Vulval acne: a case series describing clinical features and management.

Intermittent inflammation of the vulval pilosebaceous units is common and usually self-limiting, but some patients experience recurrent and more troublesome symptoms. There is a scarcity of information on this problem. We describe the clinical and histological features in these patients and the response to treatment. A retrospective, observational study of 16 patients with this phenomenon of recurrent, protracted folliculocentric inflammation of the vulval pilosebaceous unit was performed. Details on the clinical features, histology and response to treatment were collected. Mean age at presentation was 32 years (range 21-45). All patients reported recurrent painful papules and pustules on the labia majora and labia minora. Nine patients reported a cyclical pattern to the development of lesions, with premenstrual exacerbation being most common. Histological examination of these lesions showed a folliculocentric microabscess formation surrounded by an acute and chronic inflammatory cell infiltrate, with a focal foreign-body granulomatous reaction. All our patients responded well to tetracycline, antiandrogenic or retinoid therapy. We propose the term 'vulval acne' for this condition and propose a stepwise approach to its management. We hope to highlight this as a common but underreported entity.

Melanoma in congenital melanocytic naevi.

Congenital melanocytic naevi (CMN) are a known risk factor for melanoma, with the greatest risk currently thought to be in childhood. There has been controversy over the years about the incidence of melanoma, and therefore over the clinical management of CMN, due partly to the difficulties of histological diagnosis and partly to publishing bias towards cases of malignancy. Large cohort studies have demonstrated that melanoma risk in childhood is related to the severity of the congenital phenotype. New understanding of the genetics of CMN offers the possibility of improvement in diagnosis of melanoma, identification of those at highest risk, and new treatment options. We review the world literature and our centre's experience over the last 25 years, including the molecular characteristics of melanoma in these patients and new melanoma incidence and outcome data from our prospective cohort. Management strategies are proposed for presentation of suspected melanoma of the skin and the central nervous system in patients with CMN, including use of oral mitogen-activated protein kinase kinase inhibitors in NRAS-mutated tumours.

The spectrum of histopathologic patterns secondary to the topical application of EMLA® on vulvar epithelium: clinicopathological correlation in three cases.

EMLA(®) (eutectic mixture of local anesthetics, 2.5% each of lidocaine and prilocaine in an oil and water emulsion) is used as a topical anesthetic. We report three cases of EMLA(®) -induced histopathologic changes on the vulvar epithelium. While there are some similar histopathologic features to those reported in extragenital skin, we describe additional findings on vulvar epithelium, which, to our knowledge, have not been reported previously. The patients presented with clinical signs suggestive of lichen sclerosus or erosive lichen planus (LP), but were all confirmed histopathologically as LP. The biopsy was taken after 15 min of EMLA(®) application and intradermal injection of 1% lidocaine. Blistering prior to intradermal lidocaine and the biopsy procedure was observed in two patients. The histopathologic changes observed in the epithelium included pallor of the upper epidermis, mild spongiosis, intraepidermal subcorneal and suprabasal acantholysis, congestion of the papillary dermal capillaries and extravasated erythrocytes. Basophilic granules were present, but rare, while the necrosis with multifocal clefting was more marked than in extragenital skin. It is important to be aware of these changes occurring on genital mucosa; these may occur in the absence of clinical signs and may obscure the primary underlying pathology, thus representing a diagnostic pitfall.

The histopathologic spectrum of regression in atypical fibroxanthoma.

BACKGROUND: Atypical fibroxanthoma (AFX) with prominent fibrosis, sclerosis and hyalinization, and near-total tumor regression is rare. METHODS: Eight cases of AFX presenting with fibrosis were reviewed as to their tumor architecture, the degree and pattern of fibrosis and the associated inflammatory cell infiltrate. RESULTS: Seven of eight cases had an exophytic architecture, with ulceration in one case. The degree of fibrosis ranged from 10% to 90%. Early fibrosis (2/8 cases) occurred as thickened sclerotic collagen bundles, either dispersed between the neoplastic cells or as septa imparting a multilobular appearance. Advanced fibrosis (6/8 cases) was associated with lamellar sclerosis, keloidal features, hyalinization and with near-total tumor replacement. Prominent fibrosis rimming the periphery was present in all tumors. An associated lymphoid cell infiltrate with plasma cells and occasionally eosinophils was observed. CONCLUSIONS: Fibrosis with prominent sclerosis and hyalinization replacing the tumor is rare in AFX. Advanced fibrosis, in the absence of a history of prior trauma or surgery, may indicate spontaneous regression. These cases emphasize the importance of recognizing this subset of AFX in order to avoid misinterpretation, particularly in cases with few residual atypical cells.

Squamomelanocytic tumor: an unusual and distinctive entity of uncertain biological potential.

We report a case of a squamomelanocytic tumor of the skin. Clinically, the lesion was felt to be a melanocytic or vascular tumor but histologically was characterized by epithelioid cells with focal squamous differentiation. Immunohistochemical staining showed that half of cells stained with MNF116 and a smaller proportion stained with S100 and Melan A. A third population did not stain with either set of antigens. The lesion has some similarities to a melanocytic matricoma but no evidence of matrical differentiation. The biological potential of this distinctive tumor is not known because so few have been reported.