The researchers are doing this study to see if giving people fluorescein sodium as an IV infusion before their vulvectomy for treating extramammary Paget's disease (EMPD) can help surgeons with performing the procedure. The researchers will look at whether fluorescein sodium helps surgeons identify disease cells that should be removed. Other purposes of this study include looking at the following: If there are any complications during or after vulvectomy involving the use of fluorescein sodium. If fluorescein sodium can reveal tissue that surgeons cannot operate on (unresectable tissue).

Inclusion Criteria:

• Age ≥18 years
• Noninvasive or microinvasive EMPD with a contiguous visible clinical lesion
• Newly diagnosed or recurrent lesion
• Scheduled to undergo wide local excision or vulvectomy not requiring resection of the clitoris, urethra, or anus and with the surgeon's judgment that primary closure is possible (V-Y advancement flap closure is allowed)

Exclusion Criteria:

• History of allergic reaction to fluorescein sodium
• Multifocal, noncontiguous clinical lesion
• Current or previous invasive EMPD
• History of invasive vulvar, vaginal, or anal cancer
• Lesion in which resection of the clitoris, urethra, and/or anus is deemed to be necessary
• Lesion in which a primary closure or V-Y advancement flap is believed not to be possible and a larger myocutaneous flap is needed for closure of the defect
• History of radiation therapy to the vulva and/or anus

People Undergoing Vulvectomy for Extramammary Paget's Disease (EMPD)

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