Clinical, dermoscopic and histopathological evaluation of the. Atypical lentiginous melanocytic proliferations in elderly patients continue to pose a diagnostic dilemma with lesions variably categorized as. However, no single criterium is definitive in the differential diagnosis between spitz nevus and melanoma. Recent data show that mutations in genes responsible for common nevi or melanomas such as braf, nras,orckit are rare in blue nevi. State of the art, nomenclature, and points of consensus. An atypical mole may also be referred to as an atypical melanocytic nevus, atypical nevus, bk mole, clarks nevus, dysplastic melanocytic nevus, or nevus with architectural. Lott et al 3 recently studied the clinical features of 484 spitz nevi in comparison with. The atypical spitz nevus is difficult to formally define. Dec 23, 2009 mckee p h 2010 histopathology56, 100111 clues to the diagnosis of atypical melanocytic lesions. Pdf low concordance in grading atypical dysplastic melanocytic nevi amn has been reported. In 1992, the nih recommended that the term dysplastic nevus be avoided in favor of the term atypical mole. Clinical, dermoscopic and histopathological evaluation of. 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.
Atypical genital nevus characteristically presents on the lower genital tract of premenopausal women. Jan 21, 2008 atypical melanocytic lesions are relatively common and can be difficult to diagnose with confidence. Dysplastic atypical nevus syndrome includes familial originally known as bk mole syndrome and sporadic occurrence of multiple dysplastic nevi in an individual. Mar 24, 2018 dysplastic atypical, clarks nevus clinical features. Within the last few years, sentinel lymph node biopsy slnb has been proposed as a useful tool in the management of melanocytic neoplasms of uncertain behavior, such as the atypical spitz nevus. Atypia is noncommittal and is a descriptive diagnosis that alerts the treating physician that this is a lesion that may require careful followup as well as consideration for a. Blue nevus is a benign melanocytic lesion whose most frequent variants are dendritic common blue nevus and cellular blue nevus. People with atypical nevus syndrome may have hundreds of moles of varying sizes and colors. Pdf before the controversies surrounding dysplastic melanocytic nevi are resolved, dermatopathologists must be able to reliably distinguish. Photos click on tab labeled dysplastic atypical banal common nevi evolve through a process from a junctional nevus to a compound nevus to a dermal nevus.
Although they are benign, they exhibit some of the clinical and histologic features of malignant melanoma. Atypical lentiginous nevus, originally defined as lentiginous dysplastic nevus of the elderly, was first described in 1991 by kossard et al. A dysplastic nevus or atypical mole is a nevus mole whose appearance is different from that of common moles. The term melanocytic nevus comprises a wide range of benign melanocytic proliferations that differ with respect to their epidemiology, morphology, genetics and associated melanoma risk. Trichoblastoma is the most common neoplasm developed in nevus sebaceus of jadassohn. The term atypical naevus is sometimes used to mean any funnylooking mole, and sometimes to mean a melanocytic lesion that is suspected of being a malignant melanoma a cancerous mole. The histologic correlate of the clinical atypical nevus is commonly termed a dysplastic nevus, which is believed by some to lie on the spectrum between a common or typical nevus and melanoma. Pdf atypical cellular blue nevus or malignant blue nevus. We prefer the term atypical melanocytic nevus and qualify it with the degree of atypia, usually a lowgrade or highgrade atypia. Melanocytic naevi of special sites diagnostic histopathology. An interobserver agreement study article pdf available in journal of investigative dermatology 1003. Anatomic pathology grading atypical melanocytic nevi. Dysplastic naevi were the first type to be described and have specific features. Atypical nevi, also known as clarks or dysplastic nevi, are noncancerous moles that are usually larger than ordinary moles and vary in color from pink to dark brown.
