Kidney Cancer is most often staged using the The American Joint Committee on Cancer (AJCC) staging system. To determine your AJCC kidney cancer stage, you first need to know three pieces of information about your disease (this is referred to as the TNM system):
PT or T refers to the size of the primary tumor; it may be abbreviated as PT or T;
N refers to whether the cancer has spread to nearby lymph nodes; and
M tells you whether the cancer has spread or metastisized to distant organs.
T1a: the tumor is no greater than 4 cm (about 1½ inches) across or smaller and is only in the kidney.
T1b: the tumor is larger than 4 cm but not larger than 7 cm across and is only in the kidney.
T2a: the tumor is more than 7 cm (about 3 inches) but not more than 10 cm and is only in the kidney.
T2b: the tumor is more than 10 cm (about 4 inches) across and is only in the kidney.
T3a: the tumor (regardless of size) is growing into the branches of the main renal vein leading out of the kidney or into fatty tissue in and around the kidney.
T3b: the tumor (regardless of size) is growing into the renal vein or is growing into the vena cava (large vein leading into the heart) but has not extended into the chest.
T3c: the tumor (regardless of size) has grown into the vena cava and has extended into the chest.
T4: the tumor has grown beyond the fibrous layer that surrounds the kidney and is extending into adjacent organs, such as the liver, spleen, pancreas or intestines.
Nx: regional (nearby) lymph nodes cannot be assessed by pathologist because lymph nodes weren't present or resected during surgery.
N0: regional lymph nodes were resected but were found to be free of disease.
N1: regional lymph nodes were positive for cancer.
M0: There is no spread to distant lymph nodes or other organs.
M1: Distant metastasis is present; includes spread to distant lymph nodes and/or to other organs. Kidney cancer most often spreads to the lungs, bones, liver, or brain.
Once doctors are able to establish your T, N and M status, usually done following surgery, you can determine your AJCC stage described in the table below.
T1, N0, M0
The tumor is smaller than 7 cm and has not spread outside the kidney or to nearby lymph nodes.
T2, N0, M0
The tumor is larger than 7 cm and has not spread outside the kidney or to nearby lymph nodes.
T3 or T1-T3, N1, M0
The tumor is locally advanced and is either T3a, T3b or T3c but still M0 OR the tumor is any size without having grown beyond the kidney and there is spread to regional lymph nodes.