Differentiation of Basal Cell Carcinoma and Trichoepithelioma: An Immunohistochemical Study.

ABSTRACT: Basal cell carcinoma (BCC) is the most common malignancy of the skin. It is an epithelial neoplasm with origin in the precursor cells of the interfollicular epidermis. Even though it has low metastatic potential, delay in management may lead to local destruction and morbidity. In contrast, trichoepithelioma (TE) is a benign tumor originating from the outer root sheath of the hair follicle. Similar to BCC, TE tends to affect the head and neck region. Both neoplasms may exhibit clinical and histopathological similarities, making them prone to misdiagnosis. Multiple immunomarkers have been used to distinguish among these entities, but so far, no single agent or combination of agents appear to be neither sensitive nor specific enough to differentiate between them. This study was divided into 2 parts. First, 17 cases of BCC and 14 cases of TE were stained with androgen receptor and bcl-2. Then, 27 cases of borderline/equivocal of BCC and 13 cases of borderline/equivocal TE were stained with the same protocol. Sensitivity and specificity were calculated for each individual immunomarker and for the combination of them. Androgen receptor positivity was 100% specific for BCC and borderline/equivocal BCC, whereas bcl-2 diffuse staining pattern demonstrated a sensitivity of 82.4% for BCC and 88.9% borderline/equivocal BCC. When both immunomarkers were combined, the sensitivity for BCC decreased (70.6%) but the specificity remained high (100%). Similarly, the sensitivity for borderline/equivocal BCC was 55.6%, whereas the specificity was 100%. Although moderately sensitive, combining both immunomarkers showed an excellent specificity to discriminate between BCC and TE.

Defining the Histopathological Term Atypical Intraepidermal Melanocytic Proliferation: A Retrospective Cross-Sectional Study.

BACKGROUND: Atypical intraepidermal melanocytic proliferation (AIMP) is a general term assigned to melanocytic proliferations of uncertain biological potential when a definitive histopathological diagnosis cannot be achieved. There are few data available describing the possibility of malignancy of AIMP, or ways to further define diagnosis. OBJECTIVE: To determine the rate of diagnostic change of AIMP to melanoma or melanoma in situ (MIS) after conventional excision. In addition, to determine the role of immunohistochemistry (IHC) in defining AIMP biopsies. METHODS: Retrospective cross-sectional, single-center review of biopsies with a diagnosis of AIMP with a follow-up conventional excision from 2012-2016 was performed. In a separate analysis, a search was performed for AIMP biopsied lesions in which IHC was subsequently performed. RESULTS: The rate of diagnostic change of AIMP to MIS was 4.8% (8/167) after excision. Punch biopsy was a risk factor for diagnostic change to MIS (odds ratio 12.94, confidence interval 2.56-65.38, P = 0.008). The rate of diagnostic change of AIMP biopsies after examining with IHC was 21.3% (34/160) to MIS and 4.4% (7/160) to melanoma. CONCLUSION: The possibility of malignancy of AIMP lesions must be taken into consideration when counseling patients and when planning treatment options. IHC is a useful tool and should be used in the evaluation of AIMP specimens.

Pigmented Lesions of the Nail Unit.

Pigmented lesions of the nail unit are commonly encountered in the clinical setting. Yet, they often present a unique challenge to clinicians because of a broad differential diagnosis or unfamiliarity with clinical and histopathologic features. A wide variety of causes exist ranging from benign lesions such as subungual hemorrhage to malignant lesions such as subungual melanoma. Identifying the underlying cause is key to appropriate management and follow-up in these patients. Although emerging clinical tools such as dermoscopy can be very useful in evaluation of these lesions, histopathologic analysis remains the gold standard. In this review, we discuss and provide a summary of important clinical and histopathological concepts of pigmented lesions of the nail unit with special focus on longitudinal melanonychia, melanotic macule, melanocytic nevus, subungual melanoma, along with discussion of some nonmelanocytic lesions.

Role of Skin Biopsies in the Diagnosis of Hemophagocytic Lymphohistiocytosis.

This is a report of a 15-year-old female who presented with a skin eruption and clinical features consistent with severe sepsis and septic shock. A diagnosis of acquired hemophagocytic lymphohistiocytosis (HLH) was made and confirmed by bone marrow analysis. Skin biopsy showed hemophagocytosis and CD163-positive staining of macrophages. We briefly review the clinical, histologic, and laboratory findings of hemophagocytic lymphohistiocytosis in addition to the potential role of skin biopsies in this condition.

Palisaded Granuloma on the Nose: An Atypical Presentation of Granuloma Annulare.

Granuloma annulare (GA) is a common, asymptomatic dermatosis of unknown etiology. Many variants exist, among them widespread papules, papules in photodistribution, papules marked by tiny crusts ("perforating" GA), patches, plaques, and nodules (subcutaneous GA). The histopathological hallmark is a palisaded histiocytic infiltrate surrounding a central area of degenerated collagen with abundant mucin deposits. We report 2 women who presented with persistent nodules on the nose, which, on histopathological examination, showed a palisaded granuloma. We propose that these cases represent an unusual variant of GA occurring on the nose.

Extraocular Sebaceous Carcinoma-A Clinicopathologic Reassessment.

Sebaceous carcinoma is an aggressive adnexal neoplasm with sebaceous differentiation. Few reports have described the histopathologic characteristics of the sebaceous carcinoma occurring extraocularly. Seventy-two cases of extraocular sebaceous carcinoma were identified from the database of a Dermatopathology Laboratory from January 1, 2007 to May 31, 2013. More cases occurred in men (60%), with a mean age at diagnosis of 65.8 years (range 39-99 years). Neoplasms were histopathologically classified as well-differentiated (22%), moderately differentiated (67%), and poorly differentiated (11%). Sixty-seven percent (67%) of cases demonstrated a squamoid growth pattern and thirty-three percent (33%) demonstrated a basaloid growth pattern. A majority of the neoplasms histopathologically classified as well-differentiated (94%) and moderately differentiated (65%) demonstrated a squamoid growth pattern. Ten percent (10%) of cases exhibited cystic histopathologic changes. The histopathological features reported in this study aid in the understanding of extraocular sebaceous carcinoma and its eventual diagnosis and classification.

