Stage IIIB includes: (T1/T2, N2a/N2b, M0). T1: Invasive vulvar cancer confined to the vulva or perineum. T2: Vulvar cancer with tumor of any size with extension to adjacent perineal structures (lower/distal 1/3 urethra, lower/distal 1/3 vagina, anal involvement). N2a: Vulvar cancer with three or more lymph node metastases each measuring 5 mm or less. N2b: Vulvar cancer with two or more lymph node metastases measuring 5 mm or greater. M0: No distant metastasis. (AJCC 7th ed.) [from
NCI]