Verruciform xanthoma is uncommon, with a female:male ratio of 1:1.1

Nevi are typically diagnosed clinically with the naked eye or using dermatoscopy. More advanced imaging tests are available for distinguishing melanocytic nevi from melanoma, including computerized dermoscopy and image analysis. The management of nevi depends on the type of nevus and the degree of diagnostic uncertainty. Some nevi are known to be benign, and may simply be monitored over time. Others may warrant more thorough examination and biopsy for histopathological examination (looking at a sample of skin under a microscope to detect unique cellular features). For example, a clinician may want to determine whether a pigmented nevus is a type of melanocytic nevus, dysplastic nevus, or melanoma as some of these skin lesions pose a risk for malignancy. The ABCDE criteria (asymmetry, border irregularity, color variegation, diameter > 6 mm, and evolution) are often used to distinguish nevi from melanomas in adults, while modified criteria (amelanosis, bleeding or bumps, uniform color, small diameter or de novo, and evolution) can be used when evaluating suspicious lesions in children. In addition to histopathological examination, some lesions may also warrant additional tests to aid in diagnosis, including special stains, immunohistochemistry, and electron microscopy. Typically; the nevi which exist since childhood are harmless

The management of a nevus depends on the specific diagnosis, however, the options for treatment generally include the following modalities:

Differential diagnosis includes seborrheic keratosis, verruca simplex, condyloma acuminatum, granular cell myoblastoma, vulvar intraepithelial neoplasia, bowenoid papulosis, erythroplasia of Queyrat, and verrucous carcinoma

Tissue biopsy is usually indicated to rule out other causes of white patches and also to enable a detailed histologic examination to grade the presence of any epithelial dysplasia. This is an indicator of malignant potential and usually determines the management and recall interval. The sites of a leukoplakia lesion that are preferentially biopsied are the areas that show induration (hardening) and erythroplasia (redness), and erosive or ulcerated areas. These areas are more likely to show any dysplasia than homogenous white areas.

Brush biopsy/exfoliative cytology is an alternative to incisional biopsy, where a stiff brush is scraped against the lining of the mouth to remove a sample of cells. This is then made into a smear which can be examined microscopically. Sometimes the biopsy site can be selected with adjunct methods which aim to highlight areas of dysplasia. Toluidine blue staining, where the dye is preferentially retained by dysplastic tissue, is sometimes used, but there is high false positive rate. Other methods involve the use of illuminescence, relying on either the property of normal autoflorescent molecules in mucosa such as collagen and keratin which is lost from areas of dysplasia or carcinoma under blue light, or by initially staining of the mucosa with toluidine blue or dilute acetic acid and examination under white light.

Epithelioma cuniculatum (also known as Carcinoma cuniculatum, and Ackerman tumor) is a skin lesion, a type of verrucous carcinoma that may occur on the sole of the foot.

Giant condyloma acuminatum (also known as a Buschke–Löwenstein tumor and "Giant condyloma of Buschke–Löwenstein tumor") is a rare cutaneous condition characterized by an aggressive, wart-like growth that is a verrucous carcinoma. It is attributed to human papillomavirus.

Oral florid papillomatosis is a condition characterized by a white mass resembling a cauliflower covering the tongue and extending onto other portions of the mucous membranes. This is a type of verrucous carcinoma.

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 seborrheic keratoses on facial skin can be very difficult to differentiate from lentigo maligna even with dermatoscopy. Clinically, epidermal nevi are similar to seborrheic keratoses in appearance. Epidermal nevi are usually present at or near birth. Condylomas and warts can clinically resemble seborrheic keratoses, and dermatoscopy can be helpful. On the penis and genital skin, condylomas and seborrheic keratoses can be difficult to differentiate, even on biopsy.

To date, the gold standard in the diagnosis of seborrheic keratosis is represented by the histolopathologic analysis of a skin biopsy.

Leukoplakia has a wide range of possible histologic appearances. The degree of hyperkeratosis, epithelial thickness (acanthosis/), dysplasia and inflammatory cell infiltration in the underlying lamina propria are variable. In mucous membranes, hyperkeratosis can be defined as "an increase in the thickness of the keratin layer of the epithelium, or the presence of such a layer in a site where none would normally be expected." In leukoplakia, the hyperkeratosis varies in thickness, and may be either ortho- or para-keratosis, (depending upon whether cell nuclei are lost or retained in the superficial layers respectively), or a mixture of both in different areas of the lesion.

