Cancer is the disease that everyone fears and the 'C' word is one that is often spoken in hushed tones. And rightly so too as cancer is on the way to becoming the number one killer disease in the US (it's actually number two with heart diseases currently in that position). The idea of a mutation that spreads throughout your body is one that is highly disturbing to think about, and at the same time it is all the more scary as there is no sure fire way to prevent it and no way to anticipate it. Heart disease is in most cases a result of an already weakened heart, familial links, smoking, cholesterol etc; but in the majority of cancer cases despite some genetic links, it can strike at any time and without warning.
When we suffer from cancer this means that the DNA of a cell has become mutated and that means that when it splits via mitosis to create a new cell, that damaged DNA is then copied into the new cell – so that it spreads over time until whole areas become cancerous or a tumor forms. At the same time cancerous cells tend to reproduce more quickly than other cells as they have a shorter lifespan and that means that the cancer will quickly cause damage and grow out of control. If the cancerous cells are part of a major organ then eventually this organ will stop working and that can result in numerous complications and death. In other cases the cancer may spread to other areas and local structures (this is called metastasizing), which is why it's important for cancer to be detected early and then removed where possible.
However not all types of cancer are the same, and there are distinct differences between say brain cancer and liver cancer – partly because the cells themselves differ depending on where they are in the body and because the different organs perform different functions resulting in different dangers and symptoms. Some of these cancers are also more prevalent than others, while others are more dangerous. By understanding cancer and the different types of cancer, you can be more vigilant in catching it out before it takes a hold over your body and you can therefore help to protect yourself. Here we will look at the top five cancers to look out for – the top five killer cancers in America.
Lung cancer accounts for 28.3% of all cancer related deaths putting it as the number one killer cancer. Worldwide it is responsible for nearly 1.5 million deaths a year. It is of course characterized by cell growth in the lung tissues and the nearby tissue eventually. These forms of cancer are carcinomas which come from the epithelial cells.
Lung cancer can be seen on chest radiographs and computed tomography scans and is confirmed with biopsy. It is important for patients to look out for symptoms too which include shortness of breath, coughing up blood, chronic coughing, wheezing, chest pain, fatigue, weight loss, and difficulty swallowing. If you suffer any of these symptoms you should seek medical attention immediately.
Common treatments for lung cancer are surgery, radiotherapy and chemotherapy which aim to remove cancerous cells or prevent their proliferation. Surgery is more common in a type of lung cancer called 'non-small cell lung cancer' (NSCLC) as this form doesn't spread as early as other forms.
Of course the primary cause of lung cancer is smoking and this accounts for 15% of all cases of lung cancer. This is a quick way to demonstrate just how important it is to avoid tobacco smoke. On top of this exposure to asbestos, pollution and radon gas all make lung cancer more likely, while genetic factors may also play a role.
Colon cancer is colorectal cancer which takes place in the colon – the last part of the digestive system which is responsible for extracting water and salt from waste before elimination. Growths confined to the colon will usually be diagnosed through a colonoscopy and are often treatable. 90% of cases discovered at this stage will survive past five years. However if this spreads into the lymph nodes the prognosis becomes worse (48%) and if it spreads further it is largely untreatable and only 7% survive. It is the third most commonly diagnosed cancer in the world, and is found often in developing countries. In the US it is the second biggest cause of cancer related deaths and accounts for 9.6% of such fatalities.
The symptoms of colon cancer vary depending on where the tumor is located and are most pronounced when it is located nearer the anus. This will result in altered bowel habits – unexplained constipation, diarrhea, gastrointestinal bleeding, and the need to use the toilet that won't be satisfied. In some cases the tumor can be large enough to fill the entire lumen and in this case it can cause abdominal distension – a visible enlargement of the stomach. Eventually it may cause perforation and peritonitis. Alternatively colonic tumors located to the left that are large enough in size may cause 'hydronephrosis' or distension of the renal pelvis calyces and resulting in the atrophy of the kidney.
Colon cancer is most common in those in their 60s and 70s and cases before 50 are less common except where there is a family history. Smokers are also more likely again to develop colonic cancer, as are those who consume diets high in red meat and low in fruit, vegetables and poultry. Alcohol consumption is also a big risk factor. On the other hand exercise can reduce the chances of colonic cancer. Treatments are again often surgery or chemotherapy.
