Last Modified: 02/15/2013
Stage Information for Anal Cancer
The anal canal extends from the rectum to the perianal skin and is lined by a mucous membrane that covers the internal sphincter. The following is a staging system for anal canal cancer that has been described by the American Joint Committee on Cancer (AJCC) and the International Union Against Cancer.[1] Tumors of the anal margin (below the anal verge and involving the perianal hair-bearing skin) are classified with skin tumors.
Definitions of TNMThe following is a staging system for anal canal cancer that has been described by the AJCC and the International Union Against Cancer.[1]
Table 1. Primary Tumor (T)a| TX | Primary tumor cannot be assessed. |
| T0 | No evidence of primary tumor. |
| Tis | Carcinoma in situ (i.e., Bowen disease, high-grade squamous intraepithelial lesion, and anal intraepithelial neoplasia II–III.) |
| T1 | Tumor ≤2 cm in greatest dimension. |
| T2 | Tumor >2 cm but ≤5 cm in greatest dimension. |
| T3 | Tumor >5 cm in greatest dimension. |
| T4 | Tumor of any size invades adjacent organ(s), e.g., vagina, urethra, and bladder.b |
| aReprinted with permission from AJCC: Anus. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 165-73. | |
| bDirect invasion of the rectal wall, perirectal skin, subcutaneous tissue, or the sphincter muscle(s) is not classified as T4. |
Table 2. Regional Lymph Nodes (N)a
| aReprinted with permission from AJCC: Anus. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 165-73. | |
| NX | Regional lymph nodes cannot be assessed. |
| N0 | No regional lymph node metastasis. |
| N1 | Metastases in perirectal lymph node(s). |
| N2 | Metastases in unilateral internal iliac and/or inguinal lymph node(s). |
| N3 | Metastases in perirectal and inguinal lymph nodes and/or bilateral internal iliac and/or inguinal lymph nodes. |
Table 3. Distant Metastasis (M)a
| aReprinted with permission from AJCC: Anus. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 165-73. | |
| M0 | No distant metastasis. |
| M1 | Distant metastasis. |
Table 4. Anatomic Stage/Prognostic Groupsa
| Stage | T | N | M |
| aReprinted with permission from AJCC: Anus. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 165-73. | |||
| 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 |
References
- Anus. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 167-169.