Conjunctival stromal tumour (COST): anterior-segment OCT findings.

Conjunctival stromal tumour (COST) is a recently described rare conjunctival tumour of mesenchymal origin with only four publications describing a handful of cases thus far. In this report, we describe the anterior-segment optical coherence tomography (AS-OCT) characteristics in a case of COST for the first time, in addition to the clinical and histopathological characteristics. The AS-OCT showed an elevated, dome-shaped hyporeflective homogenous lesion in the conjunctival stroma lined by hyperreflective outer layer with mild posterior shadowing, consistent with histological description of a paucicellular tumour with large myxoid collagenous material inside. Immunohistochemistry showed positive CD34 and vimentin but negative S100 and smooth muscle actin, thereby differentiating it from conjunctival myxoma.

Utility of Multistep Protocols in the Analysis of Sentinel Lymph Nodes in Cutaneous Melanoma: An Assessment of 194 Cases.

CONTEXT.­: Currently, no universal protocol exists for the assessment of sentinel lymph nodes (SLNs) in cutaneous melanoma. Many institutions use a multistep approach with multiple hematoxylin-eosin (H&E) and immunohistochemical stains. However, this can be a costly and time- and resource-consuming task. OBJECTIVE.­: To assess the utility for multistep protocols in the analysis of melanoma SLNs by specifically evaluating the Calgary Laboratory Services (CLS) protocol (which consists of 3 H&E slides and 1 S100 protein, 1 HMB-45, and 1 Melan-A slide per melanoma SLN block) and to develop a more streamlined protocol. DESIGN.­: Histologic slides from SLN resections from 194 patients with diagnosed cutaneous melanoma were submitted to the CLS dermatopathology group. Tissue blocks were processed according to the CLS SLN protocol. The slides were re-reviewed to determine whether or not metastatic melanoma was identified microscopically at each step of the protocol. Using SPSS software, a decision tree was then created to determine which step most accurately reflected the true diagnosis. RESULTS.­: We found with Melan-A immunostain that 337 of 337 negative SLNs (100%) were correctly diagnosed as negative and 55 of 56 positive nodes (98.2%) were correctly diagnosed as positive. With the addition of an H&E level, 393 of 393 SLNs (100%) were accurately diagnosed. CONCLUSIONS.­: We recommend routine melanoma SLN evaluation protocols be limited to 2 slides: 1 H&E stain and 1 Melan-A stain. This protocol is both time- and cost-efficient and yields high diagnostic accuracy.

Assessment of the cellular localisation of the annexin A2/S100A10 complex in human placenta.

The AnxA2/S100A10 complex has been implicated in various placental functions but although the localisation of these proteins individually has been studied, there is no information about the localisation of their complex in situ at the cellular level. Using the proximity ligation technique, we have investigated the in situ localisation of AnxA2/S100A10 complex in the placenta and have compared this with the location patterns of the individual proteins. High levels of expression of AnxA2/S100A10 complexes were observed in the amniotic membrane and in blood vessel endothelial cells. Lower levels were detected in the brush border area of the syncytium and in the trophoblasts. Immunohistochemical analysis of AnxA2 and S100A10 individually revealed broadly similar patterns of localisation. The brush border staining pattern suggests that in this location at least some of the AnxA2 is not in complex with S100A10. The formal location of the AnxA2/S100A10 complex is compatible with a role in cell-cell interaction, intracellular transport and secretory processes and regulation of cell surface proteases, implying contributions to membrane integrity, nutrient exchange, placentation and vascular remodelling in different parts of the placenta. Future applications will allow specific assessment of the association of the complex with pathophysiological disorders.

Assessment of antigen presenting cell infiltration in lung tissues of patients with bronchiectasis.

