Key Cancer Facts
- 10 million people die from cancer every year.
- At least one third of common cancers are preventable.
- Cancer is the second-leading cause of death worldwide.
- 70 percent of cancer deaths occur in low-to-middle income countries.
- Millions of lives could be saved each year by implementing resource appropriate strategies for prevention, early detection and treatment.
- The total annual economic cost of cancer is estimated at $1.16 trillion.
What is cancer ?
- Cancer is a disease which occurs when changes in a group of normal cells within the body lead to uncontrolled, abnormal growth forming a lump called a tumor; this is true of all cancers except leukemia (cancer of the blood). If left untreated, tumors can grow and spread into the surrounding normal tissue, or to other parts of the body via the bloodstream and lymphatic systems, and can affect the digestive, nervous and circulatory systems or release hormones that may affect body function.
- Cancer tumors can be divided into three groups: benign, malignant or precancerous
- Benign tumors are not cancerous and rarely threaten life. They tend to grow quite slowly, do not spread to other parts of the body and are usually made up of cells quite similar to normal or healthy cells. They will only cause a problem if they grow very large, becoming uncomfortable or press on other organs – for example a brain tumor inside the skull.
- Malignant tumors are faster growing than benign tumors and have the ability to spread and destroy neighboring tissue. Cells of malignant tumors can break off from the main (primary) tumor and spread to other parts of the body through a process known as metastasis. Upon invading healthy tissue at the new site they continue to divide and grow. These secondary sites are known as metastases and the condition is referred to as metastatic cancer.
- Precancerous (or premalignant) describes the condition involving abnormal cells which may (or is likely to) develop into cancer.
Types of cancers
Cancer can be classified according to the type of cell they start from. There are five main types:
- Carcinoma – A cancer that arises from the epithelial cells (the lining of cells that helps protect or enclose organs). Carcinomas may invade the surrounding tissues and organs and metastasize to the lymph nodes and other areas of the body. The most common forms of cancer in this group are breast, prostate, lung and colon cancer.
- Sarcoma – A type of malignant tumor of the bone or soft tissue (fat, muscle, blood vessels, nerves and other connective tissues that support and surround organs). The most common forms of sarcoma are leiomyosarcoma, liposarcoma and osteosarcoma.
- Lymphoma and Myeloma – Lymphoma and Myeloma are cancers that begin in the cells of the immune system. Lymphoma is a cancer of the lymphatic system, which runs all through the body, and can therefore occur anywhere. Myeloma (or multiple myeloma) starts in the plasma cells, a type of white blood cell that produces antibodies to help fight infection. This cancer can affect the cell’s ability to produce antibodies effectively.
- Leukemia – Leukemia is a cancer of the white blood cells and bone marrow, the tissue that forms blood cells. There are several subtypes; common are lymphocytic leukemia and chronic lymphocytic leukemia.
- Brain and spinal cord cancers – these are known as central nervous system cancers. Some are benign while others can grow and spread.
Signs and symptoms of cancer
With so many different types of cancers, the symptoms are varied and depend on where the disease is located. However, there are some key signs and symptoms to look out for, including:
- Unusual lumps or swelling – cancerous lumps are often painless and may increase in size as the cancer progresses
- Coughing, breathlessness or difficulty swallowing – be aware of persistent coughing episodes, breathlessness or difficulty swallowing
- Changes in bowel habit – such as constipation and diarrhea and/or blood found in the stools
- Unexpected bleeding – includes bleeding from the vagina, anal passage, or blood found in stools, in urine or when coughing
- Unexplained weight loss – a large amount of unexplained and unintentional weight loss over a short period of time (a couple of months)
- Fatigue – which shows itself as extreme tiredness and a severe lack of energy. If fatigue is due to cancer, individuals normally also have other symptoms
- Pain or ache – includes unexplained or ongoing pain, or pain that comes and goes
- New mole or changes to a mole – look for changes in size, shape, or colour and if it becomes crusty or bleeds or oozes
- Complications with urinating – includes needing to urinate urgently, more frequently, or being unable to go when you need to or experiencing pain while urinating
- Unusual breast changes – look for changes in size, shape or feel, skin changes and pain
- Appetite loss – feeling less hungry than usual for a prolonged period of time
- A sore or ulcer that won’t heal – including a spot, sore wound or mouth ulcer
- Heartburn or indigestion – persistent or painful heartburn or indigestion
- Heavy night sweats – be aware of very heavy, drenching night sweats