The epithelium may show hypertrophy (e.g. acanthosis) or atrophy. Red areas within leukoplakia represent atrophic or immature epithelium which has lost the ability to keratinize. The transition between the lesion and normal surrounding mucosa may be well demarcated, or poorly defined. Melanin, a pigment naturally produced in oral mucosa, can leak from cells and give a grey color to some leukoplakia lesions.

Hyperkeratosis and altered epithelial thickness may be the only histologic features of a leukoplakia lesion, but some show dysplasia. The word "dysplasia" generally means "abnormal growth", and specifically in the context of oral red or white lesions refers to microscopic changes ("cellular atypia") in the mucosa that indicate a risk of malignant transformation. When dysplasia is present, there is generally an inflammatory cell infiltration in the lamina propria. The following are commonly cited as being possible features of epithelial dysplasia in leukoplakia specimens:

- Cellular pleomorphism, in which cells are of abnormal and different shapes.

- Nuclear atypia, in which the nuclei of cells varies in size, any may be increased in size relative to the cytoplasm, shape, and may stain more intensely. There may also be more prominent nucleoli.

- Increased number of cells seen undergoing mitosis, including both normal and abnormal mitoses. Abnormal mitosis may be abnormally located, e.g. occurring in suprabasal cells (cell layers more superficial to the basal cell layer) or of abnormal form, e.g. "tri-radiate mitoses" (a cell splitting into 3 daughter cells rather than only 2)

- Loss the normal organization of the epithelial layers. The distinction between the epithelial layers may be lost. Normally stratified squamous epithelium shows progressive changes in the form of cells from the basal to the superficial layers, with cells becoming more flat ("squames") towards the surface as a continuous maturation process. In dysplastic epithelium, cells may become vertically orientated rather than becoming flat towards the surface.

- There may be abnormal keratinization, where keratin is formed below the normal keratin layer. This can occur in individual cells or groups of cells, forming an intraepithelial keratin pearl. There may be an increase in number of basal cells, and they may lose their cellular orientation (losing their polarity and long axis).

- Alteration of the normal epithelial-connective tissue architecture - the rete pegs may become "drop shaped". wider at their base than more superficially.

Generally dysplasia is subjectively graded by pathologists into mild, moderate or severe dysplasia. This requires experience as it is a difficult skill to learn. It has been shown that there is high degree of inter-observer variation and poor reproducibility in how dysplasia is graded. Severe dysplasia is synonymous with the term carcinoma in situ, denoting the presence of neoplastic cells which have not yet penetrated the basement membrane and invaded other tissues.

This form of cancer is often seen in those who chew tobacco or use snuff orally, so much so that it is sometimes referred to as "Snuff dipper's cancer." Chewing betel nuts is an additional risk factor commonly seen in Taiwan.

Surgical excision or laser therapy are possible treatments. Surgical excision alone was effective for controlling VC, but elective neck dissection was not necessary even in patients in the advanced stages.

Bowenoid papulosis is a cutaneous condition characterized by the presence of pigmented verrucous papules on the body of the penis. They are associated with human papillomavirus, the causative agent of genital warts. The lesions have a typical dysplastic histology and are generally considered benign, although a small percentage will develop malignant characteristics.

It is considered as a pre-malignant condition. Other terms used to describe the condition are: Erythroplasia of Queyrat, Squamous cell carcinoma in situ and Bowen’s disease. The term "Bowenoid papulosis" was coined in 1977 by Kopf and Bart and is named after dermatologist John Templeton Bowen.

The term “intraepithelial neoplasia” defines a premalignant intraepithelial change.

On the vulva it is termed VIN (vulvar or vulval intraepithelial neoplasia); on the penis, PIN (penile intraepithelial neoplasia); and on or around the anus, AIN (anal intraepithelial neoplasia). The terminology has been very confusing and it is now recommended that the terms Bowen’s disease, erythroplasia of Queyrat, and bowenoid papulosis should not be used for lesions in the anogenital area. However, dermatologists still recognize a distinct clinical variant, bowenoid papulosis, characterized by discrete papules in a younger age group and a tendency for spontaneous regression. Additionally, some authorities believe that erythroplasia of Queyrat and Bowen’s disease remain useful terms in men.

