Cancer
is a leading cause of death worldwide, accounting for 8.2 million deaths in
2012. It is expected that annual cancer cases will rise from 14 million
in 2012 to 22 within the next 2 decades.
Definition
Cancer is a generic term for a
large group of diseases that can affect any part of the body. Other terms used
are malignant tumors and neoplasms. One of definition stated that cancer is the
rapid creation of abnormal cells that grow beyond their usual boundaries, and
which can then invade adjoining parts of the body and spread to other organs, and
the latter process is referred to as metastasizing. Metastases are the major
cause of death from cancer disease.
Key Facts
- Among male, the five most common sites of cancer diagnosed in 2012 were lung, prostate, colorectum, stomach, and liver cancer.
- Among female the five most common sites diagnosed were breast, colorectum, lung, cervix, and stomach cancer.
- About 30% of cancer deaths are due to the five leading behavioral and dietary risks: high body mass index, low fruit and vegetable intake, lack of physical activity, tobacco use, alcohol use.
·
Tobacco use is the
most important risk factor for cancer causing over 20% of global cancer deaths
and about 70% of global lung cancer deaths.
Cause of Cancer?
At the
beginning, cancer arises from one normal single cell. The transformation from a
normal cell into a tumor cell is a multistage process, typically a progression
from a pre-cancerous lesion to malignant tumors. These changes are the result
of the interaction between a person's genetic factors and three categories of
external agents, including:
- physical carcinogens, such as ultraviolet and ionizing radiation;
- chemical carcinogens, such as asbestos, components of tobacco smoke, aflatoxin (a food contaminant) and arsenic (a drinking water contaminant); and
- biological carcinogens, such as infections from certain viruses, bacteria or parasites
Reduce the risk of Cancer?
