[Figure - 1],[Figure - 2]

Diagnosis: Hyperkeratotic type of seborrheic keratoses

Histopathological findings

There was pronounced hyperkeratosis and papillomatosis with little acanthosis. The numerous digitate upward extensions of epidermis lined papillae resembling church spires were present. The epidermis was comprised largely of squamous cells interspersed with aggregates of basaloid cells.

Discussion

Histopathological finding of viral (HPV) wart are acanthosis, papillomatosis, hyperkeratosis, and foci of vacuolated cells referred to as koilocytes found in the upper stratum malpighii and in the granular layer. Mitotic figures may be present. While in this case there was presence of squamous and basaloid cells and absence of koilocytes helped in diagnosis of seborrheic keratoses (SK).

Seborrheic keratoses also known as seborrheic wart, senile wart, brown wart or basal cell papilloma, is a benign tumor, frequently pigmented, more common in the elderly and composed of epidermal keratinocytes. The etiology of SK is not known. Epidermal growth factor or their receptors have been implicated in the development of SK. Reticulated SK are usually found on sun exposed skin and it may develop from solar lentigines. A familial trait exists for the development of multiple SK in about half of the patients, with an autosomal dominant mode of inheritance.

Seborrheic keratoses usually begin with the appearance of one or more sharply defined, light brown, flat macules. The lesions may be sparse or numerous. As they initially grow, they develop a velvety to finely verrucous surface, followed by an uneven warty surface with multiple plugged follicles and a dull or lacklustre appearance. They typically have an appearance of being stuck on the skin surface. Seborrheic keratoses can occur on almost any site of the body, with the exception of the palms and soles, and mucous membranes. ^[1]

Differential diagnosis

The clinical differential diagnosis of SK includes malignant melanoma, melanocytic nevus, verruca vulgaris, condyloma acuminatum, fibroepithelial polyp, epidermal nevus, actinic keratoses, pigmented basal cell carcinomas, and squamous cell carcinomas.

Epiluminescent surface microscopic examination of SK reveals globulelike structures. ^[2] The globule-like structures in SK are due to intraepidermal horn cysts filled with cornified cells containing melanin. They resemble the brown globules observed in melanocytic neoplasms, which are due to nests of melanocytes at the dermoepidermal junction.

Medical treatment

Ammonium lactate and alpha hydroxy acids have been reported to reduce the thickness of SK. Superficial lesions can be treated by carefully applying pure trichloroacetic acid and repeating if the full thickness is not removed on the first treatment.

Surgical treatment

A variety of techniques may be employed to treat SK. They include cryotherapy with carbon dioxide (dry ice) or liquid nitrogen, electrodesiccation, electrodesiccation and curettage, curettage alone; shave biopsy or excision using a scalpel or laser, or dermabrasion surgery. Some of these techniques destroy the lesion without providing a specimen for histopathologic diagnosis.

Even though Seborrheic keratoses can occur on any body site, ^[3] our patient seems to have an interesting presentation. Strict confinement of these lesions to skin on the genitalia and sparing of classical sites is unusual. To the best of our information, seborrhoeic keratosis is not reported exclusively on and around the genitalia. Moreover, seborrhoeic keratosis in this location resembles verruca plana ^[4] more closely than at any other site and a high index of suspicion is essential for correct diagnosis.

We need to differentiate SK from viral (HPV) wart because if patient has viral (HPV) wart than we need to follow the patient with regular  Pap smear ^{More Details} examination as screening measure for vaginal intraepithelial neoplasia (VIN) and cervical intraepithelial neoplasia (CIN).

Patient was treated with liquid nitrogen cryotherapy.