trichoadenoma is a rare benign tumor , with multiple cystic structures closely resembling the infundibular structures of the hair follicle .
it presents as a non - specific nodule over the face or buttocks , however , unusual sites such as the neck , upper arm , thigh shoulder , and shaft of the penis may also be affected .
ours is a case of a 60-year - old female with a trichoadenoma over the left labia majora , which presented as a slow growing nodular plaque .
a 60-year - old married female patient presented to us with asymptomatic gradually increasing skin lesion on vulva since 2 years .
examination revealed a firm , nontender , nodular plaque of 3.5 cm  2.5 cm along with a few shiny papules along the right labia majora [ figure 1a ] .
the left labia majora , labia mijora , clitoris , and perianal areas were not involved .
differential diagnoses considered were fibrosis lymphangioma circumscriptum , giant trichoepithelioma , sarcoidosis , lupus vulgaris , and deep fungal infection .
( c ) post - treatment - 2 months , healing with post - inflammatory hyperpigmentation histopathology from the lesion showed numerous horn cysts present throughout the dermis surrounded by eosinophilic cells [ figure 2a ] .
few of the cyst walls were lined by eosinophilic epidermal cells and contained keratin [ figure 2b ] ; thereby leading to a diagnosis of a less known adnexal tumor trichoadenoma .
( a ) 10 view : showing numerous horn cysts present throughout the dermis . ( b ) 40 view : showing cyst walls lined by eosinophilic epidermal cells , containing keratin
trichoadenoma of nikolowski is a rare , follicular tumor considered as a neoplastic process by some authors and benign malformation by some others .
clinically it presents as a solitary slow growing grayish nodule measuring up to 1.5 cm in diameter , seen over the face ( 57.5% ) and buttocks ( 24.2% ) .
other uncommon sites of involvement are the neck , upper arm , thigh , shoulder and shaft of penis
. it may also present as a chronic discharging nodule or as an ulcerated growth .
rare case reports of trichoadenoma in association with intradermal melanocytic nevus , sebaceous carcinoma , basal cell carcinoma , syringocystadenoma papilliferum have also been recorded .
verrucous variants of trichoadenoma have also been reported . though it is a tumor of adulthood , infants as old as 20 months
numerous horn cysts are present surrounded by eosinophilic cells . in some instances , a single layer of flattened granular cells is interpolated between the horn cysts and surrounding eosinophilic cells .
moreover , the histological similarity of trichoadenoma with trichoepithelioma suggests the development of immature hair structures .
however , because the cyst wall consists of epidermoid cells and keratinization may take place with the formation of keratohyalin , it has been suggested that the tumor differentiates largely toward the infundibular portion of the pilosebaceous unit .
the keratin profile expression of this tumor supports the theory that it differentiates towards the follicular infundibulum and the follicular bulge region .
, we used co2 laser at 9.0 watts with 100 mm hand piece ( 1.0 mm spot size ) in superpulse mode to ablate the growth under local anesthesia [ figure 1b ] .
there has been no recurrence so far and the normal vulvar anatomy has been maintained .
the trichoadenoma is a mystifying follicular tumor . though it is known to occur on the face and buttocks , newer cases with unusual manifestations
are being reported . to the best of our knowledge , a histopathologically proven large trichoadenoma over the vulva has not been reported .
 trichoadenoma of nikolowski is a rare , benign , well differentiated , slowly growing tumor of the hair follicle which was first described in 1958 by nikolowski . 
 it usually occurs as a solitary nodular lesion between 3 and 15 mm in diameter . 
 it commonly occurs on the face or the buttocks . 
 herein we report a case of a slowly growing nodular plaque over the vulva of a 60-year - old female , histopathologically proven to be a trichoadenoma . 
 the lesion was completely removed by ablative carbon dioxide laser ( co2 ) . 
INTRODUCTION
CASE REPORT
DISCUSSION
CONCLUSION