title: Proliferating trichilemmal cyst with focal calcification.
abstract: A 64-year-old man presented with a superficial, well-demarcated, skin-colored tumor on the left posterior scalp that measured 4 x 5 x 6 cm. The tumor was nearly hairless, rubbery, non-tender, and mobile over the underlying subcutaneous tissues. The lesion had grown slowly since arising approximately 30 years ago. Treatment options were declined in the past. However, with relatively more rapid growth over the past five years, the nodule began to cause intermittent pain and interfere with the patient's ability to lie on his back. The patient denied a history of similar lesions in himself or his family. A biopsy specimen showed a ruptured proliferating trichilemmal cyst with focal calcification. Complete excision is recommended for all benign proliferating variants owing to their potential for locally aggressive behavior and malignant transformation.
authors.affiliation: Department of Dermatology, New York University, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Anolik
authors.forename: Bahar
authors.initials: B
authors.lastname: Firoz
authors.forename: Ruth F
authors.initials: RF
authors.lastname: Walters
authors.forename: Shane A
authors.initials: SA
authors.lastname: Meehan
authors.forename: Hui C
authors.initials: HC
authors.lastname: Tsou
authors.forename: Michael
authors.initials: M
authors.lastname: Whitlow
authors.forename: Brent
authors.initials: B
authors.lastname: Wainwright
mesh_terms: D002114:Calcinosis / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D018450:Disease Progression; D004814:Epidermal Cyst / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D012536:Scalp Dermatoses / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery