[Clinical and dermoscopic features of pigmented Bowen disease].

could be discerned. Biopsy showed a tumor confined to the epidermis with acanthosis, a certain degree of papillomatosis, markedly atypical cells, and mitotic figures, with a completely intact basement membrane. Immunohistochemical studies using markers such as Melan-A and pancytokeratin cocktail confirmed the nature of the tumor, which was diagnosed as a case of pigmented Bowen disease. We excised the lesion and, 18 months after the procedure, the patient remains asymptomatic. Bowen disease is a relatively common tumor that is considered to be an intraepidermal squamous cell carcinoma.1-3,6 The pigmented forms of this tumor— although uncommon (less than 2% of cases1,5)—require differential diagnosis with other pigmented tumors and with melanoma in particular. Although pigmented Bowen disease can appear at any site, it is rarely found in the genital region, and only 3 cases have been described in the literature to date.1,4,7 Various etiologic factors have been implicated in the development of the disease, including chronic exposure to UV radiation and arsenic,1,2 trauma, ionizing radiation, and human papillomavirus (HPV) infection. Indeed, HPV infection is particularly important in the development of tumors at sites not exposed to sunlight or in areas often infected by the virus, such as the perigenital region. Dermoscopy is a noninvasive technique that improves diagnostic accuracy in the case of pigmented lesions. Several dermoscopic features of Bowen disease have been described.2,3,8-10 The most characteristic and common findings for this tumor are shown in the Table. The most frequently observed such feature in Bowen disease is the multicomponent pattern.8 Of the criteria presented in the Table, the most specific to Bowen disease are presence of atypical vascular To the Editor: Bowen disease is described as an in situ squamous cell carcinoma that, like other skin tumors, can present as a pigmented tumor, thereby necessitating differential diagnosis with other pigmented tumors.1-6 We present the case of a 48-year-old woman with no relevant personal or family history who was referred to the melanoma unit of our department with suspected diagnosis of “perianal melanoma.” She reported that the lesion had appeared approximately 3 years earlier and that it had been growing slowly ever since. Physical examination of the perianal region revealed an asymmetric poorly demarcated multicolor pigmented tumor that measured 3.5 × 2 cm and that was covered with whitish scales (Figure 1). In the dermoscopic examination (FotoFinder system), the only feature characteristic of melanoma was an aggregate of globules of irregular shapes and sizes in one part of the tumor; reticular pigmentation pattern, starburst pattern, and other features indicative of melanoma were not found. In the rest of the tumor, an atypical vascular pattern was observed comprising large, tortuous, irregular structures, some of which were rounded. In the lower part of the lesion, a verrucous whitish surface LETTERS TO THE EDITOR Actas Dermosifiliogr. 2008;99:419-27