BACKGROUND: Bronchiectasis is a chronic disease characterized by permanent dilatation of the conducting airways accompanied by sustained inflammation. AIMS: To assess whether chronic inflammation of lungs in bronchiectasis is associated with alterations in the numbers of infiltrating antigen presenting cell (APC). SETTING AND DESIGN: Lobectomy specimens from 12 nonsmoker, nonasthmatic patients with acquired (noncongenital) bronchiectasis and six control patients were included in the study. Histopathology slides were reviewed, and immunohistochemical markers for dendritic cells (DCs) macrophages and Langerhans cells have been applied and analyzed. MATERIALS AND METHODS: Tissue specimens were stained by immunohistochemistry using markers for DCs (CD83 and CD23), macrophages (CD68 and CD163), and Langerhans cells (CD1A and S-100 protein). The mean cell counts of stained cells in five high power microscopic fields were recorded. STATISTICAL ANALYSIS USED: Descriptive statistics, mean, standard deviation, median, and interquartile range were used. A nonparametric Mann-Whitney U-test was used to compare cell counts between bronchiectasis and control patients. P <0.05 was considered significant. RESULTS: The mean age of patients with bronchiectasis and controls was 36.7 ± 16.6 and 31.8 ± 22.6 years, respectively. The predominant cell type among the patients was macrophage (median 50.5) followed by DCs (median 44.85), histiocytes (median 32), and Langerhans cells (median 5%). Compared to the controls a significantly higher number of macrophages (P = 0.01), DCs (P = 0.001), and Langerhans cells (P = 0.014) were present. CONCLUSION: Chronic inflammatory response in acquired (noncongenital) bronchiectasis is most probably mediated by increased infiltration of APCs in lung tissues.

Flow cytometry assessment of residual melanoma cells in tumor-infiltrating lymphocyte cultures.

Adoptive transfer of tumor-infiltrating lymphocytes (TIL) is in development for the treatment of metastatic melanoma. In phase II clinical trials, patients with metastatic melanoma that received TIL after preconditioning had a 50-70% clinical response rate. The current approach to generate TIL is to culture melanoma enzyme digests in the presence of IL-2 for a 10- to 20-day period followed by 2 weeks of rapid expansion (REP). Prior to administration, cell therapies are characterized and tested for purity. TIL are characterized by CD3 surface marker expression, and purity is assessed by the amount of tumor remaining in culture. Evaluating TIL purity has traditionally been done by immunohistochemistry, which is often considered semiquantitative. To generate a quantitative assay, we used multiparameter flow cytometry to evaluate the presence of viable tumor cells by staining TIL populations with a viability dye and an antibody cocktail that detects intracellular tumor-antigens gp100, Mart-1, tyrosinase, S100, and surface tumor-antigen melanoma chondroitin sulfate proteoglycan (MCSP), and CD3 on T cells. Tumors were identified by gating on the viable CD3(-) population. Antigens in tumors were initially optimized with individual antibodies using both immunohistochemistry and flow cytometry. When eight different tumor cell lines were spiked into an activated T cell culture, flow cytometry was able to distinguish lymphocytes from tumors in all samples tested. Most importantly, the assay was able to detect melanoma cells in all enzyme digests (9/9) from patient samples. After IL-2-induced TIL expansion, there was a significant decrease in tumor cells; tumor cells were detected in only 2 of 12 samples. In eight IL-2-induced TIL samples that were further expanded in REP, no tumor cells were detected. We have demonstrated that flow cytometry is an alternative to immunohistochemistry for defining the purity of a TIL population.

Prognostic value of [18F]-fluoro-deoxy-glucose PET/CT, S100 or MIA for assessment of cancer-associated mortality in patients with high risk melanoma.

PURPOSE: To assess the prognostic value of FDG PET/CT compared to the tumor markers S100B and melanoma inhibitory activity (MIA) in patients with high risk melanoma. METHODS: Retrospective study in 125 consecutive patients with high risk melanoma that underwent FDG PET/CT for re-staging. Diagnostic accuracy and prognostic value was determined for FDG PET/CT as well as for S100B and MIA. As standard of reference, cytological, histological, PET/CT or MRI follow-up findings as well as clinical follow-up were used. RESULTS: Of 125 patients, FDG PET/CT was positive in 62 patients. 37 (29.6%) patients had elevated S100B (>100 pg/ml) and 24 (20.2%) had elevated MIA (>10 pg/ml) values. Overall specificities for FDG PET/CT, S100B and MIA were 96.8% (95% CI, 89.1% to 99.1%), 85.7% (75.0% to 92.3%), and 95.2% (86.9% to 98.4%), corresponding sensitivities were 96.8% (89.0% to 99.1%), 45.2% (33.4% to 55.5%), and 36.1% (25.2% to 48.6%), respectively. The negative predictive values (NPV) for PET/CT, S100B, and MIA were 96.8% (89.1% to 99.1%), 61.4% (50.9% to 70.9%), and 60.6% (50.8% to 69.7%). The positive predictive values (PPV) were 96.7% (89.0% to 99.1%), 75.7% (59.9% to 86.6%), and 88.0% (70.0% to 95.8%). Patients with elevated S100B- or MIA values or PET/CT positive findings showed a significantly (p<0.001 each, univariate Cox regression models) higher risk of melanoma associated death which was increased 4.2-, 6.5- or 17.2-fold, respectively. CONCLUSION: PET/CT has a higher prognostic power in the assessment of cancer-associated mortality in melanoma patients compared with S100 and MIA.

