A dilated pore of Winer will present as a single, enlarged pore. The pore may be occluded by a keratin plug with softer, white, keratin material beneath.  They are asymptomatic, and the surrounding skin appears normal however a background of actinic damage may be noted.  Inflammation or infection along with pain and swelling can occur with manipulation.  Although they have a predilection for the head and neck, particularly the face, they can also present on the trunk, most commonly the back.  Patients are usually middle-aged or older and may report a previous history of severe acne.

A dilated pore of Winer is usually a clinical diagnosis.  Histopathologic examination is not required but can be performed if the diagnosis is uncertain or in cases where the lesion is excised for cosmetic purposes.  No other testing or work-up is needed.

No treatment is required for a dilated pore of Winer.  Removal can be performed for cosmetic concern. Excision in an elliptical fashion or by punch biopsy is usually curative.[6] Merely removing the keratin material can be done using a comedone extractor. However, keratin will gradually re-accumulate within the lesion. Destructive techniques such as electrodesiccation, electrocautery, laser surgery, dermabrasion, and cryotherapy are less effective due to the deeply situated base of the invagination.[5]  There are no effective medical treatments for these lesions.

A dilated pore of Winer and a typical nevus comedonicus can be easily differentiated clinically as the latter is a group of multiple keratin-filled openings.  A solitary lesion of a nevus comedonicus and a DP may only be differentiated histologically. The age of onset differs between the two lesions in that a dilated pore of Winer presents in the middle-aged to elderly while an NC presents at birth or during childhood.[2]  A Pilar sheath acanthoma closely resembles a dilated pore of Winer clinically as both have a central dilated opening filled with keratin and both commonly occur on the face of older adults.  Pilar sheath acanthomas occur most commonly on the upper cutaneous lip and have a more papular component compared to the dilated pore of Winer.  Histologically the pilar sheath acanthoma has a more proliferative wall with thicker acanthotic projections radiating from the central cavity, which may contain keratin cysts, squamous eddies, or sebaceous ducts.[1]  An epidermal inclusion cyst with a punctum may also clinically resemble a dilated pore of Winer and can also commonly occur on the face and trunk. Epidermal inclusion cysts have a more nodular component which is usually freely mobile and does not contain a keratin plug. They contain thick, cheesy, keratin material which has a foul odor when expressed.  Histologically epidermal inclusion cysts differ in that they present as a true cyst in the dermis with a lining of stratified squamous epithelium with a granular layer and filled with loose lamellar keratin.  Although rare, some basal cell carcinomas (BCC) can have an associated dilated pore. These large-pore BCCs tend to occur on the face of men and may be confused for a DP.  A large-pore BCC will have a history of slowly enlarging over years and may or may not have keratin debris.  Patients will tend to have thick sebaceous skin and have a history of tobacco use.[7]

Complete excision of the lesion is curative. Incomplete excision can result in recurrence from the remaining infundibular lining.  To date, there have been no reports of death associated with a dilated pore of Winer.  Also, there have been no reports of syndromes associated with this entity. There have been rare case reports of other malignant cutaneous neoplasms such as basal cell carcinoma and squamous cell carcinomas arising in dilated pores of Winer. However, these are most likely coincidental.[8],[9]  There has been one case report of a trichoblastoma arising in a dilated pore of Winer.[10]  Inflammation or infection of the surrounding skin can result from manipulation of the lesion by the patient in an attempt to remove the keratin plug.

Complications of surgical removal include scarring, infection, and bleeding.  Infection risk after surgery can be minimized by using proper aseptic or clean technique.  Infection prior to or following surgery can be treated using topical or oral antibiotics depending on severity.

A dilated pore of Winer is best managed by an interprofessional team that includes a dermatologist, primary care provider, and nurse practitioner. Although these lesions are benign, a biopsy may be required to rule out malignancy in individuals who have an atypical presentation. The majority of patients seek medical help for cosmesis. The prognosis for most patients is excellent.