Suppressed-scattering spectral windows for radiative cooling applications.

The scattering of light by resonant nanoparticles is a key process for enhancing the solar reflectance in daylight radiative cooling. Here, we investigate the impact of material dispersion on the scattering performance of popular nanoparticles for radiative cooling applications. We show that, due to material dispersion, nanoparticles with a qualitatively similar response at visible frequencies exhibit fundamentally different scattering properties at infrared frequencies. It is found that dispersive nanoparticles exhibit suppressed-scattering windows, allowing for selective thermal emission within a highly reflective sample. The existence of suppressed-scattering windows solely depends on material dispersion, and they appear pinned to the same wavelength even in random composite materials and periodic metasurfaces. Finally, we investigate calcium-silicate-hydrate (CSH), the main phase of concrete, as an example of a dispersive host, illustrating that the co-design of nanoparticles and host allows for tuning of the suppressed-scattering windows. Our results indicate that controlled nanoporosities would enable concrete with daylight passive radiative cooling capabilities.

Silicon carbide as a material-based high-impedance surface for enhanced absorption within ultra-thin metallic films.

The absorption of infrared radiation within ultra-thin metallic films is technologically relevant for different thermal engineering applications and optoelectronic devices, as well as for fundamental research on sub-nanometer and atomically-thin materials. However, the maximal attainable absorption within an ultra-thin metallic film is intrinsically limited by both its geometry and material properties. Here, we demonstrate that material-based high-impedance surfaces enhance the absorptivity of the films, potentially leading to perfect absorption for optimal resistive layers, and a fourfold enhancement for films at deep nanometer scales. Moreover, material-based high-impedance surfaces do not suffer from spatial dispersion and the geometrical restrictions of their metamaterial counterparts. We provide a proof-of-concept experimental demonstration by using titanium nanofilms on top of a silicon carbide substrate.

A lesion model of envy and Schadenfreude: legal, deservingness and moral dimensions as revealed by neurodegeneration.

The study of moral emotions (i.e. Schadenfreude and envy) is critical to understand the ecological complexity of everyday interactions between cognitive, affective, and social cognition processes. Most previous studies in this area have used correlational imaging techniques and framed Schadenfreude and envy as unified and monolithic emotional domains. Here, we profit from a relevant neurodegeneration model to disentangle the brain regions engaged in three dimensions of Schadenfreude and envy: deservingