What Is Verrucous Carcinoma?

Verrucous carcinoma is a rare, slow-growing type of cancer. It is a low-grade form of squamous cell carcinoma, the cancer that starts in the flat cells lining the skin, mouth and other moist surfaces. It gets its name from its warty ("verrucous") look, and it is often mistaken for a wart or another harmless growth at first.

The good news is that it rarely spreads to other parts of the body, and surgery cures most people. The main danger is that, left alone, it keeps growing into nearby tissue, including muscle and bone.

Key facts

• What it is: a low-grade, well-differentiated variant of squamous cell carcinoma.
• Where it appears: most often in the mouth; also on the genitals or around the anus, on the sole of the foot, and in the voice box (larynx).
• Main risks: tobacco, especially chewing tobacco and snuff; long-standing irritation; possibly human papillomavirus (HPV).
• Spread: grows slowly and locally; spread to lymph nodes or distant organs is rare.
• Treatment: surgical removal with a margin of healthy tissue is the usual first choice.
• Outlook: very good when it is fully removed, though it can come back.

Other names

Because it was described separately in different parts of the body, verrucous carcinoma goes by several names:

Doctors now generally treat these as one condition appearing in different places.

Where it develops

• Mouth: the most common site, usually the inside of the cheek, gums or jaw ridge. Read more about oral verrucous carcinoma.
• Genital and anal area: a large, cauliflower-like growth that can look like genital warts.
• Foot: most often the ball of the foot, then the toes and heel. It may be treated as a stubborn verruca for a long time before it is diagnosed.
• Larynx and other sites: less common, but possible.

See verrucous carcinoma in different parts of the body for more detail.

Causes and risk factors

The exact cause isn't fully understood, but the main known risk factors are:

• Tobacco: smokeless tobacco (snuff, chewing tobacco, betel quid) is strongly linked to oral verrucous carcinoma, and smoking also raises the risk.
• HPV: some types of the wart virus have been found in these tumours, especially genital ones, but how much HPV causes verrucous carcinoma is still debated. See verrucous carcinoma and HPV.
• Long-term irritation: chronic inflammation, old scars and long-standing ulcers.
• Precancerous patches in the mouth: verrucous hyperplasia and proliferative verrucous leukoplakia can develop into verrucous carcinoma. See verrucous hyperplasia.

It mainly affects people over 50 and is more common in men.

Symptoms

Verrucous carcinoma usually starts as a painless lump or patch that grows slowly over months or years. Signs depend on where it is:

• Mouth: a thick, white or grey, warty or cauliflower-like patch. Later there may be discomfort, difficulty chewing or swallowing, and bad breath. Pain often means it has started to grow into deeper tissue.
• Genitals or anus: a growing warty mass, sometimes with itching, discharge, bleeding or pain.
• Foot: a thickened, warty lump that keeps coming back after verruca treatment. It may ooze foul-smelling material and become painful to walk on.
• Larynx: a hoarse voice that doesn't go away.

See a doctor or dentist about any wart-like growth or mouth patch that doesn't heal within 3 weeks, keeps coming back after treatment, or is getting bigger.

Is it a wart or verrucous carcinoma?

The two can look almost the same, which is why verrucous carcinoma is often diagnosed late. Warning signs that a "wart" may be something else include a growth that is unusually large, keeps returning despite treatment, bleeds or ulcerates, or slowly gets deeper. Read verrucous carcinoma vs warts.

How it's diagnosed

Diagnosis needs a biopsy: a sample of tissue examined under a microscope. Because the cells look so bland, a small or shallow sample can be mistaken for a wart or simple overgrowth, so doctors often need a large, deep biopsy, and sometimes more than one. Scans such as CT or MRI may be used to see how deep it goes, especially in the mouth or foot. See the guide to diagnosis.

Treatment

• Surgery is the main treatment: removing the tumour with a margin of healthy tissue. In the mouth this sometimes means removing part of the jawbone, followed by reconstruction. Mohs surgery may be used for some skin tumours.
• Radiotherapy is mainly used when surgery isn't possible or after surgery when the margins aren't clear. Its role is debated: older reports suggested radiotherapy could turn the tumour into a more aggressive cancer, so many specialists avoid it. Later studies found this transformation rare or absent, though the tumour responds less well to radiotherapy than to surgery.
• Other options for people who can't have surgery include drugs such as methotrexate, and for very superficial skin lesions, laser treatment, cryotherapy or photodynamic therapy. Evidence for these comes from small studies.

Home remedies don't treat verrucous carcinoma and can delay effective treatment. See treatment options.

Outlook

The outlook is very good compared with most cancers. Most people are cured by surgery, and spread to lymph nodes or distant organs is rare. Cleveland Clinic gives a five-year survival rate of more than 75%; large studies of oral verrucous carcinoma treated with surgery report higher figures.

The main problems are:

• Local damage if it grows for a long time before treatment, for example into the jaw or the bones of the foot.
• Recurrence, particularly if not all of the tumour was removed.
• New tumours in the mouth in people with other precancerous patches, so regular check-ups matter.

Read more: Is verrucous carcinoma life-threatening? and Can verrucous carcinoma spread?

Can it be prevented?

You can lower the risk by not using tobacco in any form, getting long-lasting or unusual warts checked, and seeing a dentist regularly so mouth changes are spotted early. Learn more about preventing verrucous carcinoma.

This page is for general information and isn't a substitute for advice from a doctor or dentist.