American Journal of Dermatopathology最新文献

Abstract: Cutaneous ciliated cysts are rare benign lesions most commonly seen in the lower extremities of young female patients. There is still ongoing debate about the origin of these cysts, with the most common theories being Mullerian heterotopia and eccrine gland metaplasia. To further increase the data pool, we present 2 new cutaneous ciliated cyst cases and gathered data about all 67 cases of literature. We want to highlight that immunohistochemistry and demographic information may play a key role in distinguishing between the 2 possible origins of this cyst, namely estrogen receptor, progesterone receptor, and carcinoembryonic antigen immunohistochemistry. Estrogen receptor and progesterone receptor nuclear positivity is proof of Mullerian origin, but when they are negative with a positive carcinoembryonic antigen, the most likely origin is eccrine gland metaplasia. We advocate using the terms "Cutaneous Mullerian Cyst" and "Ciliated Cutaneous Eccrine Cyst" instead of "Cutaneous Ciliated Cyst" to accurately indicate their distinct origins.

Background: Being one of the largest dermatology groups in the country with an in-house pathology laboratory, we have seen a significant increase in the number of adhesive-based pigmented lesion assays (ABPLAs) in addition to biopsies and excisions following a moderate-risk or high-risk result with this test.

Objective: To report our clinical experience and independently confirm that our results with this ABPLA (Pigmented lesion assay, DermTech. San Diego, CA) are consistent with the results of the validation studies completed by the test manufacturer.

Methods: A retrospective review of our electronic medical records for results of ABPLAs, corresponding histopathologic results and available clinical follow-up, along with their statistical analysis was completed.

Results: After reviewing our electronic medical records, we found that 893 ABPLAs for pigmented lesions concerning for melanoma were obtained in a period of 14 months. Of the 893 ABPLAs completed, 161 biopsies and excisions were performed after the initial results of these assays. Additional clinical follow-up data were recorded and used for the statistical analysis of the performance and accuracy of this test.

Limitations: The small number of lesions reported as low risk for melanoma with corresponding histopathologic results limits our evaluation of the performance of this test. In addition, there may have been some melanomas that were not identified because the duration of the clinical follow-up was insufficient or because some patients were lost to follow-up.

Conclusion: In our experience this ABPLA has a sensitivity of 92.0%, a specificity of 79.5%, a positive predictive value of 16.9%, and a negative predictive value of 99.5% for the detection of melanoma.

Abstract: Rhinophyma is the advanced stage of rosacea and manifests clinically with disfigurement of the nose. The histopathology has been classified into classical and severe types. We studied the clinicopathological characteristics of 8 cases with the diagnosis of rhinophyma. In 5 of 9 specimens, floret-like multinucleated giant cells containing lipid were identified. This finding, to the best of our knowledge, has not been previously described.

Abstract: Merkel cell carcinoma (MCC) is known as a rare and highly malignant neuroendocrine skin cancer and often occurs in the sun-exposed parts of the elderly individuals. In this article, we reported 2 cases of MCC and reviewed relative literature. Case 1 was a 91-year-old woman who presented with a half-year history of a brown nodule on the left temple. The histopathological and immunohistochemistry examination diagnosis was MCC with negative staining of Merkel cell polyomavirus large T antigen (CM2B4). Case 2 was a 76-year-old man with a nodule on his right buttock that gradually increased from approximately 3 mm to 1.5 cm in diameter in 1 month without pain. The biopsy diagnosis was MCC with positive staining of CM2B4. Previous studies have found that the genetic mutation and prognosis of polyomavirus-associated MCC (MCCP) and nonviral MCC (MCCN) are significantly different. Large T antigen plays a crucial role in Merkel cell polyomavirus (MCPyV) oncogenesis. Testing for the MCPyV at the onset of MCC is recommended, which is helpful in predicting the prognosis of patients.