Impacto educativo de una evaluación basada en el desempeño en residentes de medicina del Programa de Segunda Especialización de la Universidad Privada Antenor Orrego, Trujillo, Perú / Educational impact of a performance based evaluation in residents of the Program of Second Specialization in medicine at the Antenor Orrego Private University, Trujillo, Peru

Objetivo: Determinar el impacto de la evaluación basada en el desempeño de los residentes utilizando el modelo de Kirkpatrick. Sujetos y métodos: Estudio descriptivo tipo encuesta a 93 residentes (72 de primer año y 21 de segundo año) y 34 tutores del Programa de Segunda Especialización de la Universidad Privada Antenor Orrego. Se consideró una actitud positiva cuando los encuestados calificaron un ítem con una media igual o superior a 4 en una escala Likert de cinco puntos para los niveles de Kirkpatrick 1 a 3, y el nivel 4 se midió evaluando las tasas de mortalidad neta e infecciones intrahospitalarias en cinco hospitales académicos de Trujillo, Perú, entre los años 2012-2014. Resultados: La discusión de casos clínicos e incidentes críticos y la retroalimentación del portafolio virtual tuvieron un impacto positivo en los residentes en los niveles 1 a 3 de Kirkpatrick. Los tutores consideraron que las pruebas de progreso, portafolio, ejercicio de evaluación miniclínico (mini-CEX) y observación directa de actividades procedimentales (DOPS) tuvieron un efecto positivo en el desempeño de los residentes en los niveles 1 a 3 de Kirkpatrick. La evaluación tuvo impacto positivo en el nivel 4. Conclusiones: Se debe enfatizar la discusión de casos clínicos e incidentes críticos y retroalimentación del portafolio virtual y, en general, la evaluación basada en el desempeño de los residentes tendría impacto en el nivel 4 de Kirkpatrick al mejorar la mortalidad neta e infecciones intrahospitalarias en hospitales académicos

Aim: To investigate the impact of formative and reflective assessment on performance of residents according the Kirkpatrick’s model. Subjects and methods: Cross-sectional study in which a survey was to sent to 93 residents (first year, 72; second year, 21) and 34 mentors of the Program of Second Specialization at the Antenor Orrego Private University. Each item was rated on a Likert scale of five points, and was considered relevant when respondents rated an item with an equal or higher average score of 4 (which indicated a positive attitude) and level 4 was evaluated considering net mortality and intrahospitalary rates in five academic hospitals in Trujillo, Peru, among 2012 and 2014. Results: The components of the corresponding portfolio to reflective and critical incidents and discussion of clinical cases obtained educational impact on levels 1, 2 and 3 in residents. Clinical mentors felt that progress tests, portfolios, MiniClinical Evaluation Exercise (Mini-CEX) and Direct Observation of Procedural Skill (DOPS) had a positive effect on the performance of residents in levels 1, 2 and 3 of Kirkpatrick. The assessment system had impact on the level 4 of Kirkpatrick. Conclusions. It should encourage case-based discussion, reflective critical incidents and feedback components of virtual portfolio in order to improve the performance of residents and performance-based evaluation would have a positive impact in the level 4 of Kirkpatrick in reducing the rates of net mortality and nosocomial infections in academic hospitals

Clear-Cell Atypical Fibroxanthoma: A Combined Immunohistochemistry Analysis.

Atypical fibroxanthoma is considered to be a low-grade sarcoma, characterized by a proliferation of bizarre spindled cells. A case of a rare variant of this tumor, a clear-cell atypical fibroxanthoma, presenting with rapid growth on a 63-year-old female, is reported. The differential diagnosis of a clear cell proliferation and a review of the immunohistochemistry markers used in the diagnosis of atypical fibroxanthoma are discussed. In particular, the usefulness of markers such as CD10, procollagen 1, CD68, CD163, CD99, and S100A6, and the importance of negative markers such as S100, cytokeratin, and desmin are emphasized. Furthermore, the development of a keratoacanthoma at the site of previous Mohs surgery is recounted.

Acquired segmental neuromas.

Neuromas are benign hyperplastic proliferations of normal peripheral nerve components. These can be associated with some genodermatoses, namely Cowden syndrome and multiple endocrine neoplasia (MEN) 2B, especially when numerous lesions are present. Given the potential for malignancy (such as breast cancer, pheochromocytoma, and thyroid cancer) associated with these syndromes, other features indicative of either syndrome should be evaluated in patients presenting with multiple cutaneous neuromas. The evaluation should include a thorough family history and complete physical, dermatologic, and ophthalmologic exams as well as thyroid studies. We report, herein, the case of an 8-year-old female with cutaneous neuromas distributed segmentally with no other associated finding suggestive of an underlying syndrome.

Acquired acrodermatitis enteropathica: case report of an atypical presentation.

Acrodermatitis enteropathica (ADE) is a rare genetic or acquired disorder of hypozincemia. It can be caused by impaired intestinal absorption of zinc or by poor consumption of the mineral. It is characterized by skin lesions on acral and periorificial areas and may be associated to alopecia, diarrhea and increased frequency of infections. We present an atypical presentation of ADE in a 33-year-old women with a history of mental retardation and psoriasis that presented with lesions on the periorificial areas and extremities, and low plasma zinc levels.