Extramammary Paget's disease (EMPD) is most often observed in areas that are rich in apocrine glands. Patients usually present with eczematous crusted or excoriated gray white plaques. [1] EMPD can present as carcinoma in situ or as invasive disease that can subsequently metastasize to lymph nodes and distant sites. [2] There is also a familial EMPD, although, the genetic bases are still unknown. [3] Effective chemotherapy for advanced EMPD has not yet been established. [4] Trastuzumab is a humanized monoclonal antibody which selectively targets human HER2. The HER2 protein is sometimes overexpressed in EMPD and the HER2 signal pathway leads to vigorous tumor cell proliferation. In such cases, therapy employing Trastuzumab combined with paclitaxel or using Trastuzumab alone has already been proved to be effective in some cases. [5],[6],[7] Here we report two case of scrotal EMPD in two brothers.

Case 1A

67-year-old Chinese man presented with a 2-year history of left scrotal itchy eczematous skin lesion which had gradually increased in size and a 1-year history of left inguinal lymphadenopathy. He was referred to Urology Department of our hospital in January 2013. On physical examination, an erosive erythematous plaque measuring 50 × 60 mm was noted on the left side of the scrotum. Enlarged lymph nodes were palpated in his left (2 cm and 1cm in size) and right (1 cm in size) inguinal area. His past history included subtotal gastrectomy and colorectal polyposis excision, which was performed 10 years ago. Histological examination of both specimens showed no malignancy. Therefore, the patient has had an extensive cancer work-up. The tumor markers were within normal range: Carcinoembryonic antigen 3.03 ng/mL (normal range, 0-5 ng/mL), alpha-fetoprotein 2.84 ng/mL (normal range, 0-13.4 ng/mL), prostate-specific antigen 0.471 ng/mL (normal range, 0-4 ng/mL), Carbohydrate antigen 12-5 8.30 U/mL (normal range, 0-35 U/mL), Carbohydrate antigen 19-9 19.00 U/mL (normal range, 0-37.00 U/mL), and Carbohydrate antigen 15-3 19.10 U/mL (normal range, 0-31.30 U/mL). While admitted to the hospital, the patient underwent excision of primary site with a sentinel node biopsy (SLNB) of the left inguinal lymphadenopathy. A biopsy of the skin lesion showed that Paget's cells were single dispersed or arranged in rows or small nests concentrated above the basal layer of the epidermis, however, a little of them invaded to dermis [Figure 1]a. Metastatic tumor cells were found in the SLNB. Immunohistochemistry of the skin showed cytokeratin 7(CK7)+, CK20 -, gross cystic disease fluid protein 15(GCDFP15)-, S100 protein -, melanoma associated antigen (HMB45)−, epithelial membrane antigen (EMA)+, carcinoembryonic antigen (CEA)+, Ki67+ (30%), and anti-cytokeratin (CAM 5.2) +. The diagnosis of invasive EMPD was confirmed histochemically and immunohistochemically.