Papillomatosis cutis carcinoides (also known as "Gottron's carcinoid papillomatosis" and "Papillomatosis cutis carcinoides of Gottron–Eisenlohr") is a cutaneous condition characterized by verrucous skin lesions, and is due to an HPV infection of the skin.

Due to the rarity of different types of vascular conditions, angiokeratomas may be misdiagnosed. A biopsy of the lesion can produce a more accurate diagnosis.

Other cancerous lesions in the differential diagnosis include Paget's disease of the vulva and vulvar intraepithelial neoplasia (VIN). Non-cancerous vulvar diseases include lichen sclerosus, squamous cell hyperplasia, and vulvar vestibulitis. A number of diseases cause infectious lesions including herpes genitalis, human papillomavirus, syphilis, chancroid, granuloma inguinale, and lymphogranuloma venereum.

No treatment of seborrheic keratoses is necessary, except for aesthetic reasons. Since a slightly increased risk of localized infection caused by picking at the lesion has been described, if a lesion becomes itchy or irritated by clothing or jewelry, a surgical excision is generally recommended.

Small lesions can be treated with light electrocautery. Larger lesions can be treated with electrodesiccation and curettage, shave excision, or cryosurgery. When correctly performed, removal of seborrheic keratoses will not cause much visible scarring except in persons with dark skin tones.

Vesicovaginal fistulae are typically repaired either transvaginally or laparoscopically, although patients who have had multiple transvaginal procedures sometimes attempt a final repair through a large abdominal incision, or laparotomy.

The laparoscopic (minimally invasive) approach to VVF repair has become more prevalent due to its greater visualization, higher success rate, and lower rate of complications.

Acrokeratosis verruciformis (also known as "Acrokeratosis verruciformis of Hopf" is a rare autosomal dominant disorder appearing at birth or in early childhood, characterized by skin lesions that are small, verrucous, flat papules resembling warts along with palmoplantar punctate keratoses and pits. However sporadic forms, whose less than 10 cases have been reported, presents at a later age, usually after the first decade and generally lack palmoplantar keratoses.

Whether acrokeratosis verruciformis and Darier disease are related or distinct entities has been controversial, like Darier's disease, it is associated with defects in the ATP2A2 gene. however the specific mutations found in the ATP2A2 gene in acrokeratosis verruciformis have never been found in Darier's disease.

Morbidity and mortality range from both extremes as the significance correlate with the underlying systemic disease.

Overall, five-year survival rates for vulvar cancer are around 78% but may be affected by individual factors including cancer stage, cancer type, patient age and general medical health. Five-year survival is greater than 90% for patients with stage I lesions but decreases to 20% when pelvic lymph nodes are involved. Lymph node involvement is the most important predictor of prognosis. Thus, early diagnosis is important.

Porokeratosis is a specific disorder of keratinization that is characterized histologically by the presence of a cornoid lamella, a thin column of closely stacked, parakeratotic cells extending through the stratum corneum with a thin or absent granular layer.

There seems to be beneficial responses to clindamycin therapy as the lesions regress. This leads to the hypothesis that microorganisms may be playing a role in the initial stages of Kyrle disease.

A family with Kyrle disease were examined which their skin lesions were benign. However, when three of the young adult members were closely examined, they had posterior subcapsular cataracts and two of those three developed multiple tiny yellow-brown anterior stromal corneal opacities. In order to determine if there is any correlation between Kyrle disease and the ocular observations, more cases of Kyrle disease are to be analyzed.

All in all, since Kyrle disease is relatively rare, more cases need to be studied and analyzed in order to understand the underlying pathogenesis and to improve the management of the disease.

Reported treatments include topical agents, dermabrasion, cryotherapy, laser therapy, and surgical excision. These therapies have a high failure rate because of incomplete relief of symptoms, scarring, or recurrence .

Though similar in appearance, ILVEN will not respond to therapies known to affect psoriasis. ILVEN can be very difficult to live with but can be treated. The most effective method is full-thickness excision of the lesion. CO2 Laser Surgery can resurface the skin to give a flat, smoother and more normal appearance, but does not remove the lesion.

Outpatient treatments such as interventional radiology, lasers, and physical therapy are employed to reduce the severity of the vascular lesions. However, in some cases lasers have caused a reaction in the tissue causing it to expand and become exposed to infection. Excision and grafting may be necessary to remove the lesion. Recovery time on such an operation ranges from 3 to 12 weeks depending on location of the graft, healing time and the possibility of complications.