Staging is conceded to settle on the degree to which a tumor has spread inside the body. Staging of is carried out identically to the staging of . A system which is known as TNM takes into account the cancer size, lymph node connection by cancer, and existence of metastasis:

  • T: tumor size and amount of local spread
  • N: degree of tumor participation of lymph nodes in the axillary (underarm) area. Since the nipple area is rich in lymphatic vessels, male breast usually spreads via the lymphatic channels to the axillary lymph nodes. (When the tumor has spread to the lymph nodes, doctors occasionally use the term “lymph node-positive” tumor.)
  • M: existence of remote metastases

Stage 0

Stage 0 refers to intraductal carcinoma, in which the growth cells have not multiplied outside the boundaries of the ducts themselves.

Stage I

In Stage I of male breast cancer, the lump is 2 cm or less in utmost diameter and has not multiplied to the lymph nodes or to other sites in the body.

Stage II

Stage II cancers are alienated into two groups. Stage IIA cancer is either less than 2 cm in width with  being  spread to the axillary lymph nodes, or the lump is between 2 cm-5 cm but has not spread to the axillary lymph nodes. Stage IIB tumors are either larger than 5 cm without being spread to the lymph nodes or are between 2 cm-5 cm in size and have reached the axillary lymph nodes.

Stage III

Stage III is measured to be locally complex tumor. Stage IIIA means the tumor is lesser than 5 cm but has spread to the axillary lymph nodes, and the axillary lymph nodes are connected to each other or to other structures; or the lump is greater than 5 cm in width with being spread to the axillary lymph nodes, which may be connected to each other or to other structures. Stage IIIB tumors have spread to neighboring tissues such as , chest wall, and ribs, or to the lymph nodes within the chest wall.

Stage IV

Stage IV cancer refers to metastatic malignancy, meaning it has spread to other parts of the body. With breast disease, metastases (sites of lump elsewhere in the body) are most often found in the , , liver, or . Stage IV tumor is also diagnosed when the tumor can be located in the lymph nodes of the .