The economic impact of S-100B as a pre-head CT screening test on emergency department management of adult patients with mild traumatic brain injury.

Recent research suggests that serum S-100B may serve as a good pre-head computed tomography (CT) screening test because of its high sensitivity for abnormal head CT scans. The potential economic impact of using S-100B in the emergency department setting for management of adult patients with isolated mild traumatic brain injury (mTBI) has not been evaluated despite its clinical implementation in Europe. Using evidence from the literature, we constructed a decision tree to compare the average cost per patient of using S-100B as a pre-head CT screening test to the current practice of ordering CT scans based on patients' presenting symptoms without the aid of S-100B. When compared to scanning 45-77% of isolated mTBI patients based upon their presenting symptoms, using S-100B as a pre-head CT screen does not lower hospital costs ($281 versus $160), primarily due to its low specificity for abnormal head CT scans. Sensitivity analyses showed, however, that S-100B becomes cost-lowering when the proportion of mTBI patients being scanned exceeds 78%, or when final CT scan results require 96 min or more than the wait for blood test results. Generally speaking, if blood test results require less time than imaging, and if head CT scan rates for patients with isolated mTBI are relatively high, using S-100B will lower costs. Recommendations for using S-100B as a screening tool should account for setting-specific characteristics and their consequent economic impacts. Despite its high sensitivity and excellent negative predictive value, serum S-100B has low specificity and low positive predictive value, limiting its ability to reduce numbers of CT scans and hospital costs.

Clinical usefulness of a biomarker-based diagnostic test for acute stroke: the Biomarker Rapid Assessment in Ischemic Injury (BRAIN) study.

BACKGROUND AND PURPOSE: One of the significant limitations in the evaluation and management of patients with suspected acute cerebral ischemia is the absence of a widely available, rapid, and sensitive diagnostic test. The objective of the current study was to assess whether a test using a panel of biomarkers might provide useful diagnostic information in the early evaluation of stroke by differentiating patients with cerebral ischemia from other causes of acute neurological deficit. METHODS: A total of 1146 patients presenting with neurological symptoms consistent with possible stroke were prospectively enrolled at 17 different sites. Timed blood samples were assayed for matrix metalloproteinase 9, brain natriuretic factor, d-dimer, and protein S100beta. A separate cohort of 343 patients was independently enrolled to validate the multiple biomarker model approach. RESULTS: A diagnostic tool incorporating the values of matrix metalloproteinase 9, brain natriuretic factor, d-dimer, and S-100beta into a composite score was sensitive for acute cerebral ischemia. The multivariate model demonstrated modest discriminative capabilities with an area under the receiver operating characteristic curve of 0.76 for hemorrhagic stroke and 0.69 for all stroke (likelihood test P<0.001). When the threshold for the logistic model was set at the first quartile, this resulted in a sensitivity of 86% for detecting all stroke and a sensitivity of 94% for detecting hemorrhagic stroke. Moreover, results were reproducible in a separate cohort tested on a point-of-care platform. CONCLUSIONS: These results suggest that a biomarker panel may add valuable and time-sensitive diagnostic information in the early evaluation of stroke. Such an approach is feasible on a point-of-care platform. The rapid identification of patients with suspected stroke would expand the availability of time-limited treatment strategies. Although the diagnostic accuracy of the current panel is clearly imperfect, this study demonstrates the feasibility of incorporating a biomarker based point-of-care algorithm with readily available clinical data to aid in the early evaluation and management of patients at high risk for cerebral ischemia.

The Spitzoid lesion: rethinking Spitz tumors, atypical variants, 'Spitzoid melanoma' and risk assessment.

Although much remains to be learned about Spitzoid lesions, there is increasing evidence that these tumors may be a type of melanocytic neoplasm distinct from conventional melanocytic nevi and malignant melanoma. In the current communication, the author has attempted to describe accurately the state-of-the-art surrounding these lesions, their nomenclature, and assessment of risk. Acknowledging the peculiar nature of Spitzoid lesions, the author prefers the term Spitz tumor rather than 'Spitz nevus' (except perhaps for the most typical lesions) and argues against using the term 'Spitzoid melanoma' until more information is available to justify such a term. The author also believes that patients are best served by the comprehensive evaluation of Spitzoid lesions and their classification into three categories: (1) Spitz tumor without significant abnormality, (2) Spitz tumor with one or more atypical features (atypical Spitz tumor), including those judged to have indeterminate biological potential, and (3) malignant melanoma, rather than the two categories of 'Spitz nevus' and melanoma. Only rigorous characterization of sufficient numbers of Spitzoid lesions and long-term follow-up of patients will provide truly objective information for the formulation of optimal guidelines for the management of patients with these lesions.

