Stage	Characteristics
I	The carcinoma is strictly confined to the cervix (extension to the corpus should be disregarded).
IA	Invasive cancer identified only microscopically. All gross lesions, even with superficial invasion, are Stage IB cancers. Invasion is limited to a measured stromal invasion with a maximal depth of 5.0 mm and a horizontal extension of ≤ 7.0 mm. Depth of invasion should be ≤ 5.0 mm taken from the base of the epithelium, either surface or glandular, from which it originates. Vascular space involvement, either venous or lymphatic, should not alter the staging.
IA1	Measured stromal invasion of ≤ 3.0 mm in depth and extension of ≤ 7.0 mm.
IA2	Measured stromal invasion of > 3.0 mm and ≤ 5.0 mm in depth with an extension of ≤ 7.0 mm
IB	Clinical lesions confined to the cervix or preclinical lesions > IA. All gross lesions even with superficial invasion are Stage IB cancers
IB1	Clinical lesions ≤ 4 cm in size.
IB2	Clinical lesions > 4 cm in size.
II	The carcinoma extends beyond the cervix, but has not extended onto the pelvic wall; the carcinoma involves the vagina, but not as far as the lower third.
IIA	No obvious parametrial involvement. Involvement of up to the upper two‐thirds of the vagina.
IIB	Obvious parametrial involvement, but not into the pelvic sidewall.
III	The carcinoma has extended onto the pelvic wall; on rectal examination there is no cancer‐free space between the tumour and the pelvic wall; the tumour involves the lower third of the vagina; all cases with a hydronephrosis or non‐functioning kidney should be included, unless they are known to be due to other causes.
IIIA	No extension onto the pelvic wall, but involvement of the lower third of the vagina.
IIIB	Extension onto the pelvic wall or hydronephrosis or non‐functioning kidney.
IV	The carcinoma has extended beyond the true pelvis or has clinically involved the mucosa of the bladder or rectum.
IVA	Spread of the growth to adjacent organs.
IVB	Spread to distant organs.