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.

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. METHODS: Formalin-fixed, paraffin-embedded sections of PC-ALCL (6), LyP (20), mycosis fungoides with large cell transformation (MF-LCT, 12), pityriasis lichenoides et varioliformis acuta (PLEVA, 12), arthropod bite reaction (ABR, 12) and lymphomatoid reactions (LR, 9) were immunostained for clusterin and evaluated for staining pattern and distribution. All diagnoses were made with clinicopathologic correlation. RESULTS: Characteristic dot-like Golgi staining was identified in 10/20 LyP (50%), 4/6 PC-ALCL (67%) and 9/12 MF-LCT (75%). Two of 12 PLEVA (17%), 1 of 12 ABR (8%) and 2 of 8 LR (25%) had lymphocytes (< 25%) with diffuse cytoplasmic staining. Dermal dendritic cells stained strongly for clusterin. High background staining occurred in some cases. CONCLUSION: Clusterin immunostaining does not reliably distinguish between LyP, PC-ALCL or MF-LCT, but could distinguish LyP from its reactive histologic simulants.

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. METHODS: A total of 157 cases, including 14 AFXs, 5 spindle cell squamous cell carcinomas (SCCs), and 7 spindle cell/desmoplastic melanomas, along with other cutaneous spindle cell and histiocytic/fibrohistiocytic lesions, were stained with CD163. RESULTS: CD163 was expressed in 11 of 14 (79%) AFXs, with moderate to strong intensity. No staining was observed in cases of spindle cell SCC (0/5) and dermatofibrosarcoma protuberans (0/10). Rare spindle cell/desmoplastic melanomas (2/7) and cutaneous leiomyosarcomas (1/5) demonstrated positive staining. CD163 reactivity was seen in 24 of 29 of benign fibrous histiocytomas (BFHs), including 8 of 8 cellular fibrous histiocytomas and 6 of 9 epithelioid cell histiocytomas. The majority of cutaneous histiocytic lesions, including juvenile xanthogranuloma, Langerhans cell histiocytosis and Rosai-Dorfman disease, were positive for CD163. CONCLUSION: CD163 is a useful adjunct in distinguishing AFX from other malignant cutaneous spindle cell tumors and offers improved specificity in identifying cutaneous histiocytic/dendritic lesions.

Mucosal melanoma of the head and neck: predictors of prognosis.

OBJECTIVES: To identify significant clinical and pathological predictors of survival in mucosal melanoma of the head and neck. DESIGN: Retrospective case series. We reviewed cases of mucosal melanoma of the head and neck from a prospectively collected database after institutional review board approval. SETTING: A single academic institution. PATIENTS: Fifty-two patients with mucosal melanoma of the head and neck. RESULTS: With a median follow-up of 97 months, the median overall survival was 52 months, with a 5-year overall survival of 38%. The median disease-free survival was 15 months, with a 5-year disease-free survival of 22%. Younger age (P = .02), lower T status (P = .003), and lower American Joint Committee on Cancer stage (P < .001) were associated with better overall survival. Positive surgical margins predicted poorer overall survival (P = .01), but patients who required reexcision to achieve negative margins had outcomes that were not significantly different from those with initially negative surgical margins (P = .71). Sex, smoking history, and primary site did not affect disease-free or overall survival. Adjuvant radiotherapy and/or chemotherapy did not predict improved outcomes. Fewer mitoses (P = .02) and the absence of ulceration (P = .01) predicted improved overall survival. CONCLUSIONS: Our experience confirms the utility of current staging systems in predicting outcomes of mucosal melanoma of the head and neck and stresses the importance of achieving negative surgical margins. Pathologically, fewer mitoses and the absence of ulceration predict better outcomes and should be reported as part of routine histological profiles of mucosal melanoma. Further studies are necessary to change the paradigm of care for this rare and deadly disease.

Cutaneous adnexal differentiation and stromal metaplasia in palate pleomorphic adenomas: a potential diagnostic pitfall that may be mistaken for malignancy.

