Flow cytometric DNA analysis of extramammary Paget's disease of the vulva

Vulvar extramammary Paget's disease (EMPD) is an uncommon disease entity that occurs predominantly in postmenopausal white women. The clinical behavior of this neoplasm is extremely variable, reflecting the various histological patterns that have been reported with this lesion. Flow cytometry has been used as a method of obtaining prognostic information about a number of gynecological neoplasms, yet to date there have been no flow cytometric studies performed on this unusual neoplasm. We performed flow cytometric analysis of 14 cases of paraffin-embedded vulvar EMPD in patients ranging from 45 to 86 years of age. We correlated histological features and clinical recurrence risk with DNA analysis. Although we were unable to show a statistically significant correlation between DNA ploidy or S-phase and time to recurrence, we did show a statistically significant correlation between DNA ploidy and histological features. Aneuploidy appears to be associated with in situ sweat gland adenocarcinoma, invasive carcinoma, and lymphatic invasion. These results suggest that Paget's cells with aneuploid DNA stem lines may be associated with the potential for aggressive biologic behavior.