男性生殖器乳房外柏哲德氏症之跨團隊診療：個案報告

蔡祐婷、蔡佳宏

高雄長庚紀念醫院泌尿科

Multidisciplinary Management of Penile and Scrotal Extramammary Paget Disease: A Case Report

You-Ting Tsai, Chia-Hung Tsai

Department of Urology, Kaohsiung Chang Gung Memorial Hospital

Introduction

Extramammary Paget disease (EMPD) is an uncommon malignancy typically arising in skin rich in apocrine glands. Diagnosis may be delayed and challenging, because its clinical presentation—characterized by erythematous plaques—mimics eczema or dermatitis.

Case presentation

An 80-year-old man presented with a 6-month history of an asymptomatic rash on his external genitalia. Physical examination revealed a well-demarcated erythematous plaque extending across the penis, scrotum and lower abdomen. No inguinal lymphadenopathy was detected. A punch biopsy confirmed the diagnosis of extramammary Paget disease. A systemic evaluation for a potential underlying malignancy was performed. Cystoscopy and colonoscopy revealed negative findings. Chest and abdominal CT demonstrated a solid nodule in the right upper lobe; however, the patient declined bronchoscopy for tissue diagnosis. After detailed counseling, the patient provided informed consent for surgery. A multidisciplinary surgical approach was undertaken, including outpatient mapping biopsies by dermatology, tumor excision with partial penectomy by urology, and defect reconstruction with a rotation flap and split-thickness skin graft by plastic surgery. The patient recovered well, and a 6-month follow-up showed no clinical evidence of disease recurrence.

Discussion

Extramammary Paget disease (EMPD) is an uncommon, slow-growing intraepithelial adenocarcinoma that typically arises in apocrine gland–rich skin. In men, EMPD most commonly affects the perianal region; involvement of the penis and scrotum is exceedingly rare. Clinical symptoms vary from asymptomatic plaques to pruritus, pain, or discharge. Lesions typically present as well-demarcated erythematous plaques, which may be accompanied by erosion, ulceration, hypopigmentation, nodules, or eczematous changes. A critical component of management is screening for secondary malignancies, as 10-30% of EMPD cases are associated with underlying visceral cancers. While surgical excision remains the primary treatment, alternative options such as radiotherapy, photodynamic therapy, or topical imiquimod (5%) may be considered for non-surgical candidates. Outpatient mapping biopsies may aid in determining the approximate tumor-free margin prior to major resection. Intraoperative frozen sections are recommended to guide the extent of resection. Histologically, the disease is defined by Paget cells: large, pale cells with abundant eosinophilic cytoplasm located within the epidermis. While most cases of EMPD are confined to the epidermis, the tumor can invade the dermis, extend into soft tissues, and metastasize to regional lymph nodes and distant organs. In immunohistochemical profile, EMPD typically shows CK7 and CEA positivity with p63 and SOX10 negativity, whereas secondary EMPD may exhibit CK20 and CDX2 positivity with GCDFP15 and GATA3 negativity.

Conclusion

This case illustrates that extensive male genital EMPD can be successfully managed through a multidisciplinary surgical approach, including outpatient mapping biopsies by dermatology, tumor excision with partial penectomy by urology, and defect reconstruction by plastic surgery. The use of mapping biopsies and specialized reconstructive techniques is vital to ensuring clear oncological margins while preserving functional outcomes for the patient.