Med Insider
Breast Cancer — The Basics
Updated: Jul 15, 2022
By Jessica Raju

Introduction
Breast cancer is cancer that forms in the cells of the breasts. After skin cancer, breast cancer is the most common cancer diagnosed in women in the United States. Breast cancer can occur in both men and women, but it's far more common in women.
About 1 in 8 U.S. women (about 13%) will develop invasive breast cancer over the course of their lifetime.
About 1 in 8 U.S. women (about 13%) will develop invasive breast cancer over the course of their lifetime.
About 2,650 new cases of invasive breast cancer are expected to be diagnosed in men in 2021. A man’s lifetime risk of breast cancer is about 1 in 833.
About 43,600 women in the U.S. are expected to die in 2021 from breast cancer. Death rates have been steady in women under 50 since 2007, but have continued to drop in women over 50. The overall death rate from breast cancer decreased by 1% per year from 2013 to 2018.

Signs of Breast Cancer
Signs of breast cancer are the first changes people themselves notice before consulting a specialist. Although, different people have different symptoms of breast cancer and some people do not have any signs or symptoms at all. The following are the most common signs of breast cancer:
Swelling under the armpit or collarbone
Swelling of the breast
Dimpling of the skin
Discharge from the nipple
Skin changes on the breast on nipple
Nipple that turns inwards
Risk Factors
Risk factors include:
Age
Genetics
A History of Breast cancer and breast lumps
Dense breast tissue
Estrogen exposure and breastfeeding
Body weight
Alcohol consumption
Radiation exposure
Hormone treatments

Conclusion
Although definite causes cannot be declared for breast cancer, researchers have identified hormonal, lifestyle, and environmental factors that may increase the risk of breast cancer. But it's not clear why some people who have no risk factors develop cancer, yet other people with risk factors never do. It's likely that breast cancer is caused by a complex interaction of genetic makeup and environment. Therefore the best course of action is to get regular screenings done to ensure nothing unusual and if someone notes something unusual, they should immediately go to the hospital.