Challenging areas in diagnosis of blue nevi include recognition of amelanotic, desmoplastic, atypical, and malignant variants of blue nevus. A practical approach to the diagnosis of melanocytic lesions. Common terms, including mole, birthmark, and beauty mark, are used to describe nevi, but these terms do not distinguish specific. My approach to atypical melanocytic lesions journal of clinical. There is a recently recognized and relatively common group of melanocytic naevi that share histopathologic features in common with dysplastic naevi and malignant melanoma. Atypical cellular blue nevi cellular blue nevi with. Mckee p h 2010 histopathology56, 100111 clues to the diagnosis of atypical melanocytic lesions. One definition of an atypical naevus is a mole with at least 3 of the following features. Soeprono teaches and practices dermatopathology at loma linda university, school of medicine, department of dermatology. Atypical melanocytic lesions are relatively common and can be difficult to diagnose with confidence.
An atypical nevus may form when melanocytes, the cells responsible for skin color, form clusters instead of spreading evenly throughout the skin. Atypical cellular blue nevi cellular blue nevi with atypica. Atypical cellular blue nevus presents an intermediate histopathology between the typical and a rare variant of malignant blue nevusmelanoma arising in a cellular blue nevus. To further muddy the waters, the terms atypical nevus and dn have been used. The concordance between clinically atypical nevi and the histologic findings of dysplasia is poor. Both classic and atypical spitz nevi are uncommon melanocytic lesions usually presenting in children and adolescents.
Nevus atypical nevus dysplastic nevi are usually compound nevi with peripheral lentiginous and junctional activity and random cytological atypia in the epidermal component. Dysplastic nevi and benign nevi see online here a nevus is a condition which occurs due to the increase in the number of melanocytes. The histology of these atypical vulvar nevi can be striking at low power, often. 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. Pathology moderate atypical dysplastic nevus, recommend further excision. The terms atypical nevi and dysplastic nevi are clinically used interchangeably, although in theory a dysplastic nevus refers to a histologic diagnosis. Atypical nevi of scalp of adolescents resemble those in genitalia with apparent benign behavior j cutan pathol 2007. People with atypicalnevus syndrome may have hundreds of moles of varying sizes and colors. The nomenclature and histologic criteria for atypical nevi remains controversial though there is general agreement on the following features. Highly variable, from small, symmetric, and evenly pigmented to large 6 mm, irregularly shaped, and irregularly pigmented cutaneous marker for the dysplastic nevus syndrome, but it is of uncertain significance there is an increased risk of melanoma change gross photo of. Apr 30, 2010 there is a recently recognized and relatively common group of melanocytic naevi that share histopathologic features in common with dysplastic naevi and malignant melanoma.
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. Because atypical lentiginous nevus manifests clinically as pigmented. An atypical spitz nevus shares histologic features with the classic spitz nevus, but it may have one or more atypical features, which can be characteristic of malignancy. Conflicts of interest atypical melanocytic proliferations.
An 8yearold child presented a pigmented lesion in the buttock since birth, but with. Atypical moles are benign melanocytic nevi with irregular and illdefined borders, variegated colors usually of brown and tan tones, and macular or papular components. Pathology moderate atypical dysplastic nevus, recommend. In contrast, the atypical spitz nevus has an unknown clinical prognosis, and its clinical and histologic traits are loosely defined. The pigmented lentiginous naevus with atypia was first described in 1991 but has only recently been more commonly recognized.
Atypical nevi, also known as clarks or dysplastic nevi, are noncancerous moles that are usually larger than ordinary moles. Sporadic or part of dysplastic nevus syndrome phenotypic marker of patients at increased risk of melanoma individual nevi rarely progress to melanoma histopathology 2010. The original designation of dysplastic nevus has been replaced with the term atypical nevus, and the pathologic description should use the term nevus with architectural disorder and indicate the extent of cytologic atypia. The atypical melanocytic nevus aka the dysplastic nevus. Patients with atypical moles have an increased risk of melanoma. Soepronos textbook is available on and includes detailed information on over 600 entities and includes four dvd diskettes with highresolution images that provide a virtual dermatopathology reference and guide.
