Thomas G. Salopek

Atypical mole syndrome: Risk factor for cutaneous malignant melanoma and implications for management

The incidence of malignant melanoma is increasing faster than that of any other cancer. It is important to identify subsets of the population at high risk of its development so that they can be observed more closely to identify early melanomas when they are curable. It has been reported worldwide that persons with the atypical mole (dysplastic nevus) syndrome are such a subset at increased risk. A risk gradient for the development of melanoma exists and varies from persons with one or two atypical moles and no family history of melanoma at one end of the spectrum to persons with the familial atypical multiple-mole melanoma syndrome at the other. Guidelines for the management of atypical mole syndrome are presented.

Trends in incidence of nonmelanoma skin cancers in Alberta, Canada, 1988-2007.

Background  Nonmelanoma skin cancer (NMSC) is the most common malignancy affecting caucasian populations and has been seeing global increases in incidence for decades.

Differentiation of atypical moles (dysplastic nevi) from early melanomas by dermoscopy.

Several conventional and new dermoscopic criteria are highly specific for diagnosing early melanomas. Until the reliability of the dermoscopic scoring systems has been validated, the presence of any combination of these specific features should elevate the index of suspicion for melanoma and prompt a biopsy to avoid missing this cancer.

Case Report of Darier Disease Localized to the Vulva in a 5‐Year‐Old Girl

Abstract: A 5‐year‐old girl with Darier disease had numerous verrucous papules coalescing into plaques on both labia major a of approximately one years duration. She was diagnosed as having genital warts, raising the suspicion of sexual abuse. Subsequently, a biopsy specimen from one of the vulvar lesions revealed histologic characteristics consistent with a diagnosis of Darier disease. The case is unusual for the age of onset and the site of initial involvement, and stresses the importance of including acantholytic disorders such as Darter disease in the differential diagnosis of a child with clinically verrucous lesions.

THE EPIDERMAL MELANIN UNIT IN THE PATHOPHYSIOLOGY OF MALIGNANT MELANOMA

The epidermal melanin unit (EMU) denotes the symbiotic relationship between a melanocyte and a pool of associated keratinocytes. We propose to show that alterations in the biology of the EMU are the main determinant of the different patterns of intraepidermal growth of melanocytes in lentigo maligna melanoma (LMM) and superficial spreading melanoma (SSM). They also appear to affect the biosynthesis of melanin and melanosomes during malignant transformation. Findings in histochemical studies with monoclonal antibodies generated against melanosomal proteins to produce different stains of melanocytes of normal skin, dysplastic melanocytic nevi (DMN), common melanocytic nevi (CMN), LMM, and SSM have led to the suggestion that the altered melanosome synthesis is a main phenotype in the pathophysiology in neoplastic transformation of melanocytes. Altered melanin synthesis may also affect the carcinogenesis in malignant melanoma: pheomelanin is increased in malignant melanoma and DMN, but not in normal skin and CMN. Pheomelanin and its precursors could aid the malignant transformation of melanocytes through the generation of mutagenic ultraviolet photoproducts in familial DMN syndrome.

Nikolsky's sign: is it‘dry’ or is it ‘wet’?

Nikolskys sign refers to the ability to induce peripheral extension of a blister as a consequence of applying lateral pressure to the border of an intact blister. Although initially used in reference to the pemphigus group of blistering dermatoses, a positive Nikolskys sign can be seen in other bullous diseases such as toxic epidermal necrolysis and staphylococcal scalded skin syndrome. Appreciating whether the blister is‘wet’or‘dry’at the site of a positive Nikolskys sign may have both diagnostic and prognostic significance which I illustrate with several clinical cases. Lastly, I review the significance of a positive Nikolskys sign.

The dilemma of the dysplastic nevus

There are few areas in dermatology that provoke as much controversy as dysplastic nevus. Over the past decade, there have been significant strides made in terms of understanding the biology and etiology of the lesion. Distinct and reliable clinical and histologic features have been delineated. In this article, the management of patients with dysplastic nevi and the role for dermoscopy, photographic surveillance, genetic mapping and counseling, chemoprevention, and nevi removal are discussed.

Case-control study of melanocytic nevi on the buttocks in atypical mole syndrome : role of solar radiation in the pathogenesis of atypical moles

BACKGROUND It is not known why melanocytic nevi (MN) become dysmorphic (atypical) in patients with the atypical mole syndrome (AMS). A complex origin for acquired MN has been postulated. Genetic predisposition, solar radiation, and/or the formation of a sun-induced circulating mitogenic factor may contribute to the formation of MN. OBJECTIVE This study was undertaken to help elucidate the pathogenesis of atypical MN in patients with AMS. METHODS The number of common and atypical MN was determined for a defined sun-protected area on the buttocks in 150 patients with AMS (cases) and 150 control subjects without AMS. Patients and control subjects were matched for age and sex and were classified into risk groups for the development of malignant melanoma according to the Rigel classification. RESULTS MN on the buttocks were found in 23% of patients with AMS and 9% of control subjects (p < 0.003). In patients versus control subjects the mean number (1.3 vs 1.2, respectively) and mean diameter (5.7 vs 5.9 mm, respectively) of MN on the buttocks did not differ significantly. The MN in both patients and control subjects were not atypical clinically. The odds ratio for having AMS if MN were present on the buttocks was calculated to be 1.56 (95% confidence interval, 1.25 to 1.95). CONCLUSION Although the patients were 2.6 times more likely to have MN on their buttocks than the control subjects, clinically the MN did not differ significantly in number or appearance from those found on the buttocks of control subjects. It is hypothesized that the formation of some atypical MN requires direct solar radiation for their phenotypic expression.

Risk of second primary malignancies following a diagnosis of cutaneous malignant melanoma or nonmelanoma skin cancer in Alberta, Canada from 1979 to 2009

Recent studies have revealed geographical variations with respect to the risk of second primary malignancies (SPMs) following cutaneous malignant melanoma (CMM) and nonmelanoma skin cancer (NMSC).

Epidemiology of dermatofibrosarcoma protuberans in Alberta, Canada, from 1988 to 2007.

BACKGROUND There have only been a few population‐based, epidemiologic studies assessing dermatofibrosarcoma protuberans (DFSP). OBJECTIVE To assess the epidemiology of DFSP in Alberta, Canada, over a 20‐year period. METHODS A population‐based, retrospective analysis of all cases of DFSP in Alberta was conducted using data from the Alberta Cancer Registry. Sex‐, age‐, and anatomical location–specific incidence rates and trends were determined. RESULTS The overall age‐standardized incidence rate of DFSP remained stable at 0.93 per 100,000. DFSP prevalence was highest in individuals aged 20 to 39 (46.8%), followed by those aged 40 to 59 (34.0%), 60 and older (14.7%), and lastly younger than 20 (4.5%). The mean age at diagnosis was 41.1 (women) and 43.1 (men). The incidence of DFSP in men and women has shown a dramatic shift such that incidence in women has increased 3.2% per year, whereas in men it has decreased 2.7% per year. In women, DFSP incidence increased on the trunk and decreased on the upper extremities. CONCLUSION The age‐standardized incidence of DFSP observed is nearly twice as high as previously reported and has remained stable. The incidence is increasing in women and decreasing in men. DFSP primarily affects young to middle‐aged adults and most commonly presents on the trunk.