Cutaneous adnexal differentiation is well-recognized in benign mixed tumors occurring in cutaneous sites. The incidence of this histologic finding in salivary gland sites is not known. We sought to describe the incidence of cutaneous adnexal differentiation in benign mixed tumors of the palate, lip, and parotid gland. Benign mixed tumors of the palate (n=30), lip (n=13), and parotid gland (n=37) resected between 1980 and 2009 at a single academic medical institution were reviewed. All hematoxylin and eosin-stained sections containing neoplasm were reviewed by all authors including one dermatopathologist (S.H.O.). After confirming the diagnosis of benign mixed tumor, we evaluated for morphologic evidence of cutaneous adnexal differentiation and metaplastic epithelial and stromal changes. Chart review was conducted to obtain pertinent clinical information. Cutaneous adnexal differentiation was seen in 20% of palate and 39% of lip benign mixed tumors but in no parotid tumors. The most frequent features of cutaneous adnexal differentiation were tricholemmal differentiation (20% of palate and 39% of lip tumors), infundibulocystic structures (17% and 31%), and trichohyalin granules (13% and 31%). Sebaceous differentiation was seen in only one palate tumor. Varying amounts of stromal adipose were seen in 62, 37, and 22% of lip, palate, and parotid tumors. Osseous metaplasia was seen in one tumor from each site. When cutaneous adnexal differentiation occurs in salivary gland pleomorphic adenomas, it can present a diagnostic pitfall that must not be misinterpreted as carcinoma at biopsy, fine needle aspiration, or frozen section.

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.

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. METHODS: Paraffin-embedded sections from sebaceous hyperplasia (11), nevus sebaceus (22), sebaceous adenoma (19), sebaceoma (11), and sebaceous carcinoma (14) were evaluated for intensity (0 to 3+) and pattern of anti-hTERT staining. RESULTS: Strong (2 to 3+) hTERT staining was observed in nucleoli of germinative cells and immature sebocytes in all sebaceous lesions, whereas mature sebocytes were negative. The distribution pattern paralleled features seen by routine haematoxylin and eosin-stained sections. CONCLUSIONS: All hyperplastic and neoplastic sebaceous skin lesions expressed hTERT in this immunohistochemical study. The pattern of staining was predictive of the histologic pattern of the process but does not significantly add to our diagnostic armamentarium of sebaceous lesions.

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.

Neutrophil CD64 is an improved indicator of infection or sepsis in emergency department patients.

CONTEXT: Sepsis, affecting millions of individuals annually with an associated high mortality rate, is among the top 10 causes of death. In addition, improvements in diagnostic tests for detecting and monitoring sepsis and infection have been limited in the last 25 years. Neutrophil CD64 expression has been proposed as an improved diagnostic test for the evaluation of infection and sepsis. OBJECTIVE: To evaluate the diagnostic performance of a quantitative flow cytometric assay for leukocyte CD64 expression in comparison with the standard tests for infection/sepsis in an ambulatory care setting. DESIGN: Prospective analysis of 100 blood samples from patients from an emergency department setting in a 965-bed tertiary care suburban community hospital was performed for neutrophil CD64 expression, C-reactive protein, erythrocyte sedimentation rate, and complete blood count. The laboratory findings were compared with a clinical score for the likelihood of infection/sepsis, which was obtained by a blinded retrospective chart review. RESULTS: The diagnostic performance, as gauged by the clinical score, varied with neutrophil CD64 (sensitivity 87.9%, specificity 71.2%, efficiency 76.8%) and outperformed C-reactive protein (sensitivity 88.2%, specificity 59.4%, efficiency 69.4%), absolute neutrophil count (sensitivity 60.0%, specificity 50.8%, efficiency 53.8%), myeloid left shift (sensitivity 68.2%, specificity 76.3%, efficiency 73.3%), and sedimentation rate (sensitivity 50.0%, specificity 65.5%, efficiency 61.0%). CONCLUSION: Neutrophil CD64 expression quantitation provides improved diagnostic detection of infection/sepsis compared with the standard diagnostic tests used in current medical practice.