HPV-Associated Dysplasia of the Larynx: Understanding Your Pathology Report

Section Editor: Jason Wasserman MD PhD FRCPC
July 26, 2026

HPV-associated dysplasia of the larynx is a precancerous change in the lining of the voice box caused by infection with the human papillomavirus (HPV). Dysplasia means the squamous cells lining the larynx have started to grow and mature abnormally. It is not cancer, but over time it can develop into a type of laryngeal cancer called squamous cell carcinoma.

This condition can affect any part of the larynx, but it develops most often on the vocal cords, in the region called the glottis. It is uncommon. Most dysplasia of the larynx is caused by tobacco and alcohol rather than by HPV, and that far more common form is described in the article on keratinizing squamous dysplasia of the larynx. The two look different under the microscope, are tested for differently, and are not graded the same way, so establishing which one you have is an important part of the diagnosis.

This article explains the findings you are likely to see on a pathology report for HPV-associated dysplasia of the larynx, what each one means, and why it matters for your care.

What causes HPV-associated dysplasia of the larynx?

HPV-associated dysplasia of the larynx is caused by a lasting infection with high-risk HPV, most often type 16. HPV is a very common virus that infects squamous cells lining the throat, mouth, and other surfaces of the body. There are more than 100 types. Most cause no lasting harm and are cleared by the immune system within a year or two, and only a small number of high-risk types can persist and cause disease.

When a high-risk type is not cleared, it switches off the cell’s tumor suppressor genes, which normally act as brakes that stop cells from dividing when they should not. With those brakes disabled, the cells grow abnormally, and over time this can lead to dysplasia and eventually to cancer. This is the same process by which high-risk HPV causes precancerous changes in the oropharynx, the cervix, and the anal canal.

HPV spreads through direct skin-to-skin contact, including sexual and oral-genital contact. Most sexually active adults will have at least one HPV infection in their lifetime, and the large majority clear it without any lasting change.

What are the symptoms of HPV-associated dysplasia of the larynx?

Many people with HPV-associated dysplasia of the larynx have no symptoms early on. Because the change usually develops on the vocal cords, the most common symptom when one appears is a change in the voice, since even a small abnormal area interferes with the way a vocal cord vibrates. Symptoms may include:

Hoarseness or a change in the voice, often the first and only symptom
Throat discomfort or pain
Difficulty swallowing
A lasting cough
Noisy breathing or shortness of breath, only when a larger area is involved

Any change in the voice lasting more than two to three weeks should be assessed by an ear, nose, and throat specialist.

How is the diagnosis made?

The diagnosis is made when a pathologist examines tissue from the abnormal area under the microscope. The tissue is obtained by biopsy during a procedure called microlaryngoscopy, in which a thin scope is passed through the mouth under general anesthetic so the surgeon can see the vocal cords directly and take a sample or remove the abnormal area.

Under the microscope, the pathologist looks for abnormal squamous cells in the surface lining and confirms that they have not grown down into the tissue beneath. That downward growth is called invasion, and its absence is what separates dysplasia from an invasive cancer.

Your report may describe the dysplasia as nonkeratinizing. This means the abnormal cells are not producing keratin, a tough surface protein, which under the microscope gives them a blue appearance. It is a useful clue, because dysplasia caused by tobacco and alcohol usually does produce keratin and appears pink instead. Testing for HPV, described in the next section, is then used to confirm the cause.

p16 and HPV testing

Because the appearance under the microscope alone cannot establish that HPV is the cause, testing is performed on the tissue and the results appear on your pathology report. You may see one or both of the following:

p16: positive. p16 is a protein that builds up in large amounts inside cells infected with high-risk HPV, so it is used as a stand-in marker for the virus. It is measured using immunohistochemistry, a test that uses antibodies to detect specific proteins in tissue. A positive result supports the diagnosis and is the expected finding here.
HPV in situ hybridization or PCR: positive. These tests detect the virus’s genetic material directly inside the cells and can identify the specific type. They are more specific than p16 and are often used to confirm it.

