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fibroepithelioma of pinkus ( fep ) is generally considered a rare basal cell carcinoma subtype   although some consider it a variant of trichoblastoma .
the clinical appearance of fep is typically that of a solitary , flesh - colored , dome - shaped sessile papule or plaque , but large pedunculated , polypoid or ulcerated cases have also been reported .
clinically it can resemble several benign skin tumors , including dermal nevus , pedunculated fibroma , acrochordon and seborrheic keratosis .
fep is more common in females and is most frequently located on the lumbosacral region , although it may occur anywhere on the body surface .
it typically develops after the fourth decade of life , but two pediatric cases have also been described .
the dermatoscopy of fep , since first described in 2005   has been well summarized by reggiani et al .   as follows : 
 polymorphous vessels consisting mainly of fine , focused , short arborizing and dotted vessels , the latter mainly located at the periphery of the lesionshort white streaks  also called 
( visible only on polarized dermoscopy)in pigmented fep , gray - brown areas and gray - blue dots polymorphous vessels consisting mainly of fine , focused , short arborizing and dotted vessels , the latter mainly located at the periphery of the lesion short white streaks  also called 
( visible only on polarized dermoscopy ) in pigmented fep , gray - brown areas and gray - blue dots in addition to dermatoscopy , reflectance confocal microscopic findings also have been well described .
a variable amount of plump , bright cells corresponding to melanin - laden macrophages were also present .
an 83-year - old man presented to a primary care skin cancer clinic in melbourne , australia for a routine skin cancer examination .
he pointed out two adjacent soft , exophytic lesions arising from the superior aspect of his umbilicus .
these had first appeared some seven years earlier and had been slowly growing in size since .
he had a history of multiple non - melanoma skin cancer excisions since the age of 70 . in the last five years
, three separate basal cell carcinomas had been excised from his lumbar back and one from his left upper arm .
a well - differentiated squamous cell carcinoma had been excised from his left forearm six months previous .
the umbilical lesions had been overlooked on several previous examinations as most likely dermal nevi or acrochordons .
a whole body skin examination was undertaken with the aid of a heine delta 20 non- polarizing dermatoscope ( heine optotechnik , herrshing , germany ) .
digital clinical and dermatoscopic images were taken with a medicam 800 fotofinder non - polarizing camera ( fotofinder systems gmbh , aichner , birnbach , germany ) the dermatoscopy images being at 20 magnification .
there was severe actinic damage skin of face , upper trunk and distal limbs with multiple solar lentigines and scattered actinic keratoses .
the lesions of interest were immediately adjacent and appeared to arise from the superior aspect of the umbilicus .
each measured 10  12 mm diameter and were both of soft , polypoid nature .
the left - hand lesion had no exudate and notable brown / gray pigmentation distally ( figures 1 and 2 ) .
dermatoscopy of the right - hand , nonpigmented lesion revealed the presence of multiple small erosions along with fine polymorphic peripheral vessels on a pink / white background ( figure 3 ) .
dermatoscopy of the left - hand , pigmented lesion showed small ovoid gray structures , fine brown dots , arborizing vessels and a single erosion as might be found in a basal cell carcinoma ( figure 4 ) .
an excisional biopsy of both lesions was performed and the specimens were submitted for assessment by a specialist dermatopathologist .
these were not two clones of a single tumor . both lesions showed interconnecting and ramifying cords of basaloid epithelium set in a loose stroma , infiltrating through most of the dermis ( figures 5 and 6 ) . in the pigmented lesion ,
melanophages with distinct brown cytoplasmic granules were present within the stroma separating the basaloid trabeculae ( figure 7 ) .
the case we present is unique in that no previous case of two adjacent separate and independent adjacent fep has ever been described in the literature .
the case is also most unusual in in two further respects : 
 only one previous case of fep arising from the umbilicus has been reported .of further interest , one lesion is pigmented and the other nonpigmented .
it was suggested by the authors at that time that a pigmented fep was  a statistically very unlikely event  .
a year later , in 2005 , zalaudek presented the first published dermatoscopy image of an fep .
this lesion was also pigmented and showed the most unusual feature of white peripheral leaf - like structures . in 2006 the first case series detailing the dermatoscopic features of 10 histologically proven fep was published .
this was a pigmented plaque fep in a 13-year - old girl , which had slowly been growing on her abdomen since the age of 3 years . up to and including the reggiani et al .
review of the literature in 2013 , the dermoscopy and reflectance confocal microscopy of 24 fep had been reported . of these , 14 ( 58.3% ) were nonpigmented and 10 ( 41.7% ) were pigmented .
thus , to date pigmented fep approaches one - half of all reported cases  not as statistically unlikely as first proposed in the sentinel case report of 2004 .
it is possibly not prudent to draw conclusions on incidence based on a single case .
we present a unique case of separate and independent adjacent fibroepitheliomas of pinkus ( fep ) arising from the umbilicus in an 83-year - old man . of further interest , one 
 is pigmented and the other nonpigmented . 
 clinical , dermatoscopic and histopathological images are provided.a review of the published literature is undertaken to attempt to assess the incidence of pigmented versus nonpigmented fep . 
 of 24 published fep cases , 10 ( 41.7% ) have been pigmented . 
 thus to date pigmented fep comprise approaching one - half of all reported cases .