Squamous Papilloma: Understanding Your Pathology Report

by Jason Wasserman MD PhD FRCPC
July 24, 2026

A squamous papilloma is a common benign (non-cancerous) growth made up of squamous cells, the flat cells that line many surfaces of the body. The cells grow outward in small finger-like projections, which gives the growth its characteristic bumpy or wart-like shape. The medical word for this shape is papillary.

Squamous papillomas can develop anywhere squamous cells are found, including the mouth, tongue, throat, tonsils, voice box (larynx), esophagus, skin, and eyelids. They are among the most common benign growths in the mouth. This article focuses on squamous papilloma of the oral cavity (the mouth), though the same information applies at most other sites.

The most important thing to know is that a squamous papilloma is not cancer, it is not precancerous, and it does not turn into cancer.

This article explains the findings you are likely to see on a pathology report for a squamous papilloma, what each one means, and why it matters for your care.

What causes a squamous papilloma?

Most squamous papillomas are caused by infection of the squamous cells with the human papillomavirus (HPV). HPV is a very common virus, and the types that cause squamous papillomas are usually low-risk types, meaning they are not the high-risk types linked to cancer. When these low-risk types infect the squamous cells, they cause the cells to grow outward into the papillary shape that forms the growth.

Not every squamous papilloma is caused by HPV. Some develop at a site of repeated irritation or minor injury. Squamous papillomas in the esophagus, the tube connecting the mouth to the stomach, can be related to long-standing acid reflux and may be seen in people with reflux esophagitis.

What are the symptoms of a squamous papilloma?

A squamous papilloma in the mouth is usually painless and is often noticed by the patient or found by a dentist during a routine examination. Common features include:

A small, soft growth with a bumpy, wart-like, or cauliflower-like surface
A color that may be white, pink, or the same shade as the surrounding lining
A growth that is usually attached to the lining by a narrow stalk
Most often found on the tongue, the roof of the mouth (palate), or the inner lip, though it can occur anywhere in the mouth

Most squamous papillomas are small, often less than a centimeter, and grow slowly. A papilloma is usually painless unless it is repeatedly bitten or irritated. Any new or persistent growth in the mouth should be examined by a dentist or doctor.

How is the diagnosis made?

The diagnosis is made when a pathologist examines the removed growth under the microscope. A squamous papilloma is usually removed completely in a minor procedure called an excision, in which the growth is cut away under local anesthetic and sent to the laboratory. Sometimes only part of it is taken first as a biopsy. Removal usually serves two purposes at once: it provides tissue for the pathologist to examine, and it cures the papilloma.

Under the microscope, the pathologist sees squamous cells growing in the finger-like papillary pattern, each projection supported by a thin core of connective tissue. In papillomas caused by HPV, the cells may show changes typical of the virus. The pathologist also confirms that the cells are benign, with no dysplasia (precancerous change) and no sign of cancer. Together, these features confirm the growth is a squamous papilloma.

Surgical margins

If the papilloma was removed by excision, the report may comment on the margin, the cut edge of the removed tissue.

Negative (clear) margin. No papilloma tissue at the cut edge. The growth appears to have been completely removed.
Positive margin. Papilloma tissue reaches the cut edge, so a small amount may remain. Because a papilloma is benign, this is not dangerous. It only means the growth could slowly return at the same spot.

For a benign growth like a papilloma, a positive margin does not carry the weight it would for a cancer. It is not a sign of spread, only a possible reason the growth could come back over time.

What happens after the diagnosis?

Once a squamous papilloma has been removed, no further treatment is usually needed. The result confirms the diagnosis, and the growth itself is gone. A squamous papilloma will not turn into cancer, so ongoing cancer surveillance is not required.

Papillomas caused by HPV can occasionally return, or a new one can form nearby, if other squamous cells in the area are also infected with the virus. If this happens, the new growth can be removed in the same simple way. Any new or persistent growth in the mouth should be checked, even if a papilloma was diagnosed before, because other kinds of oral growths can occasionally look similar.

Questions to ask your doctor

Was the papilloma completely removed?
Was it related to HPV?
Could it come back, or could new growths appear nearby?
Do I need a follow-up appointment?
Should I return if I notice any new or changing growths in my mouth?