Polat, MuallaTuman, Bengü AltunayŞahin, AslıDoğan, ÜmitBoran, Çetin2021-06-232021-06-2320161396-02961529-8019https://doi.org/10.1111/dth.12385https://hdl.handle.net/20.500.12491/8632Dear Editor Nevus comedonicus (NC) is a rare epidermalhamartoma of unknown etiology, most com-monly located on the head and neck (1). It ischaracterized by groups of dilated follicular ori-fices resembling comedones, filled with firmhyperkeratotic plugs (1). Although most casesare located unilaterally on the head, neck, andtrunk, the lesions may have a linear or blasch-koid distribution and rarely occur bilaterally(2–8). Histopathologically, the lesions are char-acterized by closely arranged, dilated-invaginated follicular openings containinglamellar keratin and cystic formations. Half ofthe cases are congenital and half develop duringchildhood, usually before the age of 10 years(4–6). Most NC cases are isolated. When NC isassociated with anomalies in the central nervesystem, eye, or skeletal system, and adnexaltumors, it is called NC syndrome (6). We reportlate-onset NC of both eyelids due to its rarity,atypical bilateral localization, and association with bladder cancer.eninfo:eu-repo/semantics/closedAccessBladder CancerTopical TretinoinBilateral nevus comedonicus of the eyelids associated with bladder cancer and successful treatment with topical tretinoinLetter10.1111/dth.12385296479481275020872-s2.0-84982937913Q1WOS:000390561300024Q4