Compound nevi with marked lentiginous proliferation of melanocytes at dermoepidermal junction, extending at least 3 rete ridges beyond lateral margins of dermal component. To determine the reliability of the histopathologic diagnosis of melanocytic dysplasia among diverse dermatopathologists who had no joint training, agreed to abide by predetermined criteria, and who were provided reference photomicrographs illustrative of the criteria. Dysplastic nevi, also known as atypical moles, are unusual or atypical and benign. A pragmatic approach to atypical pigmented lesions that pose problems for clinicians and pathologists dr patricia renaut, qml pathology inside this issue.
Dysplastic naevian alternative view dysplastic naevian alternative view cook, m. The dysplastic nevus syndrome jama dermatology jama. Their diagnosis is reproducible if criteria and thresholds are agreed upon. Current data suggest no further treatment is necessary for dysplastic naevi with low grade dysplasia previous moderately dysplastic naevi in which there are clear histologic margins and no pigment evident clinically unless there was a high level of prebiopsy clinical. Atypical pigmented lesions primary cutaneous lymphoma surgical skin audit dysglycaemic states and diabetes mellitus dysplastic naevi the dysplastic naevus continues to be a subject of. They tend to be larger than nondysplastic nevi, typically exhibit some degree of asymmetry, and have somewhat irregular illdefined borders fig. The dysplastic nevus panel article pdf available in archives of dermatology 38.
Reliability of the histopathologic diagnosis of melanocytic dysplasia. Dysplastic nevus syndrome an overview sciencedirect topics. Dysplastic naevi are clinically atypical and histologi cally are characterized by architectural. Histopathology skin compound clarks nevus dysplastic nevus this feature is not available right now. Though benign, they are worth more of your attention because individuals with atypical moles are at increased risk for melanoma, a dangerous skin cancer an atypical mole can occur anywhere on the body. People who have dysplastic nevi usually also have an. In the appropriate clinically setting dysplastic atypical, clark melanocytic nevi are cutaneous markers for the development of familial and nonfamilial melanomas. Sitespecific histopathology features have been reported for acral, auricular, flexural, and genital melanocytic nevi, however, to the best of our knowledge, site and sexspecific histology of dysplastic nevi on the lower leg between knee and ankle of women dnlw has not been. A stratified random sample of 112 melanocytic tumors were chosen. Grade of atypia in dysplastic nevi and relationship with dermal. Just like actinic keratosis does not do justice to the potential dangerous nature of a lesion that is an incipient squamous cell carcinoma, the term dysplastic nevus implies a more serious nature to a wholly benign lesion. However, it is not uncommon for dysplastic nevi to form on the scalp, breasts, or legs.
Pdf histopathologic recognition and grading of dysplastic. A large number of nevi often more than 50, some of which are atypical on visual examination. Dysplastic nevi can form anywhere on the body, but are often found in areas of the body that are frequently exposed to the sun. Dysplastic nevi are usually compound nevi with peripheral lentiginous and junctional activity and random cytological atypia in the epidermal component. Sun exposure is a causative factor, particularly in childhood. Histopathologic recognition and grading of dysplastic melanocytic nevi. I got a call from his office today saying i needed to come back for more to be removed because the biopsy said it was a severe dysplastic nevus with some pre cancerous cells. The majority of moles appear during the first two decades of a persons life, with about one in every 100. Histopathologic recognition and grading of dysplastic. Although atypical nevi are benign lesions, they are strong phenotypic markers of an increased risk of melanoma, especially in individuals with numerous nevi andor a family history of melanoma. Histopathological aspects of dysplastic nevi springerlink. Modernday dermatology also employs electron microscopy and immunohistochemistry in the diagnosis of exclusion. Another thing that helps distinguish a benign mole from a dysplastic. A melanocytic nevus also known as nevocytic nevus, nevuscell nevus and commonly as a mole is a type of melanocytic tumor that contains nevus cells.
This syndrome was previously called dysplastic nevus syndrome. Since initially being reported as histologic lesions observed in melanomaprone families, there has been considerable debate about the definition of dysplastic nevi, the histologic and clinical criteria used to. At my regular full body exam, my dermatologist dermatopathologist mohs surgeon took off a small mole on my buttock. A dysplastic nevomelanocytic nevus dn can be defined as a localized proliferation of melanocytes with cytological and architectural atypia. The entity mildly dysplastic naevus has been removed from the world health organisations classification of dysplastic naevi.
Acquired melanoyctic naevus or mole is a common benign tumour, usually appearing during childhood and adolescence. Immunohistochemical expression of p16 in melanocytic lesions. I believe it would be reasonable to change the name dysplastic nevus. A practical approach to the diagnosis of melanocytic lesions. Some sources equate the term mole with melanocytic nevus, but there are also sources that equate the term mole with any nevus form. Ackerman criticized the usage and inconsistency of the term dysplasia in pathology, and argued that features of the clinically atypical nevus and the histologic dn. Lesions evolve with age, the initial lesion being macular with nests of proliferating. Dysplastic atypical nevus syndrome includes familial originally known as bk mole syndrome and sporadic occurrence of multiple dysplastic nevi in. The distinctive appearance of an atypical mole generally includes irregular or indistinct borders, or nonuniform coloring that can range from pink to dark brown. Division of pathology and laboratory medicine, medical school. Pdf reliability of the histopathologic diagnosis of.
