Cancer is a disease of the cells in the body. There are many different types of cell in the body, and many different types of cancer which arise from different types of cell.
What is cancer?
What all types of cancer have in common is that the cancer cells are abnormal and multiply out of control. However, there are often great differences between different types of cancer.
Some grow and spread more quickly than others and some are easier to treat than others, particularly if diagnosed at an early stage.
Some respond much better than others to chemotherapy, radiotherapy, or other treatments, while some have a better outlook (prognosis) than others. For some types of cancer there is a very good chance of being cured. For some types of cancer, the outlook is poor.
So, cancer is not just one condition. In each case it is important to know exactly what type of cancer has developed, how large it has become, whether it has spread and how well the particular type of cancer responds to various treatments. This will enable you to get reliable information on treatment options and outlook.
What are the different types of cancer?
There are more than 100 different types of cancer. Each type is classified by the type of cell the cancer originates from. For example, a breast cell, a lung cell, etc. Each type of cancer generally falls into one of three categories:
- Carcinomas are cancers that arise from cells which line a body surface, or the lining of a gland – for example, the skin, or the lining of the gut, mouth, neck of the womb (cervix), airways, etc.
- Sarcomas are cancers that arise from cells which make up the connective tissues such as bones or muscles. For example, an osteosarcoma is a cancer of bone tissue.
- Leukaemias and lymphomas are cancers of cells in bone marrow and lymph glands. For example, leukaemiais a cancer of cells that make white blood cells.
- Bladder Cancer
- Brain Cancer and Brain Tumours
- Breast Cancer
- Cancer of the Uterus (Endometrial Cancer)
- Cervical Cancer
- Childhood Leukaemia
- Colon, Rectal and Bowel Cancer (Colorectal Cancer)
- Gynaecological Cancer
- Hodgkin’s Lymphoma
- Kidney Cancer
- Lung Cancer
- Mouth Cancer (Oral Cancer)
- Neck Lumps and Bumps
- Non-Hodgkin’s Lymphoma
- Oesophageal Cancer
- Ovarian Cancer
- Pancreatic Cancer
- Penile Cancer
- Primary Bone Cancer
- Primary Liver Cancer
- Prostate Cancer
- Scrotal Lumps, Pain and Swelling
- Skin Cancer (Melanoma)
- Skin Cancer (Non-Melanoma)
- Stomach Cancer (Gastric Cancer)
- Testicular Cancer
- Throat Cancer (Laryngeal Cancer)
- Thyroid Cancer
- Vulval Cancer
- Wilms’ Tumour
What are cancer symptoms?
Cancer symptoms will vary according to the type of cancer and how far the cancer has grown. There are some symptoms that are common to many cancers and are the result of the increased cell turnover. These include:
- Weight loss – in severe cases there can be both loss of fat and muscle, leading to a wasting condition called cachexia.
- Loss of appetite.
- Pale skin and paleness of the inside of the lower eyelid, a low blood count (anaemia).
Other symptoms you may be asked about include:
- Any visible loss of blood.
- Any unexplained lumps or bumps.
You may also be asked about more specific features, depending on which underlying cancer is suspected such as:
- Breast cancer: breast lump, nipple discharge, change in skin.
- Bowel cancer: blood in stools or after passing stool, pain in rectum.
- Lung cancer: persistent cough, blood in sputum (haemoptysis), chest pain.
- Brain cancer: unexplained headaches; headache present on waking, feeling sick (nausea), being sick (vomiting), abnormal sensations or weakness in the limbs.
Cancer findings on examination
Features on examination may also help determine if cancer is present and if so where it is. This may include the following:
- Features of excessive weight loss.
- Evidence of anaemia – pale skin and pallor inside the lower eyelid.
- Any enlarged lymph nodes such as in the neck or under the armpits. The cancer cells will have a blood supply and toxins will pass into the veins and also the lymph channels. This toxic product can then build up and lead to enlargement of the lymph nodes.
- Raised temperature (fever) – some cancers can lead to high fever (for example, lymphoma).
