Verrucous Carcinoma

Key Points
Rare type of invasive squamous cell carcinoma
Caused by infection with Human Papilloma Virus (HPV)
Consists of a warty, discolored growth, usually appearing on the sole of the foot

Carcinoma cuniculatum, also known as verrucous carcinoma, is a specific type of squamous cell carcinoma. It appears as a single warty, discolored growth in the affected area, most commonly the sole of the foot, though it can appear anywhere on the body, including on the genitals or in the mouth. Carcinoma cuniculatum have a low risk of metastasis, but can be aggressive locally. Lesions often cause pain, can experience a odorous discharge, and cause difficulty in walking because of their location.

Carcinoma cuniculatum is generally thought to be caused by infection by Human Papilloma Virus (HPV), a virus which has many subtypes, and is the attributed cause to various other conditions, including genital warts, cervical and other types of cancer. Other causal factors are thought to include exposure to carcinogens from smoking in the case of oral lesions, or chronic inflammation. It is most commonly seen in white males.

Differential Diagnosis (Other conditions with similar appearance)
Keratoacanthoma or other types of squamous cell carcinooma
Warts, genital
Warts, nongenital ( eg palmar or plantar)
Verruca vulgaris

Diagnosis
Key Points
Diagnosis based on skin appearance
Skin biopsy performed to confirm diagnosis

Carcinoma cuniculatum is generally diagnosed based on appearance of the lesion, but a biopsy will be performed to confirm diagnosis and to rule out any other similar appearing conditions. Other testing may be performed to discover the extent of the lesion.

Treatment
Surgical excision is the primary treatment
Goal of treatment is to control/cure malignancy
Persons treated face risk of recurrence

Carcinoma cuniculatum is treated by removing the malignancy in its entirety. The usual method for this removal is excision of the lesion, sometimes through Mohs microsurgery. Other treatments commonly used include cryosurgery, curettage and electrodessication, and radiation therapies. Other treatments commonly used in squamous cell carcinoma are of relative benefit and not used as often.