# Anal cancer staging (AJCC chapter 21)

Source: https://onco.cc/terms/anus-staging/  
OnCo record `anus-staging` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Anal cancer is staged by tumour size (2 cm and 5 cm are the cut-offs), spread to nearby organs or lymph nodes in the pelvis and groin, and distant spread as stage IV.

## Summary

AJCC chapter 21 covers the anus; the AJCC 2026 table lists a Version 9 protocol for 2023. In the NCI's summary, stage 0 is abnormal cells in the mucosa; stage I is a tumour of 2 cm or less; IIA is 2 to 5 cm and IIB larger than 5 cm; IIIA is 5 cm or less with spread to nodes near the anus or groin; IIIB is any size with spread to nearby organs such as the vagina, urethra or bladder; IIIC combines local spread and nodes; stage IV is distant spread.

## Fields

- Kind: Term
- Last checked: 2026-11-04
- Also known as: anal cancer staging; anal cancer stage

## Sources

- National Cancer Institute, Anal cancer stages: https://www.cancer.gov/types/anal/stages
- American College of Surgeons, AJCC Current Staging System 2026 (which chapters are 8th edition and which Version 9): https://www.facs.org/media/c5ik5tkr/ajcc-current-staging-system-2026.pdf

## Connected records

- terms: [AJCC Version 9 staging](https://onco.cc/terms/ajcc-version-9/), [Disease-specific staging and risk systems (FIGO, Ann Arbor, IPI, R-ISS, ELN, IMDC)](https://onco.cc/terms/staging-systems/), [TNM staging](https://onco.cc/terms/tnm-staging/)
- cancers: [Anal cancer (squamous cell carcinoma)](https://onco.cc/cancers/anal/)

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JSON: https://onco.cc/api/v1/entities/anus-staging.json