INTRODUCTION
Extramammary Paget’s Disease (EMPD) is a rare malignancy that commonly presents on apocrine-rich skin as a unilateral scaly patch or plaque that often grows slowly and asymmetrically.1 There is growing evidence to suggest that Mohs micrographic surgery (MMS) may provide better patient outcomes and lower recurrence rates compared to wide local excision. We present a rare case of EMPD presenting as bilateral scrotal patches that were found via cytokeratin-7 (CK7) staining during MMS to connect subclinically in a contiguous fashion around the base of the penis.
CASE REPORT
A 60-year-old man from South Korea was referred for MMS with CK7 for biopsy-proven EMPD on the right and left scrotum. He was scheduled for wide local excision in South Korea prior to referral. His physician learned about the Mohs technique and the improved cure rates and made arrangements for referral and transfer of care. Physical examination revealed a 5.5 cm x 5 cm pink patch with features of EMPD on the left scrotum (Figure 1), and a 7 cm x 5 cm subtle pink and dyspigmented patch on the right scrotum (Figure 2).
During the preoperative consultation, scouting biopsies with CK7 staining were performed on each side, at 12, 3, 6, and 9 o’clock positions beyond the visible margins of the tumor to better assess the extension of EMPD (Figure 3). On the day of surgery, peripheral Mohs technique was used to remove a ring of tissue beyond the visible border and the positive scouting biopsies.2 MMS using CK7 staining was performed to improve accuracy of margin control, as highlighted in several recent studies.2-4
MMS required two days and five stages at which point the defects on the left and right scrotum were essentially contiguous in the suprapubic region and perineum. A small finger-like projection of EMPD was still positive in the inferior perineum. The patient refused to proceed with additional stages of Mohs in the office. The collaborating plastic surgeon removed the islands of tumor left in the center of the wound after peripheral margins were cleared. He also excised the positive area in the inferior perineum; en face processing with CK7 revealed cleared margins. The large contiguous defect on the right and left scrotum, which collided in the suprapubic region and below the scrotum, was repaired with a large, meshed skin graft (Figure 3).
During the preoperative consultation, scouting biopsies with CK7 staining were performed on each side, at 12, 3, 6, and 9 o’clock positions beyond the visible margins of the tumor to better assess the extension of EMPD (Figure 3). On the day of surgery, peripheral Mohs technique was used to remove a ring of tissue beyond the visible border and the positive scouting biopsies.2 MMS using CK7 staining was performed to improve accuracy of margin control, as highlighted in several recent studies.2-4
MMS required two days and five stages at which point the defects on the left and right scrotum were essentially contiguous in the suprapubic region and perineum. A small finger-like projection of EMPD was still positive in the inferior perineum. The patient refused to proceed with additional stages of Mohs in the office. The collaborating plastic surgeon removed the islands of tumor left in the center of the wound after peripheral margins were cleared. He also excised the positive area in the inferior perineum; en face processing with CK7 revealed cleared margins. The large contiguous defect on the right and left scrotum, which collided in the suprapubic region and below the scrotum, was repaired with a large, meshed skin graft (Figure 3).
DISCUSSION
EMPD often presents similar to an inflammatory skin condition, resulting in misdiagnosis and delayed treatment. Primary EMPD arises as an intraepidermal neoplasm of glandular origin.