Ultrasound examination of sentinel nodes in the initial assessment of patients with primary cutaneous melanoma.

BACKGROUND: The value of targeted high-resolution ultrasound (US) examination in detecting sentinel lymph node metastases in patients with newly diagnosed primary cutaneous melanomas has not yet been fully evaluated. The aim of this study was to determine the threshold size of metastatic melanoma deposits in SLNs able to be detected by targeted US examination before initial melanoma surgery. METHODS: A total of 304 patients presenting with primary cutaneous melanomas had SLNs identified by lymphoscintigraphy and then examined in situ by the same physician with high-resolution US. Within 24 hours, the SLNs were removed for histopathologic assessment of sections stained conventionally and with immunohistochemical markers for S100 protein and HMB45 antigen. RESULTS: Metastatic disease was present in SLNs from 33 node fields in 31 patients. The US results in seven of these cases were suggestive of metastatic disease. Twenty-six node fields contained positive nodes not detected by US. Undetected deposits had diameters <4.5 mm. CONCLUSIONS: These results suggest that a targeted US examination of SLNs can detect metastatic melanoma deposits down to approximately 4.5 mm in diameter. However, most metastatic melanoma deposits in SLNs are considerably smaller than this at the time of initial staging, and US therefore cannot be considered cost-effective in this setting.

Granular cell tumor: immunohistochemical assessment of inhibin-alpha, protein gene product 9.5, S100 protein, CD68, and Ki-67 proliferative index with clinical correlation.

CONTEXT: Granular cell tumor (GCT) is a rare tumor of nerve sheath origin with a predilection for upper aerodigestive tract, skin, and soft tissue. The neoplastic cells typically express S100 and CD68 (KP-1), the latter due to cytoplasmic lysosome content. However, the histogenesis of this tumor is unknown. Additionally, distinction between benign and malignant GCT is difficult because of histologic similarity and lack of reliable criteria that can predict clinical behavior. OBJECTIVE: To perform a comparative, side-by-side immunohistochemical assessment of the traditional immunohistochemical markers for GCTs (S100, CD68), along with the newer markers (inhibin-alpha, protein gene product 9.5) for these tumors. DESIGN: To address diagnostic and prognostic issues, we studied 30 specimens of GCT (27 primary and 3 recurrent tumors, 2 of which occurred consecutively in the same patient) for (1) nuclear pleomorphism, prominent nucleoli, necrosis, spindling, high nuclear-cytoplasmic ratio, and mitoses; (2) immunohistochemical expression of inhibin-alpha, protein gene product 9.5, S100, CD68 (KP-1), and Ki-67 using the avidin-biotin complex method on formalin-fixed, paraffin-embedded sections; and (3) correlation between tumor grade, proliferative fraction, and clinical data. RESULTS: Twenty-seven of 27 primary GCTs and 1 of 3 recurrent GCTs had typical histologic features, while the 2 consecutive recurrent GCT specimens from the same patient were atypical (moderate nuclear atypia and prominent nucleoli alone). The mean age for primary GCT was 37.3 years (range, 5-67 years), and mean size was 1.89 cm. None of the cases metastasized. All 30 specimens showed diffuse (2+ to 3+) staining for S100, CD68, and inhibin-alpha, and 3+ staining for protein gene product 9.5; pseudoepitheliomatous hyperplasia was nonreactive. The Ki-67 proliferative index was less than 1% to 20% in typical nonrecurrent cases, 1% in the typical recurrent case, and 1% and 10% in 2 sequential recurrences of the atypical case. CONCLUSION: Our study expands the immunophenotype of GCT (S100, CD68, protein gene product 9.5, and inhibin-alpha) regardless of location and supports a neural origin. Intensity of immunohistochemical staining had no prognostic significance. Although 1 of the 2 recurrent GCTs had atypical features, the Ki-67 proliferative index did not distinguish reliably between typical (nonrecurrent) and atypical or recurrent GCTs. The significance of inhibin expression with regard to cell differentiation and pathogenesis is unclear and warrants further investigation.

The usefulness of tyrosinase in the immunohistochemical assessment of melanocytic lesions: a comparison of the novel T311 antibody (anti-tyrosinase) with S-100, HMB45, and A103 (anti-melan-A).

