Benign breast conditions (also known as benign breast disease) are non-cancerous breast disorders. Some of these conditions increase the risk of breast cancer and others do not. When assessing breast cancer risk, these disorders are classified as either proliferative breast conditions (those with quickly growing cells) or non-proliferative breast conditions.
Proliferative breast conditions
Proliferative breast conditions have multiplying (proliferating) cells. Although they are not cancerous, they are linked to an increased risk of breast cancer [60-62]. The most common type of proliferative breast condition is hyperplasia. There are two types of hyperplasia: usual hyperplasia and atypical hyperplasia.
In usual hyperplasia, the proliferating cells look normal under a microscope. In atypical hyperplasia, the proliferating cells look abnormal. Women with atypical hyperplasia have about four times the breast cancer risk of women without a proliferative condition [60,61]. Women with usual hyperplasia have about two times the risk [60].
Non-proliferative breast conditions
Non-proliferative benign breast conditions—such as cysts—are not linked to breast cancer. Learn more about benign breast conditions.
Updated 11/09/09
