Bilateral accessory axillary breast tissue in a premenarchal female.

A 9-year-old premenarchal female presented to pediatric dermatology with a 6-month history of periodically tender, bilateral and symmetric axillary masses. Magnetic resonance imaging and subsequent surgical excision confirmed the diagnosis of bilateral accessory axillary breast tissue. Accessory axillary breast tissue is a rare condition seen most in pubertal, pregnant and breastfeeding women. However, it can arise in pre-adolescent patients and should be added to the differential diagnosis of an axillary mass.

Determining the Association Between Melanomas and Fields of Melanocytic Dysplasia.

ABSTRACT: Some have proposed that melanomas in situ may be associated with fields of melanocytic dysplasia, particularly on sun-damaged skin, whereas others maintain that the atypical junctional melanocytic hyperplasia (MH) at the periphery of melanomas is simply background junctional MH of sun-damaged skin. The biological potential of atypical junctional MH at the periphery of melanomas is uncertain. We examined whether atypical junctional MH was intrinsic to the melanoma itself (ie, melanoma-associated field of melanocytic dysplasia) or was simply the predictable junctional MH associated with long-standing sun exposure. We retrospectively compared 106 cutaneous melanoma excisions without residual tumor with 105 nonmelanoma cutaneous tumor excisions (ie, basal cell or squamous cell carcinomas) without residual tumor. MH with atypia occurred significantly more frequently in melanoma than in nonmelanoma cutaneous tumor excisions (55.7% vs. 24.8%, P < 0.001). Solar elastosis occurred significantly less frequently in melanoma than in nonmelanoma cutaneous tumor excisions; 33.0% of melanoma excisions and 8.6% of nonmelanoma excision samples exhibited no solar elastosis, respectively (P < 0.001). After controlling for solar elastosis using multivariable linear regression, the association between MH with atypia and melanoma excisions remained significant (P < 0.001). Our results, therefore, demonstrate that melanomas were associated with atypical junctional MH that could not solely be accounted for by the extent of sun damage as measured by solar elastosis.

Whole-Exome Sequencing of a Case of Squamoid Eccrine Ductal Carcinoma Reveal Similarities With Cutaneous Squamous Cell Carcinoma.

ABSTRACT: Squamoid eccrine ductal carcinoma (SEDC) is a poorly documented but likely underrecognized sweat gland malignancy with significant risk for local recurrence and potential for metastasis and rare disease-related mortality. Histopathologically, the tumor demonstrates a biphasic differentiation pattern: superficially, the tumor has squamous differentiation [indistinguishable from well-differentiated cutaneous squamous cell carcinoma (cSCC)], while the deeper aspect has a more infiltrative pattern with prominent ductal differentiation. Diagnosis of SEDC relies upon histopathologic examination alone. Its pathogenesis is poorly understood, and its genomic features have yet to be described. In this article, we characterize the genomic features in a case of SEDC through whole-exome sequencing, then compare its features with cSCC and other eccrine ductal carcinomas. Whole-exome sequencing revealed 30 mutations/Mb with 21 pathogenic or likely pathogenic mutations in total, identified across 14 different genes. The genomic abnormalities identified in this case of SEDC overlap considerably with those found in cSCC but not those of other sweat gland malignancies. The clinical and histopathologic features of SEDC previously reported and the genetic features determined from this case suggest that this tumor may arise initially as a well-differentiated cSCC that subsequently undergoes divergent differentiation focally to resemble a sweat gland malignancy. Genetic analyses of additional cases are warranted to clarify this consideration.

Comparing Follicular Extension Between Low-Grade and High-Grade Dysplastic Nevi.

ABSTRACT: Dysplastic nevi are an important subset of melanocytic nevi with atypical clinical, histopathologic, as well as genomic features compared with common acquired nevi. Dysplastic nevi are characterized histologically by both cytologic atypia and architectural disorder. The established criteria for cytologic atypia used to distinguish between low-grade and high-grade dysplastic nevi are often subjective, although there is a dearth of more objective, reproducible features of architectural disorder (eg, pagetoid scatter) that have been validated to differentiate between low-grade and high-grade dysplastic nevi. In this study, we sought to determine whether the presence and degree of follicular extension differ between low-grade and high-grade dysplastic nevi. We retrospectively examined the histopathologic features of 90 dysplastic nevi: 60 cases of low-grade dysplastic nevi (average age of 47.2 ± 18.1 years; 62.7% female) and 30 cases of high-grade dysplastic nevi (average age of 47.4 ± 19.8 years; 60.0% female). After examination, 50% of the cases of dysplastic nevi (n = 45) had hair follicles within the lesion, for which the presence and degree of follicular extension was then determined. Low-grade and high-grade dysplastic nevi do not differ significantly regarding the presence of follicular extension, average depth of follicular extension, and confluence of nevus cells along the follicular epithelium. Both low-grade and high-grade dysplastic nevi in our study demonstrated follicular extension that was superficial, that is, above the level of isthmus of hair follicles (insertion of sebaceous gland into hair follicle). Future studies are warranted to confirm these preliminary findings.

