The type of a cancer means the type of cell it started in. The grade tells you how much the cancer cells look like normal cells.
Cancers that start in skin like tissue (squamous cell cancer)
More than 90 out of every 100 laryngeal cancers (more than 90%) are this type. The cancer develops in the flat, skin like, squamous cells that cover the surface of the epiglottis, vocal cords and other parts of the larynx.
Cancers that start in gland cells (adenocarcinoma)
Adenocarcinoma is uncommon compared to squamous cell laryngeal cancer. It starts in the adenomatous cells that are scattered around the surface of the larynx. Adenomatous cells are gland cells that produce mucus.
The number of adenocarcinomas of the larynx has increased in the last 20 years, but we don't know why this is.
Other types of cancer found in the larynx
Very rarely, other types of cancer occur in the larynx. The treatment for these is completely different to the treatment described in this section.
Sarcomas of the larynx are extremely rare. Sarcomas are cancers that start in the body’s connective tissues.
Connective tissues are the supporting tissues of the body, such as bone, muscle, and nerves. Cartilage is the supporting tissue of the larynx. Cancers that develop from cartilage are called chondrosarcomas.
It’s also possible to get lymphoma in the larynx.
And it's possible to get plasmacytoma in the larynx. This is a type of myeloma.
Non cancerous changes in the voice box
Many diseases of the larynx aren’t cancer. Here are some conditions which affect the larynx that aren't cancerous.
Chronic laryngitis or swelling of the voice box lining is usually caused by:
- smoking – the larynx is irritated by the smoke, resulting in inflammation
- acid reflux – acid from the stomach leaks up into the food pipe (oesophagus)
- postnasal drip – mucus from the back of the nose running down the throat
- straining the voice – this can occur in people who use their voices a lot, for example, singers, teachers and sports coaches
Your doctor can tell you how to deal with chronic laryngitis. You may need a biopsy if your doctor wants to rule out any risk of your laryngitis being caused by a cancer.
Growths that are not cancer are called benign tumours. They can cause similar symptoms to laryngeal cancer. There are several types of rare benign tumours of the larynx, including:
- giant cell tumours
- granular cell tumours
- benign tumours of muscle (rhabdomyomas and leiomyomas)
- benign tumours of nerves (schwannomas)
Nodules are overgrowths of tissue on the vocal cords. They may be caused by smoking, acid reflux and straining the voice. They’re a more common cause of hoarseness than benign tumours. They don't usually need much treatment, apart from speech therapy and treatment for acid reflux, if that’s the cause.
The human papillion virus (HPV) can cause wart like growths on your larynx. These aren’t cancer, they’re papillomas or papillary growths. If you’ve papillomas that keep coming back, you may have an increased risk of laryngeal cancer later in life.
The grade of your cancer
The grade of a cancer tells you how much the cancer cells look like normal cells under a microscope. Doctors also use the term differentiation to describe how developed or mature a cell is.
There are 3 grades of laryngeal cancer:
- Grade 1 (low grade) - the cancer cells look very much like normal larynx cells (they are well differentiated)
- Grade 2 (intermediate grade) - the cancer cells look slightly like normal larynx cells (they are moderately differentiated)
- Grade 3 (high grade) - the cancer cells look very abnormal and don't look like normal larynx cells (they are poorly differentiated)
The grade of a cancer gives your specialist an idea about how the cancer is likely to behave.
Low grade cancers are usually slower to grow and less likely to spread. This is only a guide, your specialist will consider this, along with all of your test results when deciding which treatment is best for you.