Micrograph of a<unk>  (H&E stain, scanning magnification) Visual diagnosis is made by the "stuck on" appearance, horny pearls or cysts embedded in the structure. Darkly pigmented lesions can be challenging to distinguish from nodular melanomas. Furthermore, thin<unk>  on facial<unk> in can be very difficult to differentiate from lentigo maligna even with dermatoscopy. Clinically, epidermal nevi are similar to<unk>  in appearance. Epidermal nevi are usually present at or near birth. Condylomas and warts can clinically resemble<unk> , and dermatoscopy can be helpful. On the penis and genital<unk> in, condylomas and<unk>  can be difficult to differentiate, even on biopsy. A study examining over 4000 biopsied<unk> in lesions identified as<unk>  showed 3.1% were malignancies. Two-thirds of those were squamous cell carcinoma. To date, the gold standard in the diagnosis of<unk>  is represented by the histolopathologic analysis of a<unk> in biopsy. Subtypes<unk>  may be divided into the following types: Subtype (and alternative names) Characteristics Image Common<unk>  (basal cell papilloma, solid<unk>  Dull or lackluster surface. Reticulated<unk>  (adenoid<unk>  Dull or lackluster surface, and with keratin cysts seen histologically. Stucco keratosis (deratosis alba, digitate<unk> , hyperkeratotic<unk> , serrated<unk> , verrucous<unk>  Common. Dull or lackluster surface, and with church-spire-like projections of epidermal cells around collagen seen histologically. Stucco keratoses are often light brown to off-white, and are no larger than a few millimeters in diameter. They are often found on the distal tibia, ankle, and foot. Clonal<unk>  Dull or lackluster surface, and with round, loosely packed nests of cells seen histologically. Irritated<unk>  (inflamed<unk> , basosquamous cell acanthoma) dull or lackluster surface.<unk>  with squamous atypia Dull or lackluster surface, and with round, loosely packed nests of cells seen histologically. Melanoacanthoma (pigmented<unk>  Dull or lackluster surface. It involves a proliferation of keratinocytes and melanocytes. Inverted follicular keratosis Asymptomatic, firm, white–tan to pink papules Microscopically it is characterized as a well-circumscribed inverted acanthotic squamous proliferation containing squamous eddies and without significant atypia. 180px Main differential diagnoses Dermatosis papulosa nigra (DPN) is a condition of many small, benign<unk> in lesions on the face, a condition generally presenting on dark-skinned individuals. DPN is extremely common, affecting up to 30% of Black people in the US.
Seborrheic keratosis
Basal-cell carcinoma
Hydrocarbon keratosis
Melanoma
Arsenical keratosis
Wart
Actinic keratosis
Reactional keratosis