Extramammary Paget Disease



Extramammary Paget Disease


Maria Angelica Selim, MD

Russell Ball, MD





Key Facts


Terminology



  • Intraepidermal adenocarcinoma (primary or secondary) with frequent extension into adnexal structures; rarely invasive


Clinical Issues



  • Often, clinically misdiagnosed as inflammatory process (dermatitis)


  • Moist, red, eczematous-appearing plaque


  • Prognosis worse if nodules visible, elevated CEA levels, > 1 mm dermal invasion, lymph node metastasis, underlying malignancy


Microscopic Pathology



  • Nests &/or single cells and, less commonly, glands confined to basal and parabasal or higher layers


  • Associated proliferative epidermal lesions in 1/3


  • Invasive component in up to 48% of primary EMPD


Ancillary Tests



  • Primary and secondary EMPD: CAM5.2, CEA, EMA positive and ER, PR, MART-1/Melan-A, tyrosinase, MITF, and HMB-45 negative; rarely S100(+)


  • Primary: CK7, GCDFP-15, MUC1, MUC5 positive


  • Secondary anorectal: CK20, CDX-2, MUC2 positive


  • Secondary urothelial: CK7, CK20, and uroplakin-3 positive


  • Secondary cervical: p16 positive


Top Differential Diagnoses



  • Squamous cell carcinoma


  • Melanoma


  • Clear cell papulosis


  • Sebaceous carcinoma







Extramammary Paget disease often presents as a scaly, erythematous plaque, mimicking an inflammatory process. (Courtesy L. Edwards, MD.)






Paget cells are typically found singly image or in variably sized nests image at the lower levels of the epidermis, with preservation but compression of basal keratinocytes.


TERMINOLOGY



Abbreviations



  • Extramammary Paget disease (EMPD)


Synonyms



  • Mammary Paget disease (MPD)



Definitions



  • Primary (85%)



    • Intraepidermal adenocarcinoma with frequent extension into adnexal structures; rarely invasive


    • No underlying malignancy


  • Secondary (15%)



    • Intraepidermal adenocarcinoma associated with underlying (extracutaneous) malignancy (cervical, anorectal, urinary)


ETIOLOGY/PATHOGENESIS


Theories Regarding Cell of Origin



  • Pluripotential epidermal or adnexal stem cells


  • Clear cells of Toker



    • Traditionally accepted as origin of mammary Paget disease (CK7 positive and CK20 negative cells present at opening of lactiferous ducts)


    • Recently identified as normal constituent of vulvar, perineal, and perianal skin at ostia/opening of anogenital mammary-like glands


    • Greater frequency of Toker cells in areas of extramammary Paget disease


  • Bartholin gland


  • Apocrine glands


  • Anogenital mammary-like glands




CLINICAL ISSUES


Epidemiology



  • Incidence



    • Rare (˜ 2% of vulvar neoplasms)


    • Most common vulvar adnexal malignancy (primary EMPD)


  • Age



    • Typically after 4th decade, peak at ˜ 65 years


  • Ethnicity



    • Caucasians


Site



  • Anogenital skin


  • Labia majora > labia minora > clitoris


Presentation



  • Moist, red, eczematous-appearing plaque


  • Often pruritic


  • Rarely hyperpigmented


  • May be ulcerated


  • Multifocal extent may be clinically apparent


  • Clinically, may mimic inflammatory process (dermatitis), seborrheic keratosis, pigmented condyloma, or pigmented vulvar intraepithelial neoplasia



Treatment

Tags:
Jul 7, 2016 | Posted by in PATHOLOGY & LABORATORY MEDICINE | Comments Off on Extramammary Paget Disease

Full access? Get Clinical Tree
Get Clinical Tree app for offline access