| Vulvar intraepithelial neoplasia | |
|---|---|
 | |
| Micrograph of (classic) vulvar intraepithelial neoplasia III. H&E stain. | |
| Specialty | Gynecology |
Vulvar intraepithelial neoplasia (VIN) refers to particular changes that can occur in the skin that covers the vulva. VIN is an intraepithelial neoplasia, and can disappear without treatment. VINs are benign but if the changes become more severe, there is a chance of cancer developing after many years, and so it is referred to as a precancerous condition. [1]
Medically speaking, the term denotes a squamous intraepithelial lesion of the vulva that shows dysplasia with varying degrees of atypia. The epithelial basement membrane is intact and the lesion is thus not invasive but has invasive potential.
The terminology of VIN evolved over several decades. In 1989 [2] the Committee on Terminology, International Society for the Study of Vulvar Disease (ISSVD) replaced older terminology such as vulvar dystrophy, Bowen's disease, and Kraurosis vulvae by a new classification system for Epithelial Vulvar Disease:
| Source | Mild dysplasia | Moderate dysplasia | Severe dysplasia / carcinoma in situ | HPV-negative lesion with atypical keratinocytes in the basal cell layer |
|---|---|---|---|---|
| WHO 2003 [3] | Vulvar intraepithelial neoplasia (VIN) 1 | VIN 2 | VIN 3 | VIN 3 |
| WHO 2014 and ISSVD 2015 [3] | Low-grade squamous intraepithelial lesion (LSIL) | High-grade squamous intraepithelial lesion (HSIL) | Intraepithelial neoplasia, differentiated type | |
The ISSVD further revised this classification in 2004, replacing the three-grade system with a single-grade system in which only the high-grade disease is classified as VIN.
VIN is subdivided into: (Robbins Pathological Basis of Disease, 9th Ed)
Classic vulvar intraepithelial neoplasia: associated with developing into the warty and basaloid type carcinoma. This is associated with carcinogenic genotypes of HPV and/or HPV persistence factors such as cigarette smoking or immunocompromised states.
Differentiated vulvar intraepithelial neoplasia also known as VIN Simplex: is associated with vulvar dermatoses such as lichen sclerosus. It is associated with atypia of the squamous epithelium.
The exact cause of VIN is unknown. Studies are being done to determine the cause of VIN. The following factors have been associated with VIN:
The person may have no symptoms, or local symptomatology including itching, burning, and pain. The diagnosis is always based on a careful inspection and a targeted biopsy of a visible vulvar lesion.
The type and distribution of lesions varies among the two different types of VIN. In the Usual type VIN, seen more frequently in young patients, lesions tend to be multifocal over an otherwise normal vulvar skin. In the differentiated type VIN, usually seen in postmenopausal women, lesions tend to be isolated and are located over a skin with a vulvar dermatosis such as Lichen slerosus. [4]
Vaccinating girls with HPV vaccine before their initial sexual contact has been claimed to reduce incidence of VIN. [6]
The Papanicolaou test is a method of cervical screening used to detect potentially precancerous and cancerous processes in the cervix or colon. 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.
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 – which account for 70% of 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.
Penile cancer, or penile carcinoma, is a cancer that develops in the skin or tissues of the penis. Symptoms may include abnormal growth, an ulcer or sore on the skin of the penis, and bleeding or foul smelling discharge.
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.
Vulvectomy refers to a gynecological procedure in which the vulva is partly or completely removed. The procedure is usually performed as a last resort in certain cases of cancer, vulvar dysplasia, vulvar intraepithelial neoplasia, or as part of female genital mutilation. Although there may be severe pain in the groin area after the procedure, for a number of weeks, sexual function is generally still possible but limited.
Carcinoma in situ (CIS) is a group of abnormal cells. While they are a form of neoplasm, there is disagreement over whether CIS should be classified as cancer. This controversy also depends on the exact CIS in question. Some authors do not classify them as cancer, however, recognizing that they can potentially become cancer. Others classify certain types as a non-invasive form of cancer. The term "pre-cancer" has also been used.
