Stage (five-year survival)	Characteristics
I	Carcinoma strictly confined to the cervix (extension to the uterine corpus should be disregarded)
IA (93%)	Invasive cancer identified only microscopically; all gross lesions, even with superficial invasion, are stage IB cancers; invasion is limited to measured invasion of stroma ≤ 5 mm in depth and ≤ 7 mm in horizontal spread
IA1	Measured invasion of stroma ≤ 3 mm in depth and ≤ 7 mm in horizontal spread
IA2	Measured invasion of stroma > 3 mm to ≤ 5 mm in depth, and ≤ 7 mm in horizontal spread
IB (80%)	Clinical lesions confined to the cervix or microscopic lesions greater than IA2
IB1	Clinical lesion ≤ 4 cm in size
IB2	Clinical lesion > 4 cm in size
II	Carcinoma extends beyond uterus but not to pelvic wall or to lower one-third of the vagina
IIA (63%)	No parametrial invasion
IIA1	Clinical lesion ≤ 4 cm in size
IIA2	Clinical lesion > 4 cm in size
IIB (58%)	Parametrial invasion
III	Carcinoma extends to pelvic wall and/or involves the lower one-third of the vagina, and/or causes hydronephrosis or non-functioning kidney
IIIA (35%)	Involves lower one-third of the vagina, no extension to the pelvic wall
IIIB (32%)	Extends to pelvic wall and/or causes hydronephrosis or nonfunctioning kidney
IV	Carcinoma extends beyond the true pelvis or has clinically involved the mucosa of the bladder or rectum
IVA (16%)	Spread to adjacent organs
IVB (15%)	Spread to distant organs