Sporadic superficial angiomyxomas demonstrate loss of PRKAR1A expression.

Superficial angiomyxomas are cutaneous mesenchymal tumours that typically present clinically as slow-growing, solitary, asymptomatic nodules that can occur at any age. Histopathologically, these dermal and subcutaneous tumours are characterized by abundant myxoid stroma, numerous thin-walled and often arbourising blood vessels, and spindled to stellate fibroblast-like cells. While usually sporadic, superficial angiomyxomas can occasionally be associated with Carney complex (CNC), an autosomal dominant disorder characterized by inactivating germline mutations in the 1-alpha regulatory subunit of protein kinase A (PRKAR1A) and various clinical manifestations, including cardiac myxomas, facial lentigines, epithelioid blue naevi, endocrinopathies and psammomatous melanotic schwannomas. In this study, we sought to characterize the presence or absence of PRKAR1A expression by immunohistochemistry (IHC) in sporadic superficial angiomyxomas based on our observations in an index case. In total, PRKAR1A immunohistochemical expression was determined in 15 sporadic superficial angiomyxoma cases retrieved from the surgical pathology archives. IHC demonstrated that the lesional cells in 12 cases (80%) were non-reactive to antibodies against PRKAR1A. This study provides evidence in support of a role for PRKAR1A in the development of clinically non-syndromic superficial angiomyxomas. Together with previous studies, this report demonstrates that PRKAR1A may play an important role in the development of a variety of myxomatous mesenchymal tumours.

Advanced basal cell carcinoma: What dermatologists need to know about diagnosis.

Basal cell carcinoma (BCC) is the most common human cancer, with approximately 3.6 million cases diagnosed each year. About 2000 deaths annually in the United States are attributed to basal and squamous cell skin cancers. There is a direct link between ultraviolet exposure and the development of BCC, as UV exposure damages DNA and induces mutations in tumor suppressor genes. Aberrations in the hedgehog pathway can also result in BCC, highlighted by the fact that most cases of sporadic BCCs have been found to have mutations in different genes involved in the hedgehog pathway. There are several genetic syndromes that are associated with BCCs, including basal cell nevus syndrome, xeroderma pigmentosum, Bazex-Dupré-Christol syndrome, Rombo syndrome, and Oley syndrome. Other risk factors include age, male gender, occupational hazards, radiation, and immunosuppression. BCCs are not typically staged but are instead stratified by their risk of recurring or metastasizing. Locally advanced BCCs are those tumors that are not amenable to surgery or radiation therapy.

Acquired Reactive Perforating Collagenosis Occurring in Association With Nonred Ink Tattoo.

ABSTRACT: Perforating dermatosis is a group of skin conditions in which there is transdermal elimination of collagen, elastic fibers, or other dermal connective tissue. Perforating dermatosis can be genetic or acquired, known as acquired perforating dermatosis (APD). When collagen is the primary extruded material in acquired cases, the disease is designated as acquired reactive perforating collagenosis (RPC). We report a case of acquired RPC occurring in a new tattoo. One week after having a new tattoo placed on the left forearm, a 38-year-old gentleman presented to the emergency room with pruritic, crusted plaques and erosions in the regions of red and green inks of the tattoo. Histopathologic examination of the biopsy revealed an ulceration with transepidermal elimination of collagen bundles accompanied by basophilic debris, scattered dermal tattoo pigment, and a superficial to deep perivascular lymphohistiocytic infiltrate with scattered neutrophils and eosinophils. There have been 2 reported cases of tattoo-associated RPC, both in association with red tattoo ink. This present case is the first reported APD to occur in association with nonred tattoo ink. This case reaffirms the conclusions of others in recognizing APD as a potential tattoo-associated complication.

Intralesional corticosteroid injections to treat lip swelling associated with oral Crohn's disease in a child.

This procedural report details the case of a 10-year-old boy with oral Crohn's disease successfully treated with intralesional corticosteroid injections. The intervention used topical anesthesia with a eutectic mixture of lidocaine 2.5%/prilocaine 2.5% cream followed by intralesional triamcinolone acetonide. This approach safely and effectively reduced patient discomfort while allowing for an acceptable and durable clinical outcome.

Leukemia Cutis With Histopathologic and Immunophenotypic Features Resembling S100-Negative CD1a-Positive Cutaneous Histiocytosis.