Abstract: Plasmacytoid dendritic cell neoplasms are rare neoplasms originating from plasmacytoid dendritic cells (pDCs). They are subclassified into 2 types: blastic plasmacytoid dendritic cell neoplasm and mature plasmacytoid dendritic cell proliferation. Neoplastic expansion of pDCs has also been found to be associated with myeloid neoplasia. We present the diagnostically challenging case of a 62-year-old woman who presented to the emergency department with numerous hemorrhagic nodules and papules on the face and extensor surfaces near the elbows and neutropenic fevers. The patient had a history notable for lupus erythematosus and a recently performed excisional lymph node biopsy involved by a "plasmacytoid dendritic cell proliferation." A punch biopsy was performed, which showed a robust dermal infiltrate of atypical intermediate-sized mononuclear cells. The infiltrate was positive for CD4, CD43, and CD123. CD3 and CD8 highlighted background T cells. The infiltrate was negative for CD10, CD34, CD56, CD68, CD117, myeloperoxidase, lysozyme, TdT, and TCL-1. The findings favored a diagnosis of cutaneous involvement of the plasmacytoid dendritic cell proliferation. Given the association with acute leukemias, a subsequent bone marrow biopsy was recommended. The bone marrow biopsy was performed, which showed increased blasts (68% on a 500 differential cell count). Furthermore, immunohistochemical stains were performed, which highlighted the blasts to be positive for CD34 and BEST (alpha-naphthyl butyrate esterase) cytochemical stain. This diagnosis was consistent with bone marrow involvement of acute myelomonocytic leukemia. Given the overlapping presenting symptoms (skin lesions, adenopathy, marrow involvement) of pDC neoplasms and myeloid neoplasia and the possibility of presenting concurrently, increased awareness is of pivotal importance to help prevent potential misdiagnosis, missed diagnosis, and prompt investigation of possible associated neoplasms.

Abstract: Lymphomatoid papulosis (LyP) belongs to the CD30 + skin lymphoproliferative disorders; it is defined as a chronic, recurrent, self-healing eruption of papules and small nodules with the histopathologic features of a cutaneous T-cell lymphoma. It is classified according to histopathology into subtypes A to F and with chromosomal rearrangement 6p25.3. Type D is characterized by epidermotropism of atypical CD8 + and CD30 + lymphocytes, small to medium size, forming papules and nodules with erosion and necrosis, which represents a formidable challenge in the differential diagnosis with aggressive cutaneous cytotoxic lymphomas. We present the clinical case of a 22-year-old man with subacute dermatosis, who underwent a skin biopsy with a report of LyP. Immunohistochemistry showed negative CD4, CD5, granzyme-B markers and positive CD3, CD30, CD8, CD56, and (T-cell intracellular antigen 1) TIA-1 markers, concluding the diagnosis of type D LyP. The course of the disease is recurrent; however, the prognosis is good with a 10-year survival of 100%. We present the case of a mestizo-ancestry patient who developed a type-D LyP, and, to the best of our knowledge, there are no publications of type D LyP from Latin-American authors or about mestizo-ancestry (or hispanic) patients; therefore, we consider of relevance to inform about these findings.

Abstract: Bullous lupus erythematosus (BLE) and linear IgA disease (LAD) are rare autoimmune subepidermal blistering diseases, with overlapping features despite different pathogenetic mechanisms. Diagnosis is based on immunofluorescence and serology. This retrospective study was undertaken to compare the histopathologic features of BLE and LAD (11 cases each). The mean age was 36 years in both groups, and female preponderance was noted in BLE. Clinically, all cases presented as tense, itchy blisters distributed over the trunk, face, and extremities. Subepidermal neutrophil-rich blisters were seen in 60% BLE and 54.54% LAD cases. Eosinophils in the blisters were noted in 4 cases (36.4%) of linear IgA bullous dermatosis, but not in any of the BLE cases. The adjacent epidermal changes noted include spongiosis (33%; 40%), papillary microabscesses (22%; 20%), and basal tagging by neutrophils (77%; 70%). Superficial perivascular inflammation was seen in all cases while deep perivascular inflammation was observed in 54% BLE and 36% LAD cases. Lymphocytes were the predominant infiltrate. Increased dermal mucin was seen in 60% BLE and 45% LAD cases. None of the histopathologic features showed a statistically significant difference between the 2 groups. Hence, histopathology alone is of limited value in distinguishing the 2 groups. Diagnosis rests on immunofluorescence and serologic findings, which should be used even in cases that seem to be classic LAD or patients without history of systemic lupus erythematosus.