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Cancer is caused by a succession of gene mutations that accumulate after many years, some factors can increase the rate at which genetic mutations occur and increase the risk of cancer. Smoking tobacco, drinking alcohol, sedentary lifestyle and obesity. As age increases, cancer risk also increase. Age increases mutations and the risk of cancer.
Thymus gland is an organ of the immune system, it nurtures and develops T cells which are major components in the immune system. Decline in the immune system’s strength is caused by steady deterioration of thymus. The thymus begins to shrink from the age 1. It reduces into halve at age 16, this also affects the T cells.
Cancer cells are continually arising in the body but the immune system kills them before a new tumor is made. The T cells are always scanning for cancer cells and destroying them. Age-related cancer risk increases more in men compared with women because the thymus declines more rapidly in men than women.
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