- Enlargement of the liver which is knobbly in nature and may be the result of cancer spreading to the liver (metastases).
- Lump of cancer – for example, in the breast in breast cancer or in the abdomen in bowel cancer.
It is important to note that often there may be nonspecific symptoms or even no symptoms. If you are worried, you should see your healthcare physician and discuss your symptoms further.
Treatment options vary, depending on the type of cancer and how far it has grown and spread. The main types are surgery, chemotherapy and radiotherapy.
What are the treatment options for cancer?
Treatment options vary, depending on the type of cancer and how far it has grown and spread. See the separate leaflets on the specific cancers for more details.聽There is also another leaflet called Staging and Grading Cancer, which discusses how a cancer is classified depending on its type (grading) and how far it has spread in the body (staging). Briefly, the three most common treatments are:
- Surgery. It may be possible to cut out a cancerous (malignant) tumour.
- Chemotherapy. This is a treatment that uses anti-cancer medicines to kill cancer cells, or to stop them from multiplying. There are various different types of medicines used for chemotherapy. The medicine or combination of medicines selected depends on the type of cancer being treated.
- Radiotherapy. This is a treatment that uses high-energy beams of radiation which are focused on cancerous tissue. This kills cancer cells, or stops cancer cells from multiplying.
More recently, other treatments have been introduced which include:
- Stem cell transplant. High-dose chemotherapy may damage bone marrow cells and lead to blood problems. However, if you receive healthy bone marrow after the chemotherapy then this helps to overcome this problem.
- Hormone therapy. This is the use of medicines to block the effects of hormones. This treatment may be used for cancers that are hormone-sensitive such as some cancers of the breast, prostate and womb (uterus).
- Immunotherapy. Some treatments can boost the immune system to help to fight cancer. More specific immunotherapy involves injections of antibodies which aim to attack and destroy certain types of cancer cells. Research is underway to try to find vaccines that would stimulate your own immune system to make antibodies against cancer cells.
- Gene therapy. This is a new area of possible treatments. Research is underway to find ways of blocking, repairing or replacing abnormal genes in cancer cells.
- Special techniques. These can sometimes be used to cut off the blood supply to tumours. The tumour then dies.
What is cancer staging?
The stage of a cancer is a measure of how much the cancer has grown and spread. Some cancers are also graded by looking at features of the cancer cells, using a microscope or other tests. The stage and grade of a cancer help to say how advanced it is, and how well it may respond to treatment. As a general rule, the earlier the stage and the lower the grade of a cancer, the better the outlook (prognosis). A common way of staging cancer is called the TNM classification:
- T stands for tumour – how far the primary tumour has grown locally.
- N stands for nodes – if the cancer has spread to the local lymph glands (nodes).
- M stands for metastases – if the cancer has spread to other parts of the body.
When a cancer is staged, a number is given for each of these three characteristics. For example, in stomach cancer:
- T-1 means the primary tumour is still in the stomach wall. T-3 means the primary tumour has grown right through the stomach wall and T-4 means it is invading nearby structures such as the pancreas.
- N-0 means there is no spread to lymph nodes. N-1 means that some local lymph nodes are affected. N-2 means more extensive spread to local lymph nodes.
- M-0 means there are no metastases. M-1 means that there are metastases to some other area of the body such as the liver or brain.
So, for a certain case of stomach cancer, a doctor may say something like: “The stage is T-3, N-1, M-0.” This means that the cancer has spread through the stomach wall, there is some spread to local lymph nodes, but no metastases in other parts of the body.
There are other staging classifications which are sometimes used for various cancers. For example, a number system is used for some cancers. That is, a cancer may simply be said to be stage 1, 2, 3 or 4 (or stage I, II, III, or IV). Again, the stages reflect how large the primary tumour has become and whether the cancer has spread to lymph nodes or other areas of the body. It can become complicated as each number may be subdivided into a, b, c, etc. For example, you may have a cancer at stage 3b. A grade 4 stage is often referred to as an advanced cancer.