-main">Liquid-based cytology</span> Method of preparing samples for cytopathology

Liquid-based cytology is a method of preparing samples for examination in cytopathology. The sample is collected, normally by a small brush, in the same way as for a conventional smear test, but rather than the smear being transferred directly to a microscope slide, the sample is deposited into a small bottle of preservative liquid. At the laboratory, the liquid is treated to remove other elements such as mucus before a layer of cells is placed on a slide.

Microglandular hyperplasia (MGH) of the cervix is an epithelial benign abnormality (lesion) associated with gland proliferation. It can terminate in mature squamous metaplasia, and it is suspected reserve cells are involved in this process, perhaps in the form of reserve cell hyperplasia with glandular differentiation.

Andromachi "Mary" Mavrogeni Papanikolaou was a Greek laboratory technician and the wife of Georgios Papanikolaou, the Greek pathologist who independently invented the pap test. For 21 years, Mary Papanikolaou volunteered to have her cervix sampled and smeared by her husband to help with his efforts to create the pap test, which has been shown to reduce cervical cancer deaths by up to 80 percent.

References

Notes
  1. ↑ "Pap Smear: MedlinePlus Lab Test Information". medlineplus.gov. Retrieved 2018-11-07.
  2. ↑ "Cervical Screening". NHS. 2017-10-20. Retrieved 2018-09-04.
  3. ↑ Lindsey, Kimberley; DeCristofaro, Claire; James, Janet (August 2009). "Anal Pap smears: Should we be doing them?". Journal of the American Academy of Nurse Practitioners. 21 (8): 437–443. doi:10.1111/j.1745-7599.2009.00433.x.
  4. ↑ Moyer, VA; U.S. Preventive Services Task, Force (Jun 19, 2012). "Screening for cervical cancer: U.S. Preventive Services Task Force recommendation statement". Annals of Internal Medicine. 156 (12): 880–91, W312. doi:10.7326/0003-4819-156-12-201206190-00424. PMID   22711081. S2CID   36965456.
  5. 1 2 3 4 5 Saslow, Debbie; Solomon, Diane; Lawson, Herschel W.; Killackey, Maureen; Kulasingam, Shalini L.; Cain, Joanna M.; Garcia, Francisco A. R.; Moriarty, Ann T.; Waxman, Alan G.; Wilbur, David C.; Wentzensen, Nicolas; Downs, Levi S.; Spitzer, Mark; Moscicki, Anna-Barbara; Franco, Eduardo L.; Stoler, Mark H.; Schiffman, Mark; Castle, Philip E.; Myers, Evan R. (July 2012). "American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology Screening Guidelines for the Prevention and Early Detection of Cervical Cancer". Journal of Lower Genital Tract Disease. 16 (3): 175–204. doi:10.1097/LGT.0b013e31824ca9d5. PMC   3915715 . PMID   22418039.
  6. ↑ American Cancer Society. (2010). Detailed Guide: Cervical Cancer. Can cervical cancer be prevented? Retrieved August 8, 2011.
  7. ↑ The American College of Obstetricians and Gynecologists (2009). "ACOG Education Pamphlet AP085 – The Pap Test". Washington, DC. Archived from the original on June 15, 2010. Retrieved June 5, 2010.
  8. ↑ "Cervical cancer screening in England to use 'more accurate' viral DNA test". Cancer Research UK - Cancer News. 2016-07-05. Retrieved 2023-08-10.
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