Cancer is what we call diseases that belong to a group of more than 100 different physiological conditions. There are many kinds of cancer, but all cancers begin with abnormal cells growing out of control, and eventually can cause serious illness and death (if untreated).]
Everybody is the sum of the function of trillions of living cell. Normally, body cells grow, divide, and die in a somewhat predictable fashion. Early in a person’s life, cells divide quickly to facilitate growth. Once an individual reaches adulthood, most cells divide just to replace older cells that have worn out.
How cancer starts
Cancer cells grow out of control, on their own terms. This process is significantly different from regular cell growth. Death is no longer predictable when cancer is involved. The cells continue to grow and form additional abnormal cells. Cancer cells can even invade, or grow into, other tissues. Obviously, normal cells cannot and do not behave like this.
The body is comprised of many different kinds of cells. Many types of cancer can arise in the complex ecosystem that is the human body. Some kinds of cancer are more dangerous than others, and treatments can vary from condition to condition. Generally, early treatment is easier than late stage treatment. Cancers with easier treatment programs usually have a more positive outlook, or prognosis.
Cancer is not simply one condition. In each case, the doctor will want to know exactly what type of cancer has developed, how large the cancer has become or how far it has spread. Some of these factors will be indicative of whether or not the cancer will respond to treatment.
What are cells?
Understanding cancer requires an understanding of cells. Cells are the simplest unit of living matter. There are unicellular organisms like bacteria and multi cellular animals in every shape and size. In each instance, the cell is a basic organizing unit. The human body’s millions upon millions of cells perform a variety of functions. Some travel and some are stagnant. Different parts of the body have specialized cells. Bones have their own cells. Muscles have their own cells. The nervous system has highly specialized cells. Blood cells transport oxygen throughout the body to fuel other cell.
Each cell has a nucleus which contains thousands of genes which are made from a chemical called DNA. Genes are a sort of coding device that control the functions of the cell. For example, different genes control how a cell uses proteins and lipid and interacts with other cells. Some genes control how the cell develops and others control when the cell dies.
Most cells in the body must divide and multiply on a regular basis. As old cells wear out, new cells are formed to take their place. Different cells multiply at different rates. Millions of blood cells are born and die in your body every day. Conversely, brain cells live for a LONG time and rarely multiply.
Sometimes, a cell’s genes and DNA sequence become damaged. Perhaps the double helix molecular structure begins to break down for some reason. Imagine a rope fraying at the ends. Nucleic damage can result in cancerous cell growth. DNA is in every cell and directs every cell’s behaviour. When the DNA gets the damaged, it’s either repaired or the cell dies.
This isn’t the case for cancer cells. These abnormal cells just continue reproducing, using a faulty DNA sequence. So every subsequent cell is already damaged upon formation. These abnormal cells grow exponentially, from one to two to four to eight and so on. Then the cancer cells clump together in a growth called a tumour. This growth can be dangerous and painful. Other types of cancer such as leukaemia grow in the blood and do not form tumours. These simply circulate through the blood stream, destroying the body like that.
What are tumours?
A tumour is a lump or growth of tissue made up from abnormal cells. Tumours are divided into two types: benign and malignant. Sometimes can be surgically removed. Other tumours require more serious measures.
Benign tumours are labelled such because they are not harmful. Occasionally, there will be an aesthetic reason for their removal, but generally they don’t hurt anybody.
Benign tumours usually can’t spread to other parts of the body. They can form anywhere on the body, but they grow slowly and are non-invasive. We do not consider benign tumours cancerous and they are almost never life threatening. Generally these tumours do no harm if left alone, however some have been known to cause local pressure symptoms. Also, they might affect hormonal glands if growing too nearby.
Malignant tumours (cancers)
Malignant tumours are the opposite of benign tumours. They are ambitious, and not in a good way. These dangerous buggers have two goals: to survive and conquer new territory. Malignant tumours tend to grow quickly and invade nearby tissues and organs. This growth causes damage and can lead to a variety of undesirable health conditions.
Typically, tumours develop in one spot. This is called the primary tumour. Malignant tumours can metastasize and spread into secondary tumours. This happens when some cells break off from the primary tumour and are carried in the bloodstream or lymph channels to other parts of the body. These secondary tumours can grow into huge problems. They’ll invade nearby tissues just like the primary tumours.
Note: Not all cancers form solid tumours. For example, in cancer of the blood cells (leukaemia) many abnormal blood cells are made in the bone marrow and circulate in the bloodstream.