8th edition TNM anal cancer staging

Stage I T1 – tumor not more than 2 cm in greatest dimension
N0 – no regional lymph nodes
M0 – no distant metastases
Stage IIa T2 – tumor more than 2 cm but not more than 5 cm in greatest dimension
N0 – no regional lymph nodes
M0 – no distant metastases
Stage IIbT3 – tumor more than 5 cm in greatest dimension
N0 – no regional lymph nodes
M0 – no distant metastases
Stage IIIaT1 or T2
N1 – metastasis in regional lymph nodes
N1a – inguinal, mesolectal and or internal iliac nodes
N1b – external iliac nodes
N1c – external iliac, inguinal, mesolectal and or internal iliac nodes
M0 – no distant metastases
Stage IIIbT4 – tumor of any size invades adjacent organs (vagina, urethra, bladder); direct invasion of rectal wall, perirectal skin, subcutaneous tissues or sphincter muscles is not considered as T4
N0 – no regional lymph nodes
M0 – no distant metastases
Stage IIIcT3 
N1 – metastasis in regional lymph nodes 
M0 – no distant metastases
Stage IVAny T
Any N
M1 – distant metastases