Cancer is not a single disease but a group of diseases, resulting from the presence and uninhibited growth of abnormal cells in our body. These may be present anywhere. These abnormal cells, together, form a tumour. Tumours that are dormant and do not spread are seldom dangerous. However, once the abnormal cells start invading neighboring cells, they are considered to be malignant tumours. These malignant tumours are the cause for cancer, one of the deadliest groups of diseases in the world. However, Medicine has made much progress and now, through early detection, we are able to control the effect, if not cure the cancer altogether.
Information about cancer
Cancer refers to any one of a large number of diseases characterized by the development of abnormal cells that divide uncontrollably and have the ability to infiltrate and destroy normal body tissue.
What’s in a name? Here, there’s everything! Cancers are named on the basis of their point of origin. Thus a cancer originating in the lung would be called Lung Cancer. If a cancer cell has originated in the lung and then spread to the liver (through metastases), it is called (Primary) Lung Cancer as the cancer cells formed in the liver through metastases are similar to the lung cancer cells. The treatment of the cancerous cells in the liver in this case will be the same as that for the primary lung cancer because cancer cells divide to form the exact same duplicate of themselves.
All it takes is one. One cell, that is. One abnormal cell can give rise to several others. But it's not as easy as it sounds. The very transformation of a normal cell into a cancerous one is a multi-stage process which usually involves a progression from a pre-cancerous lesion to a malignant tumour. These changes are the culmination of the mixing of a person's genetics and 3 categories of external agents:
- Physical carcinogens, such as asbestos, ultraviolet and ionizing radiation;
- Chemical carcinogens (components of tobacco smoke, aflatoxin – food contaminant, arsenic – drinking water contaminant)
- Biological carcinogens, such as infections from certain viruses, bacteria or parasites.
- For more "agents of cancer", you may refer to studies by WHO, which maintains a classification of cancer-causing agents.
Incidence of cancer has been shown to increase progressively with age. This has been thought to be associated with three factors:
- Possibly because of prolonged exposure to carcinogens
- Age-related progressive changes in the internal surroundings of the organism, which may create an increasingly favourable environment either for induction of new type of cancers or by promoting growth of already existing, but as yet latent, malignant cells and
- The third hypothesis is a combination of the above two hypothesis.
Knowledge is power. We know the causes and are aware of the means to prevent and control the spread of Cancer. Through the implementation of evidence-based strategies for cancer prevention, early detection of cancer and management of patients with cancer, we can change millions of lives. Contrary to popular belief, many cancers have a high chance of being cured if detected early and treated adequately.
More than 30% of cancer deaths can be prevented by avoiding or reducing the following:
- Tobacco consumption – causes approximately 20% of cancer deaths worldwide, of which 70% are caused by lung cancer.
- Hepatitis B Viral infection – Get an immunization.
- Exposure to ionizing and non-ionizing radiation – reduce exposure as much as possible
- Air pollution
- Unhealthy diet
- Physical inactivity
- Alcohol consumption
- Sexually-transmitted HPV-infection
- Avoid the risk factors
- Get a vaccine for Human Papilloma Virus (HPV) and hepatitis B virus (HBV).
- Control occupational hazards.
- Reduce exposure to non-ionizing radiation by sunlight. (UV)
- Reduce exposure to ionizing radiation (occupational or medical diagnostic imaging).
Early detection and prevention can save lives. There are two means to this end:
This refers to getting yourself checked on a regular basis to see if something is amiss, so that early diagnosis can determine the treatment and increase the chances of curing the cancer. Early diagnosis is relevant when there is no effective screening method.
This helps identify individuals with symptoms that may be suggestive of a specific cancer or pre-cancer. These individuals are then referred for treatment. This method is quite effective for cancer types that occur frequently. Due to the frequency of such types, the screening test facilities are also affordable, accessible and cost-effective.
Signs: Something that is visible to another person. Examples: Fever, heavy breathing etc.
Symptoms: A signal that's felt or noticed by the person who has it, but may not be easily seen by anyone else. Examples: Fatigue, weakness and so on.
How are signs and symptoms helpful?
The earlier the cancer is detected, the higher the chance of cure. Signs and symptoms are one of the ways to diagnose the cancer at an early stage. However, most people tend to ignore certain symptoms, dismissing them as, say, a normal cyst or an extended cough! These symptoms are not always caused by cancer, but it's important to have them checked out, just in case.
If left undiagnosed and, hence, untreated, it can prove to be an expensive affair, if not fatal. So economise and save your life. Get checked! Remember, delaying diagnosis does not change the diagnosis of the disease but results only in increasing the severity of the disease, making it difficult to treat.
Cancer: Signs and Symptoms
Different types of cancer have different kinds of signs and symptoms. These are also dependent on its location, its size and its extent of effect on organs and tissues. If a cancer has spread (metastasized), signs or symptoms may appear in different parts of the body.
Sometimes, the symptoms are noticeable. At other times, the cancer starts in places where it won't cause any signs or symptoms until it has grown quite large. Sometimes, cancer cells cause symptoms that are not usually linked to cancer! Talk about a master of disguise.
These are some of the general tell-tale signals of cancer. However, if you have any of these, relax. It may not always lead to cancer. It could just be something else, which is easier to cure.
