What is Cancer?

What Is Cancer?

Cancer - it's a word that packs a powerful punch and causes a lot of confusion. But what many people don't realize is that cancer is a general term for a group of more than 100 diseases. The common factor of all those diseases is the uncontrolled growth and spread of abnormal cells.

All of our organs are made up of cells that divide to produce more cells when the body needs them. This is normal and healthy. But if cells divide when there is no need for new ones, they form a mass of tissue. That excess mass is considered a tumour. Tumours can be benign (noncancerous) or malignant (cancerous).

The cells in malignant tumours sometimes move outside their place of origin and damage nearby tissues and organs. These cancer cells also can break away from a malignant tumour and travel through the bloodstream or the lymphatic system to form new tumours in other parts of the body. This spread of the cancerous cells is called metastasis.

The Good News

Because significant progress has been made in the understanding of cancer and its treatment, those diagnosed now have a better chance of survival than ever before.

Just look at this comparison of survival rates from the American Cancer Society. In the 1930s, fewer than 1 in 5 survived to 5 years after treatment. In the 1940s, it was 1 in 4, and in the 1960s, it was 1 in 3. Now, 1 out of 2.5 patients who get cancer will celebrate their survival 5 years after their diagnosis.

Note the remarkable gains made in prostate and breast cancer survival rates. The 5-year survival rate for men diagnosed with prostate cancer is 93%. When the disease is confined to the breast, the 5-year breast cancer survival rate is more than 95%.

Currently, though many cancers can't be cured, there are several ways to arrest growth of cancerous cells and shrink or eliminate the existing tumours. Today, about 50 anti-cancer drugs are on the market, and companies are researching more than 300 medications for cancer and cancer-related conditions.

Cancer Treatments

Chemotherapy is the most common form of cancer treatment, with 90% of all cancer patients undergoing it.

Besides chemotherapy, the types of treatment most often used are surgery (removing the cancer in an operation), radiation therapy (using high-dose x-rays to kill cancer cells), hormone therapy (using drugs that change how hormones work or removing organs that produce hormones) and biological therapy (using the body's immune system to fight cancer).

Less frequently used options include radiosurgery, where radiation is focused right on the tumour, cryosurgery that freezes the tumour and kills it, photodynamic therapy with a light and special chemical that destroys cancerous cells and laser therapy with a narrow light beam that kills cancer cells.