Two Distinct Pathways to Development of Squamous Cell Carcinoma of the Vulva

Table 2

Classifications of vulvar intraepithelial neoplasia. (WHO, ISSVD, and Bethesda-like classifications are shown.)

	WHO (2003)
	VIN 1,2,3 (warty type/basaloid type)
	VIN 1,2,3 (simplex type)
	ISSVD (2004)∗
	VIN, usual type (VIN 2,3)
	(a) warty type
	(b) basaloid type
	(c) mixed type
	VIN 3, differentiated type (VIN 3)
	Bethesda-like system [6]
	Low-grade VIL (condyloma NIN 1)
	High-grade VIL (VIN 2/VIN 3)

∗VIN1: abolished terminology.