Trichoepithelioma is a benign neoplasm that shares both clinical and histological features with basal cell carcinoma. It is important to distinguish these neoplasms because they require different clinical behavior and therapeutic planning. Many studies have addressed the use of immunohistochemistry to improve the differential diagnosis of these tumors. These studies present conflicting results when addressing the same markers, probably owing to the small number of basaloid tumors that comprised their studies, which generally did not exceed 50 cases. We built a tissue microarray with 162 trichoepithelioma and 328 basal cell carcinoma biopsies and tested a panel of immune markers composed of CD34, CD10, epithelial membrane antigen, Bcl-2, cytokeratins 15 and 20 and D2-40. The results were analyzed using multiple linear and logistic regression models. This analysis revealed a model that could differentiate trichoepithelioma from basal cell carcinoma in 36% of the cases. The panel of immunohistochemical markers required to differentiate between these tumors was composed of CD10, cytokeratin 15, cytokeratin 20 and D2-40. The results obtained in this work were generated from a large number of biopsies and resulted in the confirmation of overlapping epithelial and stromal immunohistochemical profiles from these basaloid tumors. The results also corroborate the point of view that trichoepithelioma and basal cell carcinoma tumors represent two different points in the differentiation of a single cell type. Despite the use of panels of immune markers, histopathological criteria associated with clinical data certainly remain the best guideline for the differential diagnosis of trichoepithelioma and basal cell carcinoma.

Cutis verticis gyrata is characterized by excessive formation of scalp skin. It may be primary (essential and nonessential) or secondary. In the primary essential form it presents only folding skin formation on the scalp, mimicking cerebral gyri, without associated comorbidities. We report a rare case of a 28 year-old male patient with primary essential cutis verticis gyrata.

Quinze deles foram submetidos à técnica em W-plastia e 17, à técnica clássica. Avaliaram-se parâmetros como retração cicatricial e alterações funcionais. RESULTADOS: Houve associação estatisticamente significativa entre a técnica utilizada e a presença de retração cicatricial, sendo a associação positiva com a clássica (p=0,01 com correção de Yates). O risco relativo (odds ratio -OR) calculado foi de 11,25, ou seja, houve maior chance de retração nos pacientes submetidos à técnica clássica. Nenhuma das técnicas apresentou alterações funcionais. Avaliaram-se complicações pós-operatórias como presença de crostas, lábios secos, parestesia e deiscência de sutura. Não houve associação estatisticamente significante entre as complicações e a técnica utilizada (p=0,69). CONCLUSÃO: Concluiu-se que a vermelhectomia em W-plastia oferece melhores resultados estéticos e índices de complicações semelhantes.

This case report details how melphalan and prednisone can be administered in the successful treatment of necrobiotic xanthogranuloma with lambda paraproteinemia.

Trichilemmoma is a benign neoplasm from the outer sheath of the pilosebaceous follicle. Desmoplastic trichilemmoma, a rare variant, is histologically characterized by a central area of desmoplasia that can clinically mimic an invasive carcinoma, requiring histopathological examination to define the diagnosis.

Linear immunoglobulin A dermatosis is a rare autoimmune bullous disease, but the most common autoimmune bullous dermatosis in children. We report a typical exuberant case of linear IgA dermatosis in a ten-month old child, who showed good response to treatment with corticosteroids and dapsone.

Severe cutaneous drug reactions include a wide spectrum of clinical manifestations ranging from mild morbilliform cutaneous rash, to severe forms of hypersensitivity. Special attention is given in this report to the acute generalized exanthematous pustulosis (AGEP), induced in 90% of cases by the use of systemic drugs, especially aminopenicillins and macrolides. The incidence of the disease is low, 1-5 cases per million patients / year. The main differential diagnosis is Von Zumbusch's Pustular Psoriasis. The prognosis is generally good and the disease self limited, after withdrawal of the triggering drug. In this report the authors describe a case of AGEP, triggered by ceftriaxone in a patient with psoriasis vulgaris.

Traumatic neuromas are tumors resulting from hyperplasia of axons and nerve sheath cells after section or injury to the nervous tissue1. We present a case of this tumor, confirmed by anatomopathological examination, in a male patient with history of circumcision. Knowledge of this entity is very important in achieving the differential diagnosis with other lesions that affect the genital area such as condyloma acuminata, bowenoid papulosis, lichen nitidus, sebaceous gland hyperplasia, achrochordon and pearly penile papules.