Cancer is a condition where cells in a specific part of the body grow and reproduce uncontrollably. The cancerous cells can invade and destroy surrounding healthy tissue, including organs.
=> Cancer sometimes begins in one part of the body before spreading to other areas. This process is known as metastasis.
=> In a normal situation, cells develop, divide and die. These normal cells develop and divide less and less as we grow older, until they only divide when needed i.e. To replace dead or dying cells and to heal injuries.
=> Cancerous cells on the other hand, have a longer life span then the average cell. Giving the cancerous cells more time to multiply, which is why early treatment for cancer is essential to stop the growth of the cancerous cells and to give the patient a higher chance of survival.
=> The process of cancer cells traveling through the body, either through the blood stream or lymph vessels, is called metastasis. Once these cancer cells have arrived at their destination, they start to grow and replace the regular surrounding tissue. This is how the tumors are formed. Tumors are not typical to all cancers. Leukemia is an exception, cancerous cells from leukemia only travel through the blood stream and blood-forming organs, growing onto tissue and replacing, just like other cancers, except no tumor is formed.
=> Not all tumors are cancerous though. Noncancerous or 'Benign' tumors do not spread throughout the body and, generally speaking, are not life threatening.
Figur: The Biology of Cancer
=> It is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. Not all tumors are cancerous; benign tumors do not spread to other parts of the body. Possible signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss and a change in bowel movements. While these symptoms may indicate cancer, they may have other causes. Over 100 cancers affect humans.
=> Many cancers can be prevented by not smoking, maintaining a healthy weight, not drinking too much alcohol, eating plenty of vegetables, fruits and whole grains, vaccination against certain infectious diseases, not eating too much processed and red meat, and avoiding too much sunlight exposure. Early detection through screening is useful for cervical and colorectal cancer. The benefits of screening in breast cancer are controversial. Cancer is often treated with some combination of radiation therapy, surgery, chemotherapy, and targeted therapy. The chance of survival depends on the type of cancer and extent of disease at the start of treatment. In children under 15 at diagnosis the five-year.
Oldest descriptions of cancer:
Figure: Oldest example of cancer found
Human beings and other animals have had cancer throughout recorded history. So it’s no surprise that from the dawn of history people have written about cancer. Some of the earliest evidence of cancer is found among fossilized bone tumors, human mummies in ancient Egypt, and ancient manuscripts. Growths suggestive of the bone cancer called osteosarcoma have been seen in mummies. Bony skull destruction as seen in cancer of the head and neck has been found, too.
Our oldest description of cancer (although the word cancer was not used) was discovered in Egypt and dates back to about 3000 BC. It’s called the Edwin Smith Papyrus and is a copy of part of an ancient Egyptian textbook on trauma surgery. It describes 8 cases of tumors or ulcers of the breast that were removed by cauterization with a tool called the fire drill. The writing says about the disease, “There is no treatment.”
Origin of the word cancer:
The origin of the word cancer is credited to the Greek physician Hippocrates (460-370 BC), who is considered the “Father of Medicine.” Hippocrates used the terms carcinos and carcinoma to describe non-ulcer forming and ulcer-forming tumors. In Greek, these words refer to a crab, most likely applied to the disease because the finger-like spreading projections from a cancer called to mind the shape of a crab. The Roman physician, Celsus (28-50 BC), later translated the Greek term into cancer, the Latin word for crab. Galen (130-200 AD), another Greek physician, used the word oncos (Greek for swelling) to describe tumors. Although the crab analogy of Hippocrates and Celsus is still used to describe malignant tumors, Galen’s term is now used as a part of the name for cancer specialists – oncologists.
Cancer in the sixteenth to eighteenth centuries:
During the Renaissance, beginning in the 15th century, scientists developed greater understanding of the human body. Scientists like Galileo and Newton began to use the scientific method, which later was used to study disease. Autopsies, done by Harvey (1628), led to an understanding of the circulation of blood through the heart and body that had until then been a mystery.
In 1761, Giovanni Morgagni of Padua was the first to do something which has become routine today – he did autopsies to relate the patient’s illness to pathologic findings after death. This laid the foundation for scientific oncology, the study of cancer.
The famous Scottish surgeon John Hunter (1728-1793) suggested that some cancers might be cured by surgery and described how the surgeon might decide which cancers to operate on. If the tumor had not invaded nearby tissue and was “moveable,” he said, “There is no impropriety in removing it.”
Cancer in the nineteenth century:
Figure: Cancer in the nineteenth century
The 19th century saw the birth of scientific oncology with use of the modern microscope in studying diseased tissues. Rudolf Virchow, often called the founder of cellular pathology, provided the scientific basis for the modern pathologic study of cancer. As Morgagni had linked autopsy findings seen with the unaided eye with the clinical course of illness, so Virchow correlated microscopic pathology to illness.
This method not only allowed a better understanding of the damage cancer had done, but also aided the development of cancer surgery. Body tissues removed by the surgeon could now be examined and a precise diagnosis could be made. The pathologist could also tell the surgeon whether the operation had completely removed the cancer.
Cancer in the twenty-first century:
Figure: Avoidable global cancer deaths and total deaths from smoking
The growth in our knowledge of cancer biology has led to remarkable progress in cancer prevention, early detection, and treatment. Scientists have learned more about cancer in the last 2 decades than had been learned in all the centuries preceding. This doesn’t change the fact, however, that all scientific knowledge is based on the knowledge already acquired by the hard work and discovery of our predecessors – and we know that there’s still a lot more to learn.
Cancer research is advancing on so many fronts that it’s hard to choose the ones to highlight, but here are a few examples:
More targeted therapies:
As more is learned about the molecular biology of cancer, researchers will have more targets for their new drugs. Along with more monoclonal antibodies and small signaling pathway inhibitors, researchers are developing new classes of molecules such as antisense oligodeoxynucleotides and small interfering RNA (siRNA). Research is being done to develop targeted drugs that are aimed at proteins produced by specific gene mutations in cancer cells, too.
More on cancer genetics:
Researchers are looking for gene mutations that cause some patients to respond better to certain drugs.
Nanotechnology:
New technology for producing materials that form extremely tiny particles is leading to very promising imaging tests that can more accurately show the location of tumors. It also is aiding the development of new ways to deliver drugs more specifically and effectively to cancer cells.
Robotic surgery:
This term refers to manipulation of surgical instruments remotely by robot arms and other devices controlled by a surgeon. Robotic systems have been used for several types of cancer surgery; radical prostatectomy is among the most common uses in surgical oncology. As mechanical and computer technology improve, some researchers expect future systems will be able to remove tumors more completely and with less surgical trauma.
** Currently, cancer is the second biggest killer in the United States with 1 out of every 2 men developing cancer throughout their lifetimes, while 1 out of every 3 women will develop a form of cancer.Many studies have been done into how a healthy lifestyle and eating habits help lower a person risk of getting a cancer. Quitting smoking, cutting out the alcohol, eating a healthy balanced diet, regular exercise greatly help your chance of not getting cancer.
** If you are worried that you may have cancer or perhaps, have a history of cancer in your family, it may benefit you to visit your doctor and get some more information on the matter. Don't leave it too long, the key to beating cancer is to treat it before it spreads too far.
A Short History of Cancer:
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