Breast cancer is a cancer with a lot of publicity and it is responsible for 7.4% of cancer related deaths. Of course this cancer affects the tissue of the breasts and is actually able to affect both men and women, though it is more likely to affect women. Most commonly the cancer will originate in the inner lining of the milk ducts or alternatively the lobules which supply those ducts with milk. Treatment is often surgical, though chemotherapy, hormonal therapy, radiation and immunotherapy are also used. Often surgery will be used to remove cancerous tissues and chemotherapy will then be used subsequently to prevent re-occurrence.
What's important to look out for with breast cancer is changes to the skin and texture of the breast. One of the most common symptoms is a lump which feels different from the rest of the breast and the discovery of a lump helps identify over 80% of cases. Other changes might include changes to the size, shape or texture of the breast or nipple. The appearance of small white spots may also be indicative. From here a mammogram will be used in order to diagnose the condition.
The main risk factor for breast cancer is of course female sex. However age also plays a role, while mothers who have had children and breast fed are less likely to develop breast cancer. Meanwhile smoking and drinking yet again can increase risk.
The pancreas is an endocrine gland responsible for the production of many hormones including insulin, glucagon and somatostatin and is also a digestive organ which helps to secrete important enzymes and assists the absorption of nutrients.
Pancreatic cancer is the fourth most common cause of cancer death in the US and across the rest of the world and accounts for 6% of such deaths. The condition has a poor prognosis when compared to other cancers at all stages and only 6% of cases survive past five years.
Part of the danger with pancreatic cancer is that it has few discernible symptoms which earn its name 'the silent killer'. Thus the condition is rarely diagnosed before it has reached the advanced stages.
Where there are symptoms they include loss of appetite, weight loss, jaundice (yellowing of the skin and eyes), pain in the abdomen, diabetes (due to the role of the pancreas in the production of insulin), depression due to hormonal changes and 'trousseau sign' where blood clots form in the portal blood vessel. The main risk factors are family history, as well as age – with most cases occurring past the age of sixty. Smoking and drinking also increases the likelihoods of developing the condition (though the latter is controversial), as will obesity or a diet high in red meat and low in fruits and vegetables. Soft drinks have also been implicated, and diabetics are more likely to suffer from it also.
Treatment again depends on the stage of the cancer as well as the type but most commonly involves the 'Whipple procedure' in which the pancreatic head and curve of the duodenum are removed surgically and a bypass is created between the stomach to the jejunum. This of course cannot be performed where the cancer has affected local structures and as a form of major surgery carries its own risks.
Prostate cancer causes 5.1% of cancer deaths and is of course cancer which develops in the prostate tissue. The prostate is the gland in the male reproductive system which secretes and stores alkaline fluid which is milky and white in appearance and gives semen its color and texture while also helping to expel it during ejaculation.
Prostate cancer is slow growing in most cases though in some cases may spread aggressively and increase the chances of metastasizing to other areas and particularly the bones and lymph nodes. Symptoms include pain, difficulty urinating, frequent urination, difficulty ejaculating, blood in the urine (hematuria), sexual problems, erectile dysfunction and other symptoms – though often these are not present until the later stages. Genetics, diet and other factors increase the risk of prostate cancer and it is usually confirmed through biopsy and CT scans.
The primary treatments for prostate cancer are surgery, radiation, radio surgery and proton therapy though chemotherapy and other methods may also be used.
Other Leading Killer Cancers
While these are the top five killer cancers, other leading causes of cancer related deaths are liver cancer (3%), ovarian cancer (2.7%), esophageal cancer (2.4%), bladder cancer (2.4%) and brain/meninges cancer (2.3%). These ten combined account for 69.1% of all cancer deaths.
What we can learn from these statistics is that cancer is a dangerous condition and one that we often can do little about; but that our lifestyle habits can affect our likelihood of developing the various kinds. Smoking is responsible for a huge proportion of cancers and drinking is also a large risk factor. By quitting these destructive habits and making sure to consume a healthy diet and get exercise you become far less likely to suffer. Meanwhile make sure to stay on the lookout, particularly for the symptoms of these top 5 killer cancers – because if you catch the problems early you will greatly increase your chances of survival.