Answer the following question given this paragraph: 

Breast cancer is the most common type of cancer in females. It occurs when cells in the breast grow out of control and form a tumor. Breast cancer is rare in teens but becomes more common as females get older. Regular screening is recommended for most women starting around age 40. If found early, breast cancer usually can be cured with surgery.


Q: What disease occurs when cells in the breast grow out of control and form a tumor?


A:
breast cancer