Rare perianal extramammary Paget disease successfully treated using topical Imiquimod therapy

Background: Perianal Paget’s disease (PPD) is a rare intraepithelial adenocarcinoma of the anal margin. Primary PPD likely represents intra-epithelial neoplasm from an apocrine source, whereas secondary disease may represent“pagetoid” spread from an anorectal malignancy.

Case presentation: Histologic CDX-2 and CK20 are hallmark markers for colorectal-derived Paget’s cells. Interestingly, our primary PPD patient presented both positive and no internal malignancy was identified. In addition, a negative CK7 marker was observed in our case in contrast with previously reported. Surgical excision is the standard treatment; however, previous studies have demonstrated good response with Imiquimod 5% cream in patients with vulval extramammary Paget disease (EMPD). The efficiency of Imiquimod treatment for PPD has not been well described. Our PPD patient was successfully treated using Imiquimod 5% cream.

Conclusions: This study describes a primary cutaneous PPD patient CDX-2+/CK20+/CK7- without invasion of the dermis and no associated colorectal carcinoma effectively treated using topical Imiquimod therapy, suggesting that Imiquimod might potentially be considered as a first-line treatment for PPD.

Perianal extramammary paget's disease associated with primary linitis plastica of the rectum: Report of a case

We report herein a case of perianal extramammary Paget's disease associated with primary linitis plastica of the rectum. An 82-year-old woman was admitted to our hospital for investigation and treatment of a perianal eczematous lesion. A skin biopsy of the lesion revealed perianal extramammary Paget's disease and a barium enema demonstrated diffuse narrowing with an irregular contour at the ampulla recti. Under a suspected diagnosis of linitis plastica of the rectum, an abdominoperineal resection was performed to resect both the rectal and perianal lesions with regional lymphadenectomy. Grossly, marked narrowing and wall thickness were observed at the lower rectum, and a histological diagnosis of signet ring cell carcinoma was confirmed. The perianal eczematous lesion revealed many atypical cells with clear cytoplasm, being Paget cells, throughout the entire epidermis. Sparse distributions of signet ring cells were also observed in the subcutaneous tissue beneath the perianal eczematous lesion. The pathogenesis of perianal extramammary Paget's disease in this patient was therefore considered to be an intraepidermal extension of primary linitis plastica of the rectum.