Staging

Criteria for TNM Clinical Staging:

Physical examination; palpation of breast, axillary, supraclavicular and cervical nodes; pathologic examination of breast or other tissue to establish a diagnosis of cancer, including size of tumor, chest wall invasion, and presence or absence of positive nodes and distant metastases.

Removal of all primary tumor (no tumor at any margin of resection on gross examination) and at least Level I nodes (lateral to lateral border of pectoralis minor—at least 6 nodes in this area).

Brief Summaries of 6th Edition Categories
Tis	In situ
T1	2cm
T1mic	0.1 cm
T1a	> 0.1 to 0.5 cm
T1b	> 0.5 to 1 cm
T1c	>1 to 2 cm
T2	>2 to 5 cm
T3	> 5 cm
T4	Chest wall/skin
T4a	Chest wall
T4b	Skin edema/ulceration, satellite skin nodules
T4c	Both 4a and 4b
T4d	Inflammatory carcinoma
N1	Movable axillary pN1
N2	Fixed axillary
N3	Internal mammary
pN1a	Micrometastases only, # 0.2 cm
pN1b	Gross metastases i 1-3 nodes, >0.2 to < 2 cm ii 4 nodes/>0.2 to < 2 cm iii through capsule/ < 2 cm iv 2 cm

For more details on Collaborative Stage, see the Intro to Collaborative Staging module.