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