Primary Tumor (T) | |
Regional Lymph Nodes (N) | |
Distant Metastasis (M) | |
Histologic Grade (G) | |
This view displays the TNM formula. Please select appropriate value from the list for T/N/M/G variables. The result will be displayed, based on your selection of variables.
Definition of Primary Tumor (T)
T Category | T Criteria |
---|---|
TX | Tumor cannot be assessed |
T0 | No evidence of primary tumor |
Tis | High-grade dysplasia, defined as malignant cells confined to the epithelium by the basement membrane |
T1 | Tumor invades the lamina propria, muscularis mucosae, or submucosa |
T1a | Tumor invades the lamina propria or muscularis mucosae |
T1b | Tumor invades the submucosa |
T2 | Tumor invades the muscularis propria |
T3 | Tumor invades adventitia |
T4 | Tumor invades adjacent structures |
T4a | Tumor invades the pleura, pericardium, azygos vein, diaphragm, or peritoneum |
T4b | Tumor invades other adjacent structures, such as the aorta, vertebral body, or airway |
Definition of Regional Lymph Node (N)
N Category | N Criteria |
---|---|
NX | Regional lymph nodes cannot be assessed |
N0 | No regional lymph node metastasis |
N1 | Metastasis in one or two regional lymph nodes |
N2 | Metastasis in three to six regional lymph nodes |
N3 | Metastasis in seven or more regional lymph nodes |
Definition of Distant Metastasis (M)
M Category | M Criteria |
---|---|
M0 | No distant metastasis |
M1 | Distant metastasis |
G | G Definition |
---|---|
GX | Grade cannot be assessed |
G1 | Well-differentiated adenocarcinoma. In these tumors, greater than 95% of the tumor is composed of well-formed gland s. |
G2 | Moderately differentiated adenocarcinoma. In these tumors, 50-95% of the tumor shows gland formation. Most adenocarcinomas are categorized as moderately differentiated tumors. |
G3 | Poorly differentiated adenocarcinoma. These tumors are composed predominantly of nests and sheets of neoplastic cells. Only less than 50% of the tumor shows gland formation. |
NA | Not Applicable |