A rare case of inverted follicular keratosis in an elderly male: Dermoscopic and histopathological overview with therapeutic response to imiquimod

Abstract

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Two Distinct Lesions of Inverted Follicular Keratosis of the Scalp: A Case Report

“…IFK is an uncommon benign tumor characterized by endophytic growth, predominantly on the follicular infundibulum [ 4 ]. The most common presentation is a single, non-pigmented verrucous papule on the face, typically appearing in middle-aged or elderly individuals and predominantly in men.…”

“…The diagnosis of IFK is uncommon and is generally established histopathologically as clinical differentiation from other lesions is difficult [ 7 ]. Extra caution should be noted as common clinical and pathological differentials includes warts, keratoacanthoma, squamous cell carcinoma, and basal cell carcinoma [ 4 ]. The specimens were sent for histopathologic examination, and for both lesions, the findings are consistent with the diagnosis of IFK.…”

“…The specimens were sent for histopathologic examination, and for both lesions, the findings are consistent with the diagnosis of IFK. In other literature [ 4 ], IFK of the upper eyelids has been associated with plugs of keratin, a dense inflammatory response characterized by inverted papillomatosis, a number of squamous eddies, and acanthosis. In this instance, there were no cellular atypia, nests of cells, or pathologic mitotic observed [ 4 ].…”

“…In other literature [ 4 ], IFK of the upper eyelids has been associated with plugs of keratin, a dense inflammatory response characterized by inverted papillomatosis, a number of squamous eddies, and acanthosis. In this instance, there were no cellular atypia, nests of cells, or pathologic mitotic observed [ 4 ]. It was also described that the histopathology examination for IFK may reveal stratified, squamous epithelium foci with hyperkeratosis and parakeratosis.…”

“…As the diagnosis of a lesion could harbor numerous clinical findings, histopathology, immunohistochemistry, and molecular pathology examinations should aid in the diagnosis of these lesions. According to some cases, the upper eyelid is a common predilection area for IFK [ 4 , 8 ]. A study reported a single, well-defined, asymptomatic, skin-colored plaque along the upper eyelid margin.…”