Diagnosis & staging
The larynx has three parts:
- Glottis: Has two "true" vocal cords. These are narrow bands that vibrate to make sound. Our tongue, mouth and lips turn that sound into words.
- Supraglottis: Area from the vocal cords to the base of the tongue.
- Subglottis: Area between vocal cords and top of trachea.
If laryngeal cancer is found and treated early, it is very curable. This type of cancer grows slowly.
Laryngeal cancer may also be called:
- Throat cancer.
- Cancer of the voice box or vocal cords.
- Cancer of the glottis or subglottis.
- Glottic cancer.
- Supraglottic cancer.
- Larynx cancer or cancer of the larynx.
The most common symptom is voice hoarseness ("raspy" voice) or a change in your voice that does not go away.
If any of the following symptoms last for more than a few weeks, please see your family doctor or nurse practitioner:
- Lump or swelling in your throat.
- Pain when you swallow.
- Trouble swallowing.
- Earache (pain in your ear).
- Cough.
- Trouble breathing.
If you have any signs or symptoms that you are worried about, please talk to your family doctor or nurse practitioner.
Tests that may help diagnose laryngeal cancer include:
- Physical exam.
- Exam by head and neck specialist (otolaryngologist): Doctor will use a mirror (indirect laryngoscopy) or an endoscope (thin tube with a light and camera at the end) to look down your throat.
- Biopsy: This is when a doctor takes a sample of your tissue. A specialty doctor (pathologist) examines the tissue for cancer. The biopsy is usually done under general anaesthetic (when you are "put under").
- Imaging: to see the tumour and if cancer has spread.
- X-rays.
- CT (computed tomography) scan.
- MRI (Magnetic Resonance Imaging).
- PET (Positron Emission Tomography) scan.
- Ultrasound.
Most laryngeal cancers are carcinomas. These are cancers that start in the cells that line the larynx (squamous cells). How the cancer grows depends on where it starts.
The most common type of laryngeal cancer is cancer of the vocal cords (glottis). These usually grow slowly. In the early stage, they do not usually spread to other parts of the body.
Cancers of the subglottis are rare. Only 1-8% (1-8 in 100) of all laryngeal cancers are this type. This type of cancer is most likely to spread to other parts of the body in the early stages.
Cancers of the supraglottis are also rare. They are likely to spread, usually to the lymph nodes in the neck.
Staging describes the cancer. Staging is based on how much cancer is in the body, where it was first diagnosed, if the cancer has spread and where it has spread to.
The stage of the cancer can help your health care team plan your treatment. It can also tell them how your cancer might respond to treatment and the chance that your cancer may come back (recur).
- Stage 1: The cancer is in one part of the supraglottis.
- Stage 2: One of the following:
- The cancer is in two parts of the supraglottis.
- The cancer has grown into the vocal cords.
- The cancer has grown into tissue just outside the supraglottis.
- Stage 3: One of the following:
- Cancer is only in the larynx but vocal cords cannot move (vocal cord fixation) or cancer has grown into areas near the larynx and vocal cords may not move.
- Cancer has spread to one nearby lymph node on the same side of the neck as the original tumour. Lymph node is not larger than 3 cm.
- Stage 1: Cancer is only in the vocal cords.
- Stage 2: Cancer has grown into the top of the larynx above the vocal cords, the bottom of the larynx below the vocal cords or both. Vocal cords do not move normally.
- Stage 3: One of the following:
- Cancer is only in the larynx but vocal cords cannot move (vocal cord fixation) or cancer has grown into areas near the larynx and vocal cords may not move.
- Cancer has spread to one nearby lymph node on the same side of the neck as the original tumour. Lymph node is not larger than 3 cm.
- Stage 1: Cancer is only in the subglottis.
- Stage 2: Cancer has grown into the vocal cords. Vocal cords may not move normally.
- Stage 3: One of the following:
- Cancer is only in the larynx but vocal cords cannot move.
- Cancer has spread to one nearby lymph node on the same side of the neck as the original tumour. Lymph node is not larger than 3 cm.
- This is the same for all cancers that start in the larynx.
- Stage 4 laryngeal cancers can be Stage 4A, 4B or 4C depending on these things:
- Which nearby areas the cancer has grown into.
- The number and size of the lymph nodes with cancer.
- If the cancer has grown outside lymph nodes (extranodal extension).
- If the lymph nodes are on the same side or opposite side of the neck as the original cancer, or on both sides of the neck
- If the cancer has spread to other parts of the body farther from the larynx (called distant metastasis)
The grade of the cancer describes how different the cancer cells look from normal cells and how fast the cancer cells are growing. A pathologist will give the cancer a grade after looking at the cells under a microscope.
Laryngeal cancer can be grade 1, 2, 3 or 4. The lower the number, the lower the grade.
Low grade: cells are abnormal but look a lot like normal cells. Low grade cancers usually grow slowly and are less likely to spread.
High grade: cells are abnormal and do not look like normal cells. High grade cancers usually grow more quickly and are more likely to spread.
The grade of the cancer can help your health care team plan your treatment.
