Author : Bhadresh Bundela
Breast cancer explained :
The term breast cancer actually refers to a large family of cancers that can develop in any part of the breast tissue. The most common types of breast cancer start in the glandular tissue - and the most common of all in the ducts.
Understanding cells
Our bodies are made up of tiny structures called cells, which are not visible to the naked eye. Groups of cells form the tissues and organs of the body and each of these, such as the brain, liver, kidneys and lungs, has a unique function. Normally, cells reproduce themselves by dividing in a regular, orderly fashion so that growth and repair of body tissues can take place. Disease can disrupt this normal function in various ways.
Tumours
Sometimes there is an uncontrolled growth of cells causing a swelling or tumour. Tumours that remain contained within a limited area are called benign. Once treated, often by an operation, these don't usually cause any further problems. Cancers, or malignant tumours, also start within a limited area but unlike benign tumours they have the ability to spread to nearby organs or tissues, or to more distant parts of the body. This spread is known as metastasis, or secondary cancer. The area where the cancer originated, for instance the breast, is called the primary cancer.
How cancer develops
Cancer develops from one single cell. Normally, cells are controlled by a variety of in-built safety catches that make sure that each cell grows and behaves as it should.A cell can become cancerous in a number of ways:
The cell becomes 'switched on' to divide, and does not have a functioning safety catch to stop the process, so the cell can carry on dividing.
-->The cell becomes unable to recognise damage to DNA (the chemical code for a cell) or does not have the ability to repair any damage, so the cell continues to live with a faulty 'instruction manual'.
-->The cell can lose its ability to sense neighbouring cells and interact with them normally. The proteins that normally play a part in controlling these processes may become damaged. This can lead to cells behaving abnormally and multiplying out of control. When cells are dividing too much they can go on to form a lump, a characteristic of many cancers, including breast cancer.
Understanding genes
The human body is made up of tiny building blocks called cells. Cells are made up of even smaller building blocks, which form the cell's structure and control its behaviour. These building blocks are called proteins - and genes largely govern their construction and consequent behaviour.A gene is a coded message made up of DNA, the chemical that carries the instructions for making living organisms, and is passed from parent to child.Just as words are made up of strings of 26 different letters, DNA is made up of strings of 4 different chemicals called nucleotides. In language, strings of letters form words and sentences; in genetics, strings of nucleotides form genes. Each gene then carries the blueprint for building a specific protein with a specific role to play in the cell.Cells normally divide many times during their normal lifespan, and each time the 'spelling' of the DNA for each gene is meticulously copied. But sometimes a spelling mistake occurs: we say the gene has acquired a mutation. If the mutation occurs in a critical part of the blueprint, it can cause the resulting protein to be abnormal or damaged in some way.Mutations can be inherited, be triggered by cancer-causing agents in the environment, or result from rare errors when DNA is being copied or repaired. A single mutation in a gene may not impact the behaviour of that protein or in turn the cell. But scientists believe that when a person accumulates several of these genetic errors, cancer can occur.
How cancer spreads
The body has two transport systems, the blood and the lymphatic system. The lymphatic system normally helps the body to fight infection. It is made up of a series of nodes (glands) and vessels (tubes) linked throughout the body.Breast cancer cells can break away from the original lump, move through surrounding tissue, and eventually be carried by the body's transport systems to other parts of the body. Breast cancer cells can spread to the lymph nodes in the armpit. In fact, involvement of the lymph nodes can be an indication of how likely it is for the cancer to return.Cancer cells can also be carried in the bloodstream to distant sites in the body. Here they may form new tumours called metastases or 'secondaries'. If breast cancer spreads to another part of the body, cure is no longer possible. However, treatments can control secondary disease, sometimes for a long time.
Secondary breast cancer
Secondary cancer is when cancer cells from the breast have spread and established themselves in other parts of the body. This spread is called metastasis and cancer that has spread is said to have metastasised. In breast cancer, the spread is most often to the bones, lungs or liver. The original (or primary) cancer is in the breast. The secondary cancer is still breast cancer, but it has invaded a different part of the body and become established there.
