Table 1.

Staging systems of urachal carcinoma

	Stage	Sheldon staging system [2]		Mayo staging system [2]	TNM staging system
Localized disease	I	Tumor is limited to the urachal mucosa		Tumor is confined to the urachus and/or bladder	T1	Tumor invades the subepithelial connective tissue
	II	Invasion confined to the urachus itself (not beyond muscle layer)		Extension beyond the muscular layer of the urachus and/or bladder	T2	Invasion of the muscular layer of the urachus or bladder
Locally advanced disease	III	IIIA	Local extension to the bladder	Metastasis to regional lymph nodes	T3	Invasion of the perivisceral soft tissue, prostate, uterus, or vagina
		IIIB	Local extension to abdominal wall
		IIIC	Invasion of the peritoneum
		IIID	Invasion of the local viscera other than the bladder
Advanced disease	IV	IVA	Metastasis to lymph nodes	Metastasis to nonregional lymph nodes or other distant sites	T4	Invasion of the abdominal wall and metastasis to lymph nodes or other distant sites
		IVB	Distant metastasis

TNM = tumor, node, metastasis.