Stephen H. Olsen

Netting Neutrophils Induce Endothelial Damage, Infiltrate Tissues, and Expose Immunostimulatory Molecules in Systemic Lupus Erythematosus

An abnormal neutrophil subset has been identified in the PBMC fractions from lupus patients. We have proposed that these low-density granulocytes (LDGs) play an important role in lupus pathogenesis by damaging endothelial cells and synthesizing increased levels of proinflammatory cytokines and type I IFNs. To directly establish LDGs as a distinct neutrophil subset, their gene array profiles were compared with those of autologous normal-density neutrophils and control neutrophils. LDGs significantly overexpress mRNA of various immunostimulatory bactericidal proteins and alarmins, relative to lupus and control neutrophils. In contrast, gene profiles of lupus normal-density neutrophils do not differ from those of controls. LDGs have heightened capacity to synthesize neutrophils extracellular traps (NETs), which display increased externalization of bactericidal, immunostimulatory proteins, and autoantigens, including LL-37, IL-17, and dsDNA. Through NETosis, LDGs have increased capacity to kill endothelial cells and to stimulate IFN-α synthesis by plasmacytoid dendritic cells. Affected skin and kidneys from lupus patients are infiltrated by netting neutrophils, which expose LL-37 and dsDNA. Tissue NETosis is associated with increased anti-dsDNA in sera. These results expand the potential pathogenic roles of aberrant lupus neutrophils and suggest that dysregulation of NET formation and its subsequent responses may play a prominent deleterious role.

Elafin is a biomarker of graft-versus-host disease of the skin.

Plasma elafin concentrations correlate with graft-versus-host disease of the skin and long-term survival. Progress toward biomarker commercialization requires the discovery, qualification, verification, optimization, and clinical validation of a candidate before it is incorporated into existing therapeutic diagnostic platforms. The tremendous value that could be derived from the advancement of methods to detect disease at earlier and more treatable stages puts this pipeline approach at the forefront of biomarker development. However, to date there are no clear success stories in which discovery proteomics has led to a deployed protein biomarker. There is no polymerase chain reaction equivalent available to detect, quantify, and amplify proteins. Rather, proteomics-based biomarker discovery across a wide assortment of diseases is enabled by technologies such as mass spectrometry to sift through a large span of complex analytes at variable concentrations. Now, Paczesny and colleagues use a mass spectrometry–based technique to unambiguously identify candidate plasma biomarkers of skin acute graft-versus-host disease (GVHD)—the primary cause of nonrelapse mortality after bone marrow transplantation (BMT). Rashes are common after BMT and can be caused by a variety of reasons, but because the consequences of GVHD are serious, physicians initiate treatment of suspected GVHD without a bona fide confirmed diagnosis. In the discovery set of this work, the authors examined plasma samples from patients who had received BMT with and without clinical diagnosis of skin GVHD, and found that in patients with skin GVHD, the concentration of one lead marker, elafin, was three times as high. In a follow-up independent validation of 492 BMT patients, skin biopsies stained with elafin stratified the patients consistently according to GVHD parameters, and elafin plasma concentrations were concordantly higher in patients with GVHD. The specificity and sensitivity of elafin relative to other markers revealed that it was the single best discriminator for the diagnosis of GVHD in BMT patients with a rash, and was correlated with the severity of the disease. Elafin concentrations also correlated with the eventual maximum grade of GVHD and with nonrelapse mortality. These results show that elafin concentrations may serve as a noninvasive diagnostic test as well as a prognostic marker in determining GVHD grading in the clinic. Graft-versus-host disease (GVHD), the major complication of allogeneic bone marrow transplantation, affects the skin, liver, and gastrointestinal tract. There are no plasma biomarkers specific for any acute GVHD target organ. We used a large-scale quantitative proteomic discovery procedure to identify biomarker candidates of skin GVHD and validated the lead candidate, elafin, with enzyme-linked immunosorbent assay in samples from 492 patients. Elafin was overexpressed in GVHD skin biopsies. Plasma concentrations of elafin were significantly higher at the onset of skin GVHD, correlated with the eventual maximum grade of GVHD, and were associated with a greater risk of death relative to other known risk factors (hazard ratio, 1.78). We conclude that elafin has significant diagnostic and prognostic value as a biomarker of skin GVHD.

Cluster analysis of immunohistochemical profiles in synovial sarcoma, malignant peripheral nerve sheath tumor, and Ewing sarcoma

As a result of overlapping morphologic and immunohistochemical features, it can be difficult to distinguish synovial sarcoma, malignant peripheral nerve sheath tumor, and Ewing sarcoma/primitive neuroectodermal tumor in core biopsies. To analyze and compare immunohistochemical profiles, we stained tissue microarrays of 23 synovial sarcomas, 23 malignant peripheral nerve sheath tumors, and 27 Ewing sarcomas with 22 antibodies potentially useful in the differential diagnosis, and analyzed the data with cluster analysis. Stain intensity was scored as none, weak, or strong. For CD99, tumors with membranous accentuation were independently categorized. Cluster analysis sorted five groups, with like tumors clustering together. Synovial sarcoma clustered into two groups: one cytokeratin and EMA positive (n=11), the other mostly cytokeratin negative, EMA positive, bcl-2 positive and mostly CD56 positive (n=9). Malignant peripheral nerve sheath tumor clustered into two groups: one S100 positive, with nestin and NGFR positivity in most (n=10), the other mostly S100 negative, and variably but mostly weakly positive for nestin and NGFR (n=11). Ewing sarcomas clustered into a single group driven by membranous CD99 staining. Thirteen cases failed to cluster (outliers), while three Ewing sarcomas clustered into groups of other tumor types. Paired antibodies for each tumor type determined by visual assessment of cluster analysis data and statistical calculations of specificity, sensitivity, and predictive values showed that EMA/CK7 for synovial sarcoma, nestin/S100 for malignant peripheral nerve sheath tumor, and membranous CD99/Fli-1 for Ewing sarcoma yielded high specificity and positive predictive values. Cluster analysis also highlighted aberrant staining reactions and diagnostic pitfalls in these tumors. Hierarchical cluster analysis is an effective method for analyzing high-volume immunohistochemical data.

