Table 1 TNM Classification for anal cancer
From: Radiological assessment of anal cancer: an overview and update
Primary tumor (T) | |
TX | Primary tumor cannot be assessed |
T0 | No evidence of primary tumor |
Tis | Carcinoma in situ (Bowen disease, high-grade squamous intraepithelial lesion [HSIL], anal intraepithelial neoplasia II-III (AIN II-III) |
T1 | Tumor 2 cm or less in greatest dimension |
T2 | Tumor more than 2 cm but not more than 5 cm in greatest dimension |
T3 | Tumor more than 5 cm in greatest dimension |
T4 | Tumor of any size invades adjacent organ(s) (eg, vagina, urethra, bladder);direct invasion of the rectal wall, perirectal skin, subcutaneous tissue, or the sphincter muscle(s) is not classified as T4 |
Regional lymph nodes (N) | |
NX | Regional lymph nodes cannot be assessed |
N0 | No regional lymph node metastasis |
N1 | Metastasis in perirectal lymph node(s) |
N2 | Metastasis in unilateral internal iliac and/or inguinal lymph node(s) |
N3 | Metastasis in perirectal and inguinal lymph nodes and/or bilateral internal iliac and/or inguinal lymph nodes |
Distant metastasis (M) | |
M0 | No distant metastasis |
M1 | Distant metastasis |