Pigmented Plaque in the Axilla

Abstract

A woman in her 70s presented with an enlarged and variegated plaque on her left axilla, which she had had for 4 years. The lesion started as a small eczematous, pink-to-brown plaque. As the lesion was asymptomatic and slow growing, she did not initially seek treatment. Recently, the color of the lesion had changed to an alarming dark brown color (Figure , A). No breast mass or lymphadenopathy was observed. Her medical and family history was unremarkable. A skin biopsy specimen was obtained and submitted for further histopathologic analysis. Clinical image A Hematoxylin-eosin B EMA stain C HMB-45 stain D Figure. A, Clinical presentation of pigmented plaque in the axilla with well-demarcated margins. B, Histologic findings revealed an intraepidermal neoplasm consisting of pagetoid cells, characterized by round, pale, vacuolated cytoplasm, and large pleomorphic nuclei (hematoxylin-eosin; original magnification ×200). C, Immunohistochemical findings showed positive staining for EMA (original magnification ×200). D, The lesion was surrounded by numerous reactive dendritic HMB-45-positive melanocytes scattered among the tumor cells (original magnification ×200). WHAT IS YOUR DIAGNOSIS? A. Pagetoid Bowen disease B. Inverse lichen planus C. Pigmented extramammary Paget disease D. Superficial spreading melanoma Clinical Review & Education

Extramammary Paget's disease involving the axilla: case series and literature review

“…Brownish to pigmented patches are seen in some cases as a subtype, termed pigmented EMPD. 5 Hypopigmentation was also observed in some patients. It may occur unilaterally, bilaterally, or simultaneously with the genital area.…”

“…Similar to typical EMPD, axillary EMPD usually presents with well‐defined erythematous patches or plaques. Brownish to pigmented patches are seen in some cases as a subtype, termed pigmented EMPD 5 . Hypopigmentation was also observed in some patients.…”