ABSTRACT: S100-negative CD1a-positive cutaneous histiocytosis is an exceedingly rare histiocytosis that is defined histopathologically by a dense dermal infiltrate of ovoid mononuclear cells with grooved nuclei and ample cytoplasm with variable nuclear atypia and mitoses that are immunohistochemically positive for CD1a and negative for S100 and CD207 (langerin). The histogenesis of S100-negative CD1a-positive histiocytosis is unclear, and its precursor cell has yet to be characterized. Although all cases thus far have been described as benign and occasionally self-resolving, the clinical course and outcome of this disease are not fully understood. This case expands the spectrum of disease associated with S100-negative CD1a-positive histiocytosis given its malignant course.

Imported fire ant envenomation: A clinicopathologic study of a recognizable form of arthropod assault reaction.

BACKGROUND: Skin reactions to the sting of the imported fire ant have characteristic clinicopathological features. METHODS: One case of experimental envenomation was prospectively followed during 48 hours, with biopsies. In addition, 6 cases from our laboratory were retrospectively evaluated histopathologically for the following features: spongiosis, exocytosis (and type of cells), pustule formation, erosion/ulceration, epidermal necrosis, scale/crust, papillary dermal edema, inflammatory dermal infiltrate (cell type, density, depth, distribution, shape), red blood cell extravasation, vasculopathy and vasculitis. RESULTS: The typical lesion follows a very distinctive clinical and histopathologic evolution over 48 hours, with the formation of a subepidermal pustule overlying a wedge-shaped area of dermal collagen basophilic degeneration with scattered neutrophils. In the 6 cases retrieved from our files, the main features were a superficial and deep dermal, perivascular, periadnexal and interstitial infiltrate consisting of neutrophils, with basophilic degeneration of the collagen. A subepidermal pustule was noted in half of the cases. CONCLUSIONS: In biopsies taken in a clinical setting, even in the absence of the characteristic subepidermal pustule, the diagnosis of imported fire ant sting can be suspected if there is a superficial and deep perivascular, periadnexal and interstitial infiltrate composed of neutrophils, with some basophilic denaturation of collagen.

Stratum corneum reservoir as a predictive method for in vitro percutaneous absorption.

Interaction between drug and proteins and lipids in stratum corneum (SC) is an important pharmacokinetic parameter in early steps of absorption. Previous in vivo studies showed that the total amount of compound, regardless of properties, penetrating over a 96 h period could be predicted by the amount present in SC 30 min after application by a linear relationship. Validating this linear relationship through in vitro study would facilitate testing of transdermal drug delivery platforms. We aimed to determine in vitro penetration behavior across SC of humans by determining the relationship between quantity present in SC reservoir 30 min after application with 24 h skin absorption and penetration. In this study, use of the SC reservoir effect to predict absorption and penetration of topical compounds is reaffirmed with in vitro models involving human skin. These results indicate the amount in short-term (30 min) SC reservoir predict long-term (24 h) skin absorption and penetration, as characterized by statistically significant linear relationships determined via regression. This may be explained by the fact that SC is a rate-limiting barrier to percutaneous drug transport. After molecules diffuse through SC barrier, passage into deeper dermal layers and systemic uptake occur relatively quickly. These results enable one to measure quantity in SC reservoir shortly after topical application as a proxy for absorption and penetration over longer periods. With respect to drug development and risk assessment of toxic substances, this may simplify assays attempting to quantitate penetration capacity. Further investigation with a larger range of compounds is needed to clarify the observations recorded here. Copyright © 2015 John Wiley & Sons, Ltd.

Laser and light therapies for the treatment of nail psoriasis.

Psoriatic involvement of the nail is notoriously refractory to conventional therapy. Nail psoriasis has a high incidence amongst patients with psoriasis. It remains a significant cosmetic problem and thus, has a significant impact on quality of life. More recently, light and laser therapies have emerged as modalities for treatment of nail psoriasis. In this study, the efficacies of light and laser therapies are systematically reviewed. Light therapies involve ultraviolet light (with or without photosensitizers) or intense pulsed light. Alternatively, laser therapy in nail psoriasis is primarily administered using a 595-nm pulsed dye laser. These modalities have demonstrated significant improvement in psoriatic nail lesions, and even complete resolution in some cases. Both laser and light modalities have also been tested in combination with other systemic or topical therapeutics, with variable improvement in efficacy. Both laser and light therapies are generally well tolerated. Side-effects of light therapies include hyperpigmentation, itching and erythema; whereas, side-effects of laser therapy are more frequent and include pain, purpura/petechiae and hyperpigmentation. Patterns of response to therapy were also seen based on presenting characteristics of the nail lesions: subungual hyperkeratosis and onycholysis appeared to be the most responsive to therapy, while nail pitting was the most resistant. Light or laser therapies have the potential to be an efficient and cost-effective in-office based treatment for nail psoriasis. However, more large-scale clinical trials are needed to assess their efficacy, particularly in combination with other therapeutic modalities.