A diagnosis of cancer can be devastating. And there is good reason for this fear — Cancer is the second leading cause of death in the United States next to heart disease, and will claim more THAN HALF A MILLION LIVES THIS YEAR. CANCER ALSO KNOWN AS A MALIGNANT TUMOR OR MALIGNANT NEOPLASM, 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 new lump, abnormal bleeding, a prolonged cough, unexplained weight loss, and a change in bowel movements, among others. While these symptoms may indicate cancer they may also occur due to other issues. There are over 100 different known cancers that affect humans. Tobacco use is the cause of about 22% of cancer deaths. Another 10% is due to obesity, a poor diet, lack of physical activity, and drinking alcohol. Other factors include certain infections, exposure to ionizing radiation, and environmental pollutants. ] In the developing world nearly 20% of cancers are due to infections such as hepatitis B, hepatitis C, and human papillomavirus.
These factors act, at least partly, by changing the genes of a cell. Typically many such genetic changes are required before cancer develops. Approximately 5–10% of cancers are due to genetic defects inherited from a person’s parents. Cancer can be detected by certain signs and symptoms orscreening tests. 
It is then typically further investigated by medical imagingand confirmed by biopsy.  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, being vaccinated against certain infectious diseases, not eating too much red meat, and avoiding too much exposure to sunlight. 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. Pain and symptom management are an important part of care. Palliative care is particularly important in those with advanced disease. 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 survival rate in the developed world is on average 80%. For cancer in the United States the average five year survival rate is 66%. In 2012 about 14. 1 million new cases of cancer occurred globally (excluding skin cancer other than melanoma). It caused about 8. 2 million deaths or 14. 6% of all human deaths. The most common types of cancer in males are lung cancer,prostate cancer, colorectal cancer, and stomach cancer, and in females, the most common types are breast cancer, colorectal cancer, lung cancer, and cervical cancer.
If skin cancer other than melanoma were included in total new cancers each year it would account for around 40% of cases. In children acute lymphoblastic leukaemia and brain tumors are most common except in Africa where non-Hodgkin lymphoma occurs more often. In 2012 about 165,000 children less than 15 years of age were diagnosed with cancer. The risk of cancer increases significantly with age and many cancers occur more commonly in developed countries. Rates are increasing as more people live to an old age and as lifestyle changes occur in the developing world.
The financial costs of cancer have been estimated at $1.16 trillion US dollars per year as of 2010. The good news is that many forms of cancer can be avoided, and with early detection, a great number can be cured. In this article, we will look at the many faces of cancer so that you can understand the disease and its treatment, and also so that you learn about steps you can take to limit your exposure. What we think of as “cancer” is actually a group of more than one hundred separate diseases. These diseases are all characterized by an abnormal and unregulated growth of cells.
This growth destroys surrounding body tissues and may spread to other parts of the body in a process that is known as metastasis. You have probably heard of all of these different types of cancer: ?Skin cancer (squamous cell carcinoma and basal cell carcinoma being the most common) ?Lung cancer ?Brain cancer ?Breast cancer ?Prostate cancer ?Colon cancer ?Ovarian cancer ?Leukemia ?Lymphoma There are many others as well. Cancer can develop anywhere in the body, and at any age. Unlike infectious diseases such as AIDS, theflu (influenza), or tuberculosis, cancer is not contagious — cancer is usually caused by genetic damage that happens inside an individual cell.
Cells affected by cancer are called malignant cells. Malignant cells are different from normal cells in the body in that they divide (in most cases) much more rapidly than they should. This is important to know because many drugs used to fight cancer (antineoplastic or anticancer drugs) attack malignant cells during the active phase of cell division. You may know someone who has had cancer, and his or her hair fell out during treatment. That happened because the anticancer drug(s) affected the normal hair follicle cells, which divide rapidly, as well as the rapidly-dividing malignant cells.