What are junctional melanocytes?
Table of Contents
Junctional Nevi are clusters of melanocytes that develop within the superficial layer of skin, the epidermis. They appear as slightly elevated papules or macules, usually with a diameter <6mm. Junctional nevi are typically circular with regular borders and their coloring varies from tan to brown to black.
Does melanocytic mean melanoma?
Background Moles, or melanocytic nevi, are both markers of an increased risk of cutaneous melanoma and direct precursor lesions.
What is a junctional melanocytic proliferation?
The histological term, junctional melanocytic hyperplasia (JMH), refers to the proliferation of single melanocytes along the dermal epidermal junction that is the basal layer where normal melanocytes reside. JMH is characteristic of lentigo simplex, junctional nevus, and dysplastic nevus.
What are Monomorphous melanocytes?
Cytologically, the monomorphous melanocytes of melanocytic nevi are in an erratic, unpredictable assortment of small and minimally larger sizes and shapes, e.g., round, oval, spindle-shaped, polygonal, plasmacytoid, ballooned, fusiform, dendritic, pagetoid and multinucleate.
What are melanocytes?
(meh-LAN-oh-site) A cell in the skin and eyes that produces and contains the pigment called melanin. Enlarge. Anatomy of the skin, showing the epidermis, dermis, and subcutaneous tissue. Melanocytes are in the layer of basal cells at the deepest part of the epidermis.
What are atypical melanocytes?
Atypical melanocytic lesions are pigmented moles that have abnormal cells under a microscope. These lesions will need to be evaluated by excision (removal) and evaluation by a dermatopathologist in a laboratory setting.
Are melanocytes precancerous?
Compared with other clinically apparent, benign, but potentially precancerous lesions, melanocytic nevi are unique as they arise relatively early in life.
Where are the melanocytes?
A cell in the skin and eyes that produces and contains the pigment called melanin. Anatomy of the skin, showing the epidermis, dermis, and subcutaneous tissue. Melanocytes are in the layer of basal cells at the deepest part of the epidermis.
How do you identify melanocytes?
Melanocytes appeared as bright round, oval, fusiform, or dendritic cells. The architectural growth pattern of melanocytes could be analyzed. Melanocytes were identified by their nested growth pattern as aggregates of bright round to oval structures at the dermoepidermal junction or in the superficial dermis.
What is junctional melanocytic nevus with mild atypia?
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. A junctional nevus will typically evolve over time into a compound nevus, which is a nevus with both epidermal and dermal melanocytes.
What is mild melanocytic atypia?
Mild cytologic atypia is defined as lesions with ovoid- to ellipsoid-shaped nuclei, that are smaller than basal keratinocytes, with hyperchromatic nuclei, and without a visible or small nucleoli, typically restricted to the shoulder region.
Is junctional nevus precancerous?
Junctional naevi occur at any site on the body and are regularly shaped, usually round or oval. They are most often uniform in colour and range in pigmentation from light to dark brown. They are usually <7 mm in diameter. They are benign lesions but have the potential to undergo transformation to malignant melanoma.
What is junctional melanocytic nevi?
Junctional Melanocytic Nevus — Ozark Dermatology Junctional Nevi are a sub-class of Common Acquired Melanocytic Nevi Typically they are light to dark brown macules, 1-10 mm in diameter, and located on sun exposed areas such as the trunk. Junctional Nevi are benign proliferations of melanocytes in the epidermis.
What is junctional melanocytic hyperplasia?
Junctional Melanocytic Hyperplasia The term “junctional melanocytic hyperplasia” (JMH) refers to the proliferation of melanocytes along the dermo–epidermal junction that is the basal layer where normal melanocytes reside.
What is the appearance of compound melanocytic naevi pathology?
The epidermis may be normal in appearance, acanthotic or display seborrhoeic keratosis -like changes. Nests of melanocytes are found at the dermoepidermal junction and within the dermis. Melanocytes exhibit maturation as they become deeper and tend to be smaller with less pigmentation. (figures 2, 3). Compound melanocytic naevi pathology
How to characterize melanocytic nevus cells?
The quantitative analysis was based on TPEF, SHG, and melanocyte parameters derived from 3D in vivoimage analysis. Common melanocytic nevi were characterized in MPM images by normal morphology of keratinocytes of the epidermal layers, well-defined nests of nevus cells surrounded by collagen fibers at the EDJ and dermis, and elongated rete ridges.