Table 1.

Definition of Staging by SEER

Stage	Definition
Localized Disease	Incidental finding of malignancy in hemorrhoids, invasive intraluminal extension of tumor confined to the layers of the mucosa, and localized NOS.
Regional Disease	Direct extension or nodal involvement; includes extension to ischiorectal fat, perianal skin, perineum, pelvic floor muscles and anorectal sphincters, and vulva, and/or anorectal hemorrhoidal, hypogastric, lateral sacral, perirectal, and superficial inguinal nodes.
Distant Disease	Involvement of distant lymph node and extension to bladder, broad ligaments, cervix uteri, corpus uteri, pelvic peritoneum, prostate, urethra, vagina, and metastasis.