Anal Cancer Staging 

Updated: Jan 04, 2017
  • Author: Jeffrey B VanDeusen, MD, PhD; Chief Editor: N Joseph Espat, MD, MS, FACS  more...
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TNM Classification for Anal Cancer

The American Joint Committee on Cancer (AJCC) tumor/node/metastasis (TNM) classification and staging system for anal cancer are provided below. [1, 2] Note that these are based on the AJCC Cancer Staging Manual, 7th Edition (2010). Although the 8th edition has been published, implementation of the new system has been delayed until January 1, 2018. The AJCC advises that, "All newly diagnosed cases through December 31st 2017 should be staged with the 7th edition." [3]

Table 1. TNM Classification for Anal Cancer (Open Table in a new window)

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

Table 2. Anatomic stage/prognostic group (Open Table in a new window)

Stage T N M
0 Tis N0 M0
I T1 N0 M0
II T2 N0 M0
T3 N0 M0
IIIA T1 N1 M0
T2 N1 M0
T3 N1 M0
T4 N0 M0
IIIB T4 N1 M0
Any T N2 M0
Any T N3 M0
IV Any T Any N M1