Lichen sclerosus (LS) is a chronic, inflammatory skin disease of unknown cause which can affect any body part of any person but has a strong preference for the genitals and is also known as balanitis xerotica obliterans (BXO) when it affects the penis. Lichen sclerosus is not contagious. There is a well-documented increase of skin cancer risk in LS, potentially improvable with treatment. LS in adult age women is normally incurable, but improvable with treatment, and often gets progressively worse if not treated properly. Most males with mild or intermediate disease restricted to foreskin or glans can be cured by either medical or surgical treatment.
A precancerous condition is a condition, tumor or lesion involving abnormal cells which are associated with an increased risk of developing into cancer. Clinically, precancerous conditions encompass a variety of abnormal tissues with an increased risk of developing into cancer. Some of the most common precancerous conditions include certain colon polyps, which can progress into colon cancer, monoclonal gammopathy of undetermined significance, which can progress into multiple myeloma or myelodysplastic syndrome. and cervical dysplasia, which can progress into cervical cancer. Bronchial premalignant lesions can progress to squamous cell carcinoma of the lung.
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.
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.
Interferon regulatory factor 6 also known as IRF6 is a protein that in humans is encoded by the IRF6 gene.
Vulvar cancer is a cancer of the vulva, the outer portion of the female genitals. It most commonly affects the labia majora. Less often, the labia minora, clitoris, or vaginal glands are affected. Symptoms include a lump, itchiness, changes in the skin, or bleeding from the vulva.
HspE7 is an investigational therapeutic vaccine candidate being developed by Nventa Biopharmaceuticals for the treatment of precancerous and cancerous lesions caused by the human papillomavirus (HPV). HspE7 uses recombinant DNA technology to covalently fuse a heat shock protein (Hsp) to a target antigen, thereby stimulating cellular immune system responses to specific diseases. HspE7 is a patented construct consisting of the HPV Type 16 E7 protein and heat shock protein 65 (Hsp65) and is currently the only candidate using Hsp technology to target the over 20 million Americans already infected with HPV.
High-grade prostatic intraepithelial neoplasia (HGPIN) is an abnormality of prostatic glands and believed to precede the development of prostate adenocarcinoma.
Bowenoid papulosis is a cutaneous condition characterized by the presence of pigmented verrucous papules on the body of the penis. They are associated with human papillomavirus, the causative agent of genital warts. The lesions have a typical dysplastic histology and are generally considered benign, although a small percentage will develop malignant characteristics.
Epithelial dysplasia, a term becoming increasingly referred to as intraepithelial neoplasia, is the sum of various disturbances of epithelial proliferation and differentiation as seen microscopically. Individual cellular features of dysplasia are called epithelial atypia.
Conjunctival squamous cell carcinoma and corneal intraepithelial neoplasia comprise ocular surface squamous neoplasia (OSSN). SCC is the most common malignancy of the conjunctiva in the US, with a yearly incidence of 1–2.8 per 100,000. Risk factors for the disease are exposure to sun, exposure to UVB, and light-colored skin. Other risk factors include radiation, smoking, HPV, arsenic, and exposure to polycyclic hydrocarbons.
A vulvar disease is a particular abnormal, pathological condition that affects part or all of the vulva. Several pathologies are defined. Some can be prevented by vulvovaginal health maintenance.
Vulvar tumors are those neoplasms of the vulva. Vulvar and vaginal neoplasms make up a small percentage (3%) of female genital cancers. They can be benign or malignant. Vulvar neoplasms are divided into cystic or solid lesions and other mixed types. Vulvar cancers are those malignant neoplasms that originate from vulvar epithelium, while vulvar sarcomas develop from non-epithelial cells such as bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Epithelial and mesenchymal tissue are the origin of vulvar tumors.
The International Society for the Study of Vulvovaginal Disease (ISSVD) is a non-profit organization that was founded in 1970 at the Sixth World Congress of the International Federation of Obstetricians and Gynecologists (FIGO) in New York City. It is composed of health care professionals from different areas, including, gynecologists, dermatologists, general practitioners, physiotherapist, nurse practitioners, etc. devoted to the study, investigation, and treatment of vulvovaginal diseases.