Vulvar intraepithelial neoplasia (VIN) refers to particular changes that can occur in the skin that covers the
vulva
The vulva (plural: vulvas or vulvae; derived from Latin for wrapper or covering) consists of the external female sex organs. The vulva includes the mons pubis (or mons veneris), labia majora, labia minora, clitoris, vestibular bulbs, vulv ...
. VIN is an
intraepithelial neoplasia, and can disappear without treatment. VINs are
benign
Malignancy () is the tendency of a medical condition to become progressively worse.
Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...
but if the changes become more severe, there is a chance of
cancer
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
developing after many years, and so it is referred to as a
precancerous condition
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 ...
.
Classification
Medically speaking, the term denotes a squamous intraepithelial
lesion
A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals.
Types
There is no designated classif ...
of the
vulva
The vulva (plural: vulvas or vulvae; derived from Latin for wrapper or covering) consists of the external female sex organs. The vulva includes the mons pubis (or mons veneris), labia majora, labia minora, clitoris, vestibular bulbs, vulv ...
that shows
dysplasia
Dysplasia is any of various types of abnormal growth or development of cells (microscopic scale) or organs ( macroscopic scale), and the abnormal histology or anatomical structure(s) resulting from such growth. Dysplasias on a mainly microscopi ...
with varying degrees of
atypia
Atypia (from Greek, ''a'' + ''typos'', without type; a condition of being irregular or nonstandard) is a histopathologic term for a structural abnormality in a cell, i.e. it is used to describe atypical cells.
Atypia can be caused by an infection ...
. The epithelial
basement membrane
The basement membrane is a thin, pliable sheet-like type of extracellular matrix that provides cell and tissue support and acts as a platform for complex signalling. The basement membrane sits between epithelial tissues including mesothelium an ...
is intact and the lesion is thus not invasive but has invasive potential.
The terminology of VIN evolved over several decades. In 1989
the Committee on Terminology,
International Society for the Study of Vulvar Disease (ISSVD) replaced older terminology such as vulvar
dystrophy
Dystrophy is the degeneration of tissue, due to disease or malnutrition, most likely due to heredity.
Types
* Muscular dystrophy
** Duchenne muscular dystrophy
** Becker's muscular dystrophy
** Myotonic dystrophy
* Reflex neurovascular d ...
,
Bowen's disease
Squamous-cell skin cancer, also known as cutaneous squamous-cell carcinoma (cSCC), is one of the main types of skin cancer along with basal cell cancer and melanoma. It usually presents as a hard lump with a scaly top but can also form an ulcer. O ...
, and Kraurosis vulvae by a new classification system for ''Epithelial Vulvar Disease'':
* Nonneoplastic epithelial disorders of vulva and mucosa:
**
Lichen sclerosus
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 (penis, vulva) and is also known as balanitis xerotica obliterans (BXO) when ...
** Squamous hyperplasia
** Other dermatoses
* Mixed neoplastic and nonneoplastic disorders
* Intraepithelial neoplasia
** Squamous vulvar intraepithelial neoplasia (VIN), previously classified as VIN 1-3:
** Non-squamous intraepithelial neoplasia
***
Extramammary Paget's disease
*** Tumors of
melanocyte
Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea),
the inner ear,
vaginal epithelium, meninges,
bones,
and hear ...
s, noninvasive
*Invasive disease (
vulvar carcinoma
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 t ...
)
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 vulvular 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.
[Sideri M, Jones RW, Wilkinson EJ, Preti M, Heller D,. Scurry J, Haefner H, Neill S. 2004 Modified Terminology, ISSVD Vulvar Oncology Subcommittee. Journal of Reproductive Medicine. 2005;50:807-10.]
Risk factors
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:
* HPV (Human Papilloma Virus)
* HSV-2 (Herpes simplex Virus - Type 2)
* Smoking
* Immunosuppression
* Chronic vulvar irritation
* Conditions such as Lichen Sclerosus
Diagnosis
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
A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a dise ...
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.
Image:Vulvar intraepithelial neoplasia3 2.jpg, Micrograph
A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a m ...
of vulvar intraepithelial neoplasia III. H&E stain
Hematoxylin and eosin stain ( or haematoxylin and eosin stain or hematoxylin-eosin stain; often abbreviated as H&E stain or HE stain) is one of the principal tissue stains used in histology. It is the most widely used stain in medical diag ...
.
Image:Differentiated vulvar intraepithelial neoplasia - intermed mag.jpg, Micrograph
A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a m ...
of differentiated vulvar intraepithelial neoplasia. H&E stain
Hematoxylin and eosin stain ( or haematoxylin and eosin stain or hematoxylin-eosin stain; often abbreviated as H&E stain or HE stain) is one of the principal tissue stains used in histology. It is the most widely used stain in medical diag ...
.
Prevention
Vaccinating girls with
HPV vaccine
Human papillomavirus (HPV) vaccines are vaccines that prevent infection by certain types of human papillomavirus (HPV). Available HPV vaccines protect against either two, four, or nine types of HPV. All HPV vaccines protect against at least HP ...
before their initial sexual contact has been claimed to reduce incidence of VIN.
References
External links
VIN at DermNet.NZ
{{DEFAULTSORT:Vulvar Intraepithelial Neoplasia
Gynaecological neoplasia
Laser medicine