Meaning of stage IA breast cancer: Stage I breast cancer is divided into stages IA and IB.

Definition of stage IA breast cancer

Stage I breast cancer is divided into stages IA and IB. In stage IA, the tumor is 2 centimeters or smaller and has not spread outside the breast.

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.