AIM: To compare the sensitivity and staining pattern of the new immunohistochemical antibody to tyrosinase (T311) with S-100, HMB45, and the recently evaluated antibody to melan-A (A103) in a range of melanocytic lesions. METHOD: Archival, formalin fixed, paraffin wax embedded sections from 50 benign and malignant melanocytic lesions were stained immunohistochemically with anti-tyrosinase, A103, S-100, and HMB45. They were scored semiquantitatively for the distribution and intensity of staining. RESULTS: All melanomas, with the exception of desmoplastic melanoma, showed some staining with all four antibodies. Overall, T311 and A103 showed an intermediate sensitivity compared with that of S-100 and HMB45. T311 stained most benign and malignant lesions strongly and diffusely with minimal background staining. Immunoreactivity was found to be patchy in some naevi, with weak or absent staining of the mature melanocytes. A103 showed strong and diffuse staining of all benign lesions and most melanomas with minimal background staining. S-100 was the most sensitive, with diffuse staining of most lesions, including desmoplastic and metastatic melanoma, but lacked specificity. HMB45 was the least sensitive antibody, frequently demonstrating patchy staining with absent staining in some benign naevi. CONCLUSIONS: S-100 remains the most sensitive marker of melanocytes. However, because of its lack of specificity, it should be used with at least one other more specific antibody. HMB45 is more specific, but lacks sensitivity; T311 is a reliable marker of melanocytes in paraffin wax embedded sections and is worth consideration for use in a staining panel, although it shows no additional benefit over A103.

Langerhans cell histiocytosis of lymph nodes: a morphological assessment of 43 biopsies.

The morphology of Langerhans cell histiocytosis (LCH) involving lymph nodes was analyzed in 43 biopsies from 39 patients and findings were correlated with clinical data. Five histological motifs were recognized: sinusoidal, limited sinusoidal, epithelioid granulomatous, partial effacement, and total effacement. Lesions were composed of histiocytes of the Langerhans cell (LC) family, macrophages, multinucleated giant histiocytes, T lymphocytes, and eosinophils in varying proportions. Proliferative fractions ranged from 2.6 to 48% and 2 of 25 specimens showed a hyperdiploid aneuploid DNA ploidy profile. Epithelioid granulomas composed of histiocytes with the LC phenotype dominated three abdominal specimens, reflecting a picture of LCH not previously reported. Total effacement seen in three patients, was associated with unmarked histiocytoid cells, high proliferative fraction, aneuploid DNA ploidy profile, and, in two, a fatal outcome. Different histologic appearances in lesions from separate sites of the same patient were seen in the cases with epithelioid granulomas and in those with total effacement. The diverse histopathology in lymph nodes involved by LCH is considered in the context of current knowledge of this enigmatic disease.

Histochemical assessment of the intrinsic innervation of the normal urinary bladder.

In order to assess the normal intrinsic innervation pattern, an enzyme histochemical acetylcholinesterase and two immunohistochemical (S100 protein and neurofilaments) stainings were done on 38 normal urinary bladder specimens. The nerve density was calculated as a mean number of nerve fibers counted per high power field. S100 staining after adequate fixation proved to be similar to the acetylcholinesterase technique, avoids freezing manipulation, is easier to read and permits normal conventional histological examination. Neuropathology of bladder biopsies is an easily available diagnostic method in current neurourological practice.

S-100 protein immunohistochemistry and electron microscopy in the diagnosis of Langerhans cell proliferative disorders: a comparative assessment.

To better define the roles of S-100 protein immunohistochemistry and electron microscopy in the diagnosis of Langerhans cell proliferative disorders, a comparative assessment of the two techniques was performed using material from 39 cases of histiocytosis X and 2 cases of infantile self-healing reticulohistiocytoma. Both techniques proved highly reliable, but neither alone enabled diagnostic confirmation in all instances. The two techniques proved complementary and used together did enable identification of Langerhans-type histiocytes in all cases studied. Neither was judged clearly superior and both offered certain advantages. Electron microscopy was found overall to be a slightly less sensitive technique, but more specific and less subject to misinterpretation. The S-100 stain was found to be particularly useful in situations where sampling problems were likely to be encountered or where the available specimen was otherwise suboptimal for electron microscopic examination. Because the S-100 stain is the more cost-effective to employ, we now recommend it for the purpose of providing routine diagnostic confirmation. In an investigative setting, however, we continue to recommend electron microscopy as the primary technique.