Introduction

This booklet is for you if you have or someone close to you has cancer of the larynx.

If you are a patient your doctor or nurse may wish to go through the booklet with you and mark sections that are particularly important for you.

The voicebox (larynx)

The voicebox, or larynx, is a tube-shaped structure, about 5cm (2in) long, which sits at the entrance to the windpipe (trachea).

It can be seen, or felt, as the normal lump in the front of the neck known as the Adam’s apple. There are three main parts to the larynx.

The supraglottis is the area above the vocal cords.
The glottis is the area containing the vocal cords.
The subglottis is below the vocal cords.

Air breathed in through the nose and mouth is warmed and moistened, and then passes through the larynx and down the windpipe to the lungs.

The larynx:

allows the air breathed in to reach the lungs
acts as a valve which closes to prevent food and drink entering the windpipe when you swallow
contains the two vocal cords, which vibrate together when air passes between them, to produce the sound of the voice.

The parts of the larynx

What is cancer?

The organs and tissues of the body are made up of tiny building blocks called cells. Cancer is a disease of these cells.

Cells in different parts of the body may look and work differently but most reproduce themselves in the same way. Cells are constantly becoming old and dying, and new cells are produced to replace them. Normally, cells divide in an orderly and controlled manner. If for some reason the process gets out of control, the cells carry on dividing, developing into a lump which is called a tumour.

Tumours can be either benign or malignant. Cancer is the name given to a malignant tumour. Doctors can tell if a tumour is benign or malignant by examining a small sample of cells under a microscope. This is called a biopsy.

In a benign tumour the cells do not spread to other parts of the body and so are not cancerous. However, if they continue to grow at the original site, they may cause a problem by pressing on the surrounding organs.

A malignant tumour consists of cancer cells that have the ability to spread beyond the original area. If the tumour is left untreated, it may spread into and destroy surrounding tissue. Sometimes cells break away from the original (primary) cancer. They may spread to other organs in the body through the bloodstream or lymphatic system.

The lymphatic system is part of the immune system - the body's natural defence against infection and disease. It is a complex system made up of organs, such as bone marrow, the thymus, the spleen, and lymph nodes. The lymph nodes (or glands) throughout the body are connected by a network of tiny lymphatic ducts.

When the cancer cells reach a new area they may go on dividing and form a new tumour. This is known as a secondary cancer or metastasis.

It is important to realise that cancer is not a single disease with a single type of treatment. There are more than 200 different kinds of cancer, each with its own name and treatment.

Types of cancer

Carcinomas

The majority of cancers, about 85% (85 in a 100), are carcinomas. They start in the epithelium, which is the covering (or lining) of organs and of the body (the skin). The common forms of breast, lung, prostate and bowel cancer are all carcinomas.

Carcinomas are named after the type of epithelial cell that they started in and the part of the body that is affected. There are four different types of epithelial cells:

• squamous cells - that line different parts of the body, such as the mouth, gullet (oesophagus), and the airways
• adeno cells - form the lining of all the glands in the body and can be found in organs such as the stomach, ovaries, kidneys and prostate
• transitional cells - are only found in the lining of the bladder and parts of the urinary system
• basal cells - that are found in one of the layers of the skin.

A cancer that starts in squamous cells is called a squamous cell carcinoma. A cancer that starts in glandular cells is called an adenocarcinoma. Cancers that start in transitional cells are transitional cell carcinomas, and those that start in basal cells are basal cell carcinomas.

Leukaemias and lymphomas

These occur in the tissues where white blood cells (which fight infection in the body) are formed, i.e. the bone marrow and lymphatic system. Leukaemia and lymphoma are quite rare and make up about 6.5% (6.5 in 100) of all cancers.

Sarcomas

Sarcomas are very rare. They are a group of cancers that form in the connective or supportive tissues of the body such as muscle, bone and fatty tissue. They account for less than 1% (1 in 100) of cancers.

Sarcomas are split into two main types:

• bone sarcomas - that are found in the bones
• soft tissue sarcomas - that develop in the other supportive tissues of the body.

Others forms of cancer

Brain tumours and other very rare forms of cancer make up the remainder of cancers.

Risk factors and causes of laryngeal cancer

There is no single cause of cancer of the larynx. It’s likely that several factors are involved. Not all of these risk factors are known, but research is ongoing into the possible causes.

Smoking and heavy drinking of alcohol (especially spirits) greatly increase the risk of developing cancer of the larynx.

Cancer of the larynx occurs mainly in middle-aged and older people, but it can occur in younger people who started smoking at an early age. It is much more common in men than in women.

It’s thought that the human papilloma virus (HPV) may play a part in the development of cancer of the larynx.

Exposure to certain chemicals such as formaldehyde, nickel, sulphuric acid mist and isopropyl alcohol may increase your risk of developing this cancer.

As with other cancers, cancer of the larynx is not infectious and can’t be passed on to other people.

How common is Cancer of Larynx in India?

Cancer of Larynx (voice box) is one of the common cancers among men from the Indian subcontinent. The incidence (newly diagnosed cases of Cancer in a year) of Cancer of Larynx for men from India is about 5 men per 1,00,000 population.

In India, between the years 2001-2003, across five urban centers - Mumbai, Delhi, Chennai, Bhopal and Bangalore, – and one rural center - Barshi, a total of 2,276 cases of Cancer of Larynx were registered (5.16% of all cancers) for males across all age groups; while 276 cases of Cancer of Larynx were registered (0.62% of all cancers) for females across all age groups. Considering all men, women and children with all types of cancers together, a grand total of 2,552 cases of Cancer of Larynx (2.88% of all cancers) were registered at the six centers mentioned above, between the year 2001-2003.

The TATA Memorial Hospital (T.M.H.) in Mumbai, India registered a grand-total of 19,127 cases of all types of cancer patients in the year 2006, for men, women and children combined, out of which 478 (2.5% of the total cases) were diagnosed with the Cancer of Larynx. Out of the total 478 patients diagnosed with Cancer of Larynx, mentioned above at the T.M.H., 445 (93%) were males and 33 (7%) were females.