The "T" stage is as follows:
For kidney (cortex) tumors:
• T1-tumor size of 7 cm or less and confined to the kidney
• T2-tumor size more than 7 cm, but still confined to the kidney
• T3a-tumor invading into the adrenal gland or just outside of the kidney
• T3b-tumor invading into the renal vein or inferior vena cava, but contained below the diaphragm
• T3c- tumor invading into the renal vein or inferior vena cava, but extending above the diaphragm
• T4-tumor invades outside of these areas
For collecting system tumors:
• T1-tumor contained within the collecting system
• T2-tumor invades into the muscular layer of the wall of the collecting system
• T3-tumor invades into the fat surrounding the collecting system
• T4-tumor invades into other organs
The "N" stage is as follows for any subsite:
• N0-no spread to lymph nodes
• N1-tumor spread to a single lymph node
• N2-tumor spread to multiple lymph nodes or for collecting system tumors, lymph node spread that is between 2 and 5 cm
• N3-for collecting system tumors only, those lymph nodes that are >5 cm
The "M" stage is as follows:
• M0-no tumor spread to other organs
• M1-tumor spread to other organs
The overall stage is based on a combination of these T, N, and M parameters:
For kidney cortex tumors
• Stage I: T1N0M0
• Stage II: T2N0M0
• Stage III:
o T1-2N1M0
o T3N0-1M0
• Stage IV: and T4, any N2 or M1
For collecting system tumors
• Stage I: T1N0M0
• Stage II: T2N0M0
• Stage III: T3N0M0
• Stage IV: any T4, any N1-3, any M1