Not every case needs both tests, so a report showing only one is not incomplete. It is worth knowing that p16 is used somewhat differently in the larynx than in the oropharynx. In the oropharynx, a positive p16 result on its own is generally accepted as evidence of HPV. In the larynx, where HPV is a much less common cause, a positive p16 result is more often confirmed with a test that detects the virus directly before the diagnosis is settled.

Is HPV-associated dysplasia of the larynx given a histologic grade?

No. Unlike dysplasia of the larynx caused by tobacco and alcohol, which is divided into low-grade and high-grade, HPV-associated dysplasia is generally not assigned a grade. If you are looking for a grade on your report and cannot find one, nothing has been left out.

The reason is that grading has not been shown to predict the risk of cancer developing in this particular condition, so assigning one would give a number that does not mean much. For this diagnosis, what matters is that the dysplasia is present, whether it has been completely removed, and that the area is followed over time.

Surgical margins

When the abnormal area is removed rather than just sampled, the report may describe the margins, the cut edges of the tissue removed.

Negative (clear) margin. No dysplasia at the cut edge. The abnormal area appears to have been completely removed.
Positive (involved) margin. Dysplasia reaches the cut edge, meaning some abnormal tissue may remain. Your doctor will discuss whether further treatment is needed.
Cannot be assessed. The tissue was fragmented, or the edges were cauterized during removal, which is common with laser procedures. This does not mean the procedure was inadequate, but it makes careful follow-up more important.

In the larynx, there is a particular consideration. The surgeon works to remove the abnormal area while preserving as much normal vocal cord as possible, because removing too much tissue affects the voice. A clear margin also does not eliminate the risk entirely, since surrounding lining may still carry the virus, which is why follow-up continues regardless of what the margins show.

What is the risk that HPV-associated dysplasia will turn into cancer?

HPV-associated dysplasia of the larynx is a precancerous change, and without treatment it carries some risk of developing into squamous cell carcinoma over time. The honest answer about how much risk is that it is not yet well established. This condition is uncommon, so the available studies are small, and there is not enough evidence to give a reliable percentage.

What the limited data suggest is that the risk appears lower than for dysplasia of the larynx caused by tobacco and alcohol. This fits with what is seen elsewhere in the head and neck, where HPV-associated disease generally behaves more favorably than disease caused by smoking and drinking. Even so, the risk is real enough that removal and ongoing follow-up are recommended.

What happens after the diagnosis?

Treatment is usually complete removal of the abnormal area, most often using a laser through a scope passed into the throat, performed by an ear, nose, and throat surgeon. Removal serves two purposes: it takes out the abnormal tissue, and it allows the whole area to be examined so an unsuspected early cancer is not missed.

Follow-up examination of the larynx is important even when the area has been completely removed, because a lasting HPV infection in the surrounding lining means new areas of dysplasia can develop over time. Your specialist will advise how often, and follow-up generally continues for years rather than a fixed period. If the dysplasia returns or a new area appears, another procedure may be needed.

If you smoke or drink alcohol, stopping or cutting back is recommended, because tobacco and alcohol are separate risk factors that can speed the progression of laryngeal dysplasia to cancer regardless of the role HPV has played. Voice therapy with a speech-language pathologist may also be offered if your voice has changed after a procedure on the vocal cords.

Finally, the HPV vaccine is highly effective at preventing infection with the high-risk types that cause dysplasia and cancer. It cannot treat an infection you already have, but it can protect people who have not yet been exposed, so it may be relevant for family members who have not been vaccinated.

Questions to ask your doctor

Was HPV confirmed, and which tests were used?
Where in my larynx is the abnormal area, and how much is involved?
Was the whole area removed, or was only a sample taken?
If it was removed, were the margins clear?
Was there any sign of invasive cancer?
My report has no grade. Is that expected for this diagnosis?
What is my risk of developing cancer, and how will it be monitored?
How often will my larynx be examined, and for how long?
Will my voice be affected, and would voice therapy help?
Would stopping smoking or reducing alcohol lower my risk?
Is HPV vaccination relevant for anyone in my family?
What changes should prompt me to call before my next visit?