NOTE: If any of these symptoms last for a long time or get worse, please see a doctor.
- Unexplained weight loss
- Fever - Usually occurs once the cancer has spread from its original location.
- Fatigue - As a cancer grows, this proves to be an important symptom. However, it appears early in some cases like leukaemia. Blood loss due to stomach or colon cancers can also cause fatigue.
- Pain - Pain due to cancer usually signifies that the cancer has spread from the origin to other parts of the body.However, it may be an early symptom for some cancers like bone cancer. A headache that does not go away or get better with treatment may be a symptom of a brain tumor.
- Skin changes - Though skin cancers cause a visible change, there are some other types that affect the skin as well. Some of the signs and symptoms are:
- Darker looking skin (hyperpigmentation)
- Yellowish skin and eyes (jaundice)
- Reddened skin (erythema)
- Itching (pruritis)
- Excessive hair growth
Change in bowel habits or bladder function - Long-term constipation, diarrhoea, or a change in the size of the stool may be a sign of colon cancer. Change in bladder function could be related to bladder or prostate cancer.
Sores that do not heal – These are indicative of different cancers depending on their location.Skin cancers may bleed and look like sores that don’t heal. A long-lasting sore in the mouth could be an oral cancer. Any sore that does not heal could be an indication of cancer. Please get it checked.
White patches inside the mouth or white spots on the tongue – Indicative of leukoplakia, a pre-cancerous area that’s caused by frequent irritation. This can become mouth cancer, if left untreated.
Unusual bleeding or discharge – This may be indicative of different cancers, depending on the mode of discharge.Coughing up blood could be symptomatic of lung cancer, while blood in the stool could be a sign of colon or rectal cancer.
Thickening or lump in the breast or other parts of the body –Many cancers can be felt through the skin. A lump or thickening of the skin is a symptom of cancer. These cancers occur mostly in the breast, testicle, lymph nodes (glands), and the soft tissues of the body. However, sometimes, breast cancers show up as red or thickened skin rather than a lump.
Indigestion or trouble swallowing – Usually indicative of cancer of the oesophagus.
Recent change in a wart or mole or any new skin change – A change in shape, size or colour of a mole, freckle or wart should not be ignored.See a doctor right away. A skin change may be a melanoma which, if found early, can be treated successfully.
Nagging cough or hoarseness – If it does not go away, it could be a sign of lung cancer, larynx cancer or thyroid cancer.
The signs and symptoms listed above are the more common ones seen with cancer, but there are many others that are not listed here. If you notice any major changes in the way your body works or the way you feel – especially if it lasts for a long time or gets worse – let a doctor know. If it has nothing to do with cancer, the doctor can find out more about what’s going on and, if needed, treat it. If it is cancer, you’ll give yourself the chance to have it treated early, when treatment works best.
10 Facts About Cancer
- There are more than 100 types of cancers; any part of the body can be affected.
- Cancers of major public health relevance such as breast, cervical and colorectal cancer can be cured if detected early and treated adequately.
- One fifth of all cancers worldwide are caused by a chronic infection, for example human papillomavirus (HPV) causes cervical cancer and hepatitis B virus (HBV) causes liver cancer.
- In 2012, there were an estimated 14.1 million new cases of cancer in the world: 7.4 million (53%) in males and 6.7 million (47%) in females, giving a male:female ratio of 10:9
- All patients in need of pain relief could be helped if current knowledge about pain control and palliative care were applied.
- Worldwide, the 5 most common types of cancer that kill men are (in order of frequency): lung, stomach, liver, colorectal and oesophagus.
- Worldwide, the 5 most common types of cancer that kill women are (in the order of frequency): breast, lung, stomach, colorectal and cervical. In many developing countries, cervical cancer is the most common cancer.
- More than 30% of cancer could be prevented, mainly by not using tobacco, having a healthy diet, being physically active and moderating the use of alcohol. In developing countries up to 20% of cancer deaths could be prevented by immunization against the infection of HBV and HPV
- Tobacco use is the single largest preventable cause of cancer in the world causing 22% of cancer deaths.
- About 70% of all cancer deaths occur in low- and middle-income countries.
The 10 Most Commonly Diagnosed Cancers in the World
Cancer is a leading cause of death worldwide, accounting for 8.2 million deaths in 2012.
The most common causes of cancer death are cancers of:
- Adrenal Cancer
- Bile Duct Cancer
- Bladder Cancer
- Bone Cancer
- Brain Cancer (Adult)
- Brain Cancer (Child)
- Breast Cancer
- Cancer in Children
- Colon Cancer
- Eye Cancer
- Endometrial Cancer
- Kidney Cancer
- Liver Cancer
- Leukaemia Cancer
- Lung Cancer
- Lung carcinoid tumour
- Lymphoma of the skin
- Melanoma Skin Cancer
- Non-small cell lung Cancer
- Oesophagus Cancer
- Oral Cancer
- Ovarian Cancer
- Pancreatic Cancer
- Penile Cancer
- Prostate Cancer
- Sinus Cancer
- Skin Cancer
- Stomach Cancer
- Throat Cancer
- Thyroid Cancer
- Uterine Cancer
- Retinoblastoma Cancer
- Testicular Cancer