A case of superficially invasive well-differentiated cutaneous squamous cell carcinoma containing numerous mucin-producing cells both within the epidermal and dermal components is reported. Histological, histochemical and immunohistochemical overlap exists between these cells and those of extramammary Paget's disease. The presence of mucinous metaplasia within this tumor supports an intraepidermal origin for extramammary Paget's disease.