Diagnostic value of CD163 in cutaneous spindle cell lesions

Background:  The histologic diagnosis of atypical fibroxanthoma (AFX) can sometimes be challenging. No specific marker exists to confirm the diagnosis other than excluding other entities. CD163 has been shown to have great specificity for tumors of monocyte/histiocyte lineage. In this study, we evaluated the diagnostic utility of CD163 in diagnosing AFX and in identifying skin lesions with histiocytic/dendritic derivation.

White sponge nevus presenting as genital lesions in a 28‐year‐old female

A case is presented of white plaques occurring predominantly on the vulvar mucosa of a 28‐year‐old female diagnosed as white sponge nevus (WSN). WSN is a rare, autosomal dominant disorder involving mucous membranes. It predominantly affects the oral mucosa; however, it has been reported to rarely involve extraoral mucosal sites. In this case, histology and family history were key features leading to the correct diagnosis. WSN is an extremely rare cause of vulvar leukoplakia, yet it is important to recognize to allow for appropriate genetic counseling of this autosomal dominant disorder and to avoid misdiagnosis and the potential for subsequent exposure to ineffective treatment modalities.

Telomerase expression in sebaceous lesions of the skin.

Background:  Recent studies have demonstrated telomerase expression in ophthalmologic sebaceous carcinoma and have suggested possible diagnostic utility in distinguishing these neoplasms from sebaceous adenomas. The aim of this study was to evaluate telomerase expression via human telomerase reverse transcriptase (hTERT) immunohistochemical staining in a spectrum of sebaceous lesions of the skin.

Paraneoplastic Pemphigus in a Burn Intensive Care Unit: Case Report and Review of the Literature

Paraneoplastic pemphigus is a rare cause of acute diffuse blistering in the adult patient. It commonly presents with subepidermal blistering, epidermal necrosis, and symptoms of mucosal irritation, such as conjunctivitis and vaginal ulceration. Because of its rarity, it is frequently misdiagnosed as Stevens-Johnson syndrome or toxic epidermal necrolysis. In this study, the authors will describe clinical and histologic manifestations of paraneoplastic pemphigus. This case report describes a 45-year-old woman with paraneoplastic pemphigus who was admitted and treated in a burn intensive care unit. Although initially diagnosed with Stevens-Johnson syndrome, the patient had progression of desquamation when potentially offending medications were discontinued. Diffuse adenopathy was noted on examination, and biopsy confirmed a low-grade lymphoma. Paraneoplastic pemphigus is a rare but important cause of acute diffuse blistering in adults. This disorder should be considered in the differential diagnosis of patients with diffuse blistering.

Clusterin expression in cutaneous CD30‐positive lymphoproliferative disorders and their histologic simulants

Background:  Clusterin is a ubiquitous 80 kDa heterodimeric glycoprotein previously shown to be expressed on tumor cells of systemic and, to a lesser extent, primary cutaneous anaplastic large cell lymphoma (PC‐ALCL). Lymphomatoid papulosis (LyP), an important differential diagnosis of ALCL, has been studied for clusterin expression in only a small number of cases. The aim of this study was to compare clusterin immunostaining patterns in LyP and other cutaneous histologic simulants with those of PC‐ALCL.

Fine-needle aspiration cytology of metastatic eccrine porocarcinoma

Eccrine porocarcinoma (EP), although rare, is widely recognized as the most common malignant sweat gland tumor. EP typically grows slowly and usually is cured by surgical excision with clear margins. An elevated mortality rate, however, is observed when regional lymph nodes are involved. We herein describe cytohistologic findings in a case of metastatic EP. An 86‐year‐old man with a history of EP of the left lateral ankle and squamous cell carcinoma in situ (Bowens disease) of the penis presented with enlarged left inguinal lymph nodes. A superficial fine‐needle aspiration (FNA) was performed and demonstrated a hypercellular sample with discohesive clusters and/or individual tumor cells. The tumor cells were round or oval with most of the cells showing dense, refractile cytoplasm. Intracytoplasmic vacuoles were readily appreciated in some of the cells. Nuclear enlargement, high N/C ratio, nuclear hyperchromasia, bi‐ and multinucleation, and prominent nucleoli were seen. A diagnosis of metastatic eccrine porocarcinoma was rendered. Enlarged retroperitoneal lymph nodes were detected and CT‐guided left retroperitoneal core biopsy was performed 1 week later. The biopsy revealed features consistent with metastatic eccrine porocarcinoma. Diagn. Cytopathol. 2009.

Multinodular lesions of the earlobes.

A 58-year-old man presented with a 7-year history of a lump on the plantar aspect of his left foot. The lesion had slowly enlarged within the preceding 2 years. The patient described intense pain of the left foot during walking or exercise. Dermatological examination revealed a round, rubbery, flesh-colored, 1.5-cm palpable nodule on the volar aspect of the left foot, corresponding with the area of the third metatarsophalangeal joint (Figure 1). The lesion was slightly tender when squeezed between the thumb and index finger. Figure 2 and Figure 3 show a 4-mm punch biopsy specimen obtained from the nodule. What is your diagnosis?