Benign is the opposite of malignant, which means that a particular growth or a change in the body is not cancerous. Often, people who are diagnosed with tumors or extra growths are tested for cancer, and when this test turns out to be negative, then that growth is called as a benign tumor or growth. A tumor is an abnormal growth that happens in the cells of the body in specific parts such as the brain, respiratory tract, intestines, reproductive organs, and others. When this process goes out of control and spreads to the entire body it is called metastasis (See: Metastasis) and turns cancerous. However, if the tumor is only localized and does not spread to other parts of the body then it is called benign. In most cases, these benign tumors can be excised by surgery. This is done when they accumulate mass and grow large. In such cases, they tend to pressurize the surrounding tissues and damage them. However, benign tumors might normally be asymptomatic and might cause symptoms only after they gain a particular mass depending upon their location. Tumors of the insulin (insulinoma) and pituitary glands (pituitary adenomas) can cause dangerous conditions by excess secretion of the hormones.