title: Agminate and plaque-type blue nevus combined with lentigo, associated with follicular cyst and eccrine changes: a variant of speckled lentiginous nevus.
abstract: Agminate and plaque-type blue nevi are rarely described. We report the occurrence of such a type of blue nevus associated with eccrine changes and a follicular cyst all arising on a macular brown background in a 38-year-old man. The patient presented numerous blue papules and a plaque, overlapping a light tan patch present since birth, on his left thigh. In addition, within the plaque, 3 papules, discharging at intervals a serous fluid, were present. Since the lesion hardened and enlarged, it was surgically excised. Histologic findings revealed a lentigo pattern of the epidermis, corresponding to the light tan macular background and a plaque-type blue nevus, and areas of eccrine ductal proliferations with a ruptured follicular cyst. The association of agminate and plaque-type blue nevus, arising on a light brown patch of lentigo, might represent a variant of speckled lentiginous nevus. Eccrine proliferations may be reactive in nature or represent a more complex hamartomatous lesion. The possibility of malignant transformation and the recent enlargement of the lesion caused by the ruptured follicular cyst convinced us to carry out a wide surgical excision.
authors.affiliation: Clinica Dermatologica IV, Ospedale S. Paolo, Milano, Italia.
authors.forename: R
authors.initials: R
authors.lastname: Betti
authors.forename: E
authors.initials: E
authors.lastname: Inselvini
authors.forename: M
authors.initials: M
authors.lastname: Palvarini
authors.forename: C
authors.initials: C
authors.lastname: Crosti
mesh_terms: D000328:Adult; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D004439:Eccrine Glands / Q000473:pathology*; D004817:Epidermis / Q000473:pathology; D005497:Follicular Cyst / Q000150:complications / Q000473:pathology* / Q000601:surgery; D006222:Hamartoma / Q000150:complications / Q000473:pathology; D006801:Humans; D007868:Leg Dermatoses / Q000150:complications / Q000473:pathology / Q000601:surgery; D007911:Lentigo / Q000150:complications / Q000473:pathology* / Q000601:surgery; D008297:Male; D018329:Nevus, Blue / Q000150:complications / Q000473:pathology* / Q000601:surgery; D012307:Risk Factors; D012422:Rupture, Spontaneous; D012878:Skin Neoplasms / Q000150:complications / Q000473:pathology* / Q000601:surgery; D013543:Sweat Gland Diseases / Q000150:complications / Q000473:pathology / Q000601:surgery; D013848:Thigh