Dysplastic nevus originally proposed by clarks group is a key entity of the. Although dysplastic naevi are most often encountered, cytological atypia may be. Dysplastic or atypical nevi are acquired nevi that are 5 mm in diameter and have irregular or variegate pigmentation blues, browns, black, red, or white with poorly defined or irregular borders. Common moles, dysplastic nevi, and risk of melanoma.
A dysplastic nevus may occur anywhere on the body, but it is usually seen in areas exposed to the sun, such as on the back. The immunohistochemistry which is used for the staining includes s100, a103, and mitf. Clinically, dysplastic nevi show variation in size, shape, and coloration. The characteristics of a dysplastic nevi consists of large pigmented lesions that frequently measure from 5 15 mm in diameter, with irregular borders and colors that range from tan to dark. Dysplastic atypical, clark melanocytic nevi are acquired pigmented melanocytic proliferations of the skin with distinct clinical and histologic features. We all have many different types of moles in our body and many times dermatologists biopsy these moles that look a little bit abnormal and have a different shape or different configuration. Elder d e 2010 histopathology56, 112120 dysplastic naevi. Around one out of ten individuals have at least one unusual mole. One or more firstdegree or seconddegree relatives with malignant melanoma. Pathology of dysplastic melanocytic nevus atypical. Dysplastic nevi are described as being on a continuum between common acquired nevi and melanoma because they are morphologically and biologically intermediate between these 2 entities. A metaanalysis of casecontrol studies found that the relative risk of melanoma is 1. Media in category histopathology of dysplastic nevus the following 6 files are in this category, out of 6 total. Melanocytic proliferations are the most common tumors of the conjunctiva, accounting for up to 53% of all conjunctival neoplasms.
Nevi often irregular in shape, asymmetric, with variable coloration and borders that vary from sharply to poorly defined. If recognition of dysplastic melanocytic nevi has biologic signifi cance, then pathologists must be able to consistently distinguish dysplastic nevi from melanoma. Dysplastic nevus, abbreviated dn, is a common melanocytic lesion that is closely associated with malignant melanoma it is also known as atypical nevus, dysplastic melanocytic nevus, clark nevus, and nevus with architectural disorder in 1992, the term nevus with architectural disorder was recommended by the american national institutes of health nih. Highly acclaimed and considered the leading reference in the field, pathology of melanocytic nevi and melanoma has once again been fully revised, updated, and expanded to reflect the most recent advances and techniques in the field of melanoma pathology. The terms atypical nevi and dysplastic nevi are clinically used interchangeably, although in theory a dysplastic nevus refers to a histologic diagnosis. These are features that are also seen in melanoma, and it is a matter of degree that allows for the clinical distinction of dysplastic nevus from common nevus or melanoma. Anatomic pathology grading atypical melanocytic nevi. Dysplastic naevi are now to be graded as low grade dysplastic naevus previous moderately dysplastic naevus or high grade dysplastic naevus previous severely dysplastic naevus. Atypical moles, also known as dysplastic nevi, are unusuallooking moles that have irregular features under the microscope.
A dysplastic nevus, also called an atypical mole, is a mole that looks different than common moles in certain ways. Histopathology skincompound clarks nevus dysplastic nevus. Dysplastic naevian alternative view, histopathology 10. In 1978, clark 11 reported an increased incidence of cutaneous melanoma in families with multiple melanocytic lesions, introducing the melanoma tumor progression model from melanocytic nevi. Pdf before the controversies surrounding dysplastic melanocytic nevi are resolved, dermatopathologists must be able to reliably distinguish. Relatively rare at genital sites compared to other melanocytic lesions j cutan pathol 1987. A point mutation in the braf gene most often v600e is usually the initiating genetic mutation. Benign melanocytic naevi in various sites may show unusual histopathological features that may mimic melanoma naevi from the auricular region, breast, conjunctiva and ankle sometimes have a rather atypical proliferation of melanocytes in the epidermis, often with pagetosis and cytological atypia.
Some people have only a couple of dysplastic nevi, but other people have more than 10. Although a consensus conference in 1992 recommended that the term dysplastic. A dysplastic nevus may also appear in areas not exposed to the sun, such as the scalp, breasts, and areas below the waist 1, 3. A pragmatic approach to atypical pigmented lesions that. Department of pathology, dokuz eylul university, faculty of medicine. If provided, the size of the lesion and information as to whether or not it has been sampled in its clinical entirety may have a signi. New chapters on mucosal melanoma, ocular melanoma, and pigmented lesions of the nail apparatus have been included in this new edition. Synonyms for dn used in the literature include bk mole, atypical melanocytic hyperplasia, atypical melanocytic nevus, or atypical melanocytic proliferation 1,2,3,4,5. Since its description in the 1970s, the dysplastic nevus has been a source of confusion, and whether it represents a precursor to melanoma remains a controversial subject. Dysplastic nevus or atypical mole is a mole that is different from a common mole. The term dysplastic naevus was then proposed and remains the term in most common use. They are significant only in relation to melanoma, as simulants of melanoma, as markers of individuals at increased. My approach to atypical melanocytic lesions journal of clinical.
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