Table 5. Anatomic Stage/Prognostic Groupsa,b
| Stage | T | N | M |
| 0 | Tis | N0 | M0 |
| IA | T1b | N0 | M0 |
| IB | T0 | N1mi | M0 |
| T1b | N1mi | M0 |
| IIA | T0 | N1c | M0 |
| T1b | N1c | M0 |
| T2 | N0 | M0 |
| IIB | T2 | N1 | M0 |
| T3 | N0 | M0 |
| IIIA | T0 | N2 | M0 |
| T1b | N2 | M0 |
| T2 | N2 | M0 |
| T3 | N1 | M0 |
| T3 | N2 | M0 |
| IIIB | T4 | N0 | M0 |
| T4 | N1 | M0 |
| T4 | N2 | M0 |
| IIIC | Any T | N3 | M0 |
| IV | Any T | Any N | M1 |
| aReprinted with permission from AJCC: Breast. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 347-76. |
| bT1 includes T1mi. |
| cT0 and T1 tumors with nodal micrometastases only are excluded from Stage IIA and are classified Stage IB. |
| –M0 includes M0(i+). |
| –The designation pM0 is not valid; any M0 should be clinical. |
| –If a patient presents with M1 prior to neoadjuvant systemic therapy, the stage is considered Stage IV and remains Stage IV regardless of response to neoadjuvant therapy. |
| –Stage designation may be changed if postsurgical imaging studies reveal the presence of distant metastases, provided that the studies are carried out within 4 months of diagnosis in the absence of disease progression and provided that the patient has not received neoadjuvant therapy. |
| –Postneoadjuvant therapy is designated with "yc" or "yp" prefix. Of note, no stage group is assigned if there is a complete pathologic response (CR) to neoadjuvant therapy, for example, ypT0ypN0cM0. |
