There were 14.1 million adults diagnosed with cancer in 2012. More than 8 million died of cancer in the same year, accounting for 14.6 percent of all human deaths worldwide. A lot of people are dying from cancer every day. From the more popular leukemia to the lesser known mesothelioma, here are the 8 deadliest cancers in human history.
1. Lung cancer
This deadly disease is characterized by the growth of one or more malignant tumors within the lung tissue. If you think leaving it alone will make you better, you are dead wrong. It has been known to spread to nearby tissues and other places of the body when left untreated – a condition known as metastasis. Also known as pulmonary carcinoma and carcinoma of the lung, it was attributed to 1.56 million deaths in 2012. When it comes to cancers, this is the deadliest in both men and women worldwide.
Most symptoms of lung cancer are not specific. That is, they do not give a clear indication that the lungs are affected. As a result, majority of lung cancer patients find out too late. By then, the cancerous growth has spread from the original site to distant areas of the body. Only 16.8 percent of people diagnosed with lung cancer in the United States make the 5-year survival mark. The numbers are far grave in other parts of the world.
Who’s at risk? Prolonged exposure to tobacco smoke is the leading cause of lung cancers – around 80 to 90 percent of the time. But even non-smokers have a 10 to 15 percent chance of acquiring pulmonary carcinoma, possibly due to the combination of hereditary factors and exposure to lung irritants, secondhand smoke, and air pollution.