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histopathology demonstrates large single cells or cell nests throughout the epidermis in paget 's disease .
tumor cells are positive for periodic - acid - schiff stain ( pas ) , cytokeratin 7 ( ck7 ) , and carcino - embryonal antigen ( cea ) but remain negative for s100 or hmb-45 .
immunohistology helps to distinguish iempd for pagetoid melanoma ( s100 and hmb-45 positive , but ck7 , cea , and pas negative ) .
upper nests or a mixture of at least three patterns has been considered as suggestive for iempd .
iempd shows a complete loss of wnt ( wingless - type mmtv integration site)-5. in addition , several protein kinases involved in the c - jun amino - terminal kinase pathway are overexpressed in iempd : hematopoietic progenitor kinase-1 , mitogen - activated protein / extracellular signal - related protein kinase kinase kinase-1 , and phosphomitogen - activated protein kinase kinase-4 .
the over expression of her-2/neu ( c - erbb-2 ) is correlated to invasiveness of lymph node metastasis .
five - year relative survival for invasive empd is 91.2% . among european patients 8.6% developed other malignancies .
the highest increased risk of developing a second primary tumour was found in the first year of follow - up or being female .
a 70-year - old causasian male patient of good general health presented with a persistent scaling erythematous lesion on his groins with ill - defined margins .
the lesions were slow growing for more than 5 years . topical treatment with corticosteroids or anti
on examination we observed an extensive erythematous lesion of groins , perineum and proximal parts of scrotal skin with peripheral scaling and central oozing [ figure 1 ] .
inguinal lymph nodes were not palpable . clinical aspect of extensive extramammary invasive pagets disease with involvement of groins scrotum and perineum laboratory investigations were unremarkable except a slightly increase level of carcinoembryonal antigen ( cea ) of 2.2 g / l .
we took a diagnostic biopsy from the left groin in the centre of the lesions .
screening for second tumour including skin ( total body investigation including dermoscopy ) , lung ( computerized tomography ) , prostate ( digital examination , ultrasound and prostate - specific antigen ) , and git ( coloscopy ) remained negative .
treatment and course : we performed complete surgical excision with delayed mohs techniques [ figure 2 ] .
the histopathological work - up revealed a paget carcinoma ( apocrine adenocarcinoma ) surrounded by intraepidermal paget 's disease [ figure 3 ] .
therefore , re - excision of the margins was done twice with delayed mohs technique , i.e. , complete examination of all margins .
wound bed was prepared by repeated topical co2 application under plastic foil for 20 min .
the resulting defect was closed by split - skin mesh - graft and the scrotum was partially reconstructed by extension of scrotal skin [ figure 4 ] .
the healing was uneventful and the outcome was functionally and esthetical very good [ figure 5 ] .
surgical situs after mohs surgery histopathology of the tumor with pagetoid cell proliferations and invasive growth ( h and e , 4 ) mesh - graft split skin transplantation after induction of granulation by topical co2 good functional and esthetic outcome during follow - up of three months the patient was relapse - free .
a regular follow - up every 3 months during the first year and twice a year for a total of five years is planned .
the differential diagnosis includes inverse psoriasis , eczema , intertrigio , tinea and mycosis fungoides .
the anogenital region is the most common involved area , but scrotal disease is less common . standard therapy is complete surgical excision with 2 cm to 5 cm safety margin or mohs surgery.[1013 ] mohs surgery may be supported by immunostaining for cytokeratin 17 expressed by empd .
recurrence rates after standard surgical excision range from 33% to 62.5% versus 16% to 28% after mohs surgery.[1113 ] non - surgical treatments have been used either in non - invasive empd or recurrent empd .
topical imiquimod may produce long - term remissions in smaller tumors but not in all.[1417 ] photodynamic therapy fails to achieve complete remissions especially in larger tumours .
other options include topical 5-fluorouracil , topical bleomycin , co2-laser , docetaxel , and radiotherapy .
whereas surgery remains the golden standard , in extensive disease defect closure may become difficult .
various techniques have been used including split skin mesh graft transplants with or without vacuum - assisted closure , and a number of flaps , especially when deep arteries are exposed . although flaps allow a rapid closure of defects , the long term outcome of pendiculated flaps often bears the risk of local lymphedema .
this can be circumvented by preparation of wound ground and delayed split skin grafting as in our case .
extramammary paget 's disease is uncommon . 
 diagnosis has to be confirmed by histopathology . 
 treatment is a challenge in cases with extended tumors . 
 we present a 70-year - old male patient with extensive genitoanal paget 's disease . 
 mohs surgery is the gold standard in such cases . 
 details of the surgical planning are discussed including wound bed preparation . 
 radiotherapy may be an alternative .