The cardinal features are a cytomorphology defining that encountered in the spitzdefining that encountered in the spitz ss nevus in nevus in concert with an architecture typical for a dysplastic nevus. Threshold for reexcision of histologically transected. It is also known as atypical nevus, dysplastic melanocytic nevus, clark nevus, and nevus with architectural disorder. Dysplastic atypical, clarks nevus clinical features. Jun 24, 2005 atypical lentiginous melanocytic proliferations in elderly patients continue to pose a diagnostic dilemma with lesions variably categorized as dysplastic nevus, atypical junctional nevus, melanoma. Nevi often irregular in shape, asymmetric, with variable coloration and borders that vary from sharply to poorly defined. They were first recognized clinically as large atypical moles seen in members of two melanoma. Histopathological diagnosis of small melanocytic lesions suspicious. Spitzoid melanocytic lesions may be broadly categorized into spitz nevi, asts, and spitzoid melanomas. Dysplastic naevi are benign melanocytic naevi that are defined both histologically and clinically. The borders may be incompletely excused, or te pathologist may feel that a wide enough clear margin has not been achieved.
Selfcare guidelines protective measures, such as avoiding skin exposure to sunlight during peak sun hours 10 am to 3 pm, wearing protective clothing, and applying highspf sunscreen, are essential for reducing exposure to harmful ultraviolet uv light. The occurrence of the melanocytes can be both congenital, as well as acquired, and the melanin pigmentation can also be hypo or hyperpigmentation. Dysplastic nevi are relatively common in the general population. Jul 31, 20 dermatopathology reference describes nevus spilus congenital speckled lentiginous nevus histopathology including histologic features and provides links to additional medical references. The classic spitz nevus typically is benign and has characteristic clinical and histologic features. 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 are essentially the same criteria that are used to distinguish a banal nevus from melanoma. About 1 out of every 10 americans has at least one atypical mole. Architectural disorder with asymmetry intraepidermal melanocytes extend beyond the main dermal component subepidermal fibroplasia lentiginous melanocytic hyperplasia with spindled or epithelioid melanocytes nevus cell nests are of. 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. These naevi have been termed naevi of special sites or naevi with siterelated atypia as distinctive features have been correlated with specific anatomic sites. Nevus or nevi if multiple is a nonspecific medical term for a visible, circumscribed, chronic lesion of the skin or mucosa. Atypical junctional nevi n21, atypical compound nevi n17, and atypical lentiginous melanocytic hyperplasia with architectural features of atypical nevus n7. A subset of melanocytic nevi share features with melanoma and nevi with. Dysplastic nevus, abbreviated dn, is a common melanocytic lesion that is closely associated with malignant melanoma.
If recognition of dysplastic melanocytic nevi has biologic signifi cance, then pathologists must be able to consistently distinguish dysplastic nevi from melanoma. A clinical and histopathologic study of 14 cases atypical lentiginous nevus of the elderly is a peculiar form of dysplastic nevus. Dec 07, 20 atypical melanocytes were present in 18 cases 56%. Junctional nevi are the result of a single abnormal melanocyte that begins to proliferate at the dermal epidermal junction, and are often seen clinically as a dark flat nevus. Atypical moles can be distinguished visually by clinical features of size greater than 6 mm in diameter, color variegation, indistinct borders, and textured surface. Melanocytic pathology is one of the most difficult areas in surgical pathology. State of the art, nomenclature, and points of consensus and. Division of pathology and laboratory medicine, medical school. Detailed knowledge of the classical form of spitz nevi is essential for the differential diagnosis with melanoma. Atypical melanocytic lesions diagnostic histopathology. As in many such studies, the histology of these nevi was not examined. Objective to achieve a clinicopathologic classification of spitz nevi by comparing their clinical, dermoscopic, and histopathologic features. Jun 01, 2015 atypical moles are benign pigmented lesions.
Histopathologic recognition and grading of dysplastic. Clues to the diagnosis of atypical melanocytic lesions. Pdf histopathologic recognition and grading of dysplastic. It may be abbreviated aln it can be considered a type of dysplastic nevus. Atypical lentiginous nevus, also atypical lentiginous nevus of the elderly, is a melanocytic lesion associated with old age and melanoma. Management is by close clinical monitoring and biopsy of highly atypical or changed lesions. The more of these moles you have, the greater your risk of developing melanoma the deadliest type of skin cancer. In situ malignant change is described in a significant proportion of cases. Pdf critical analysis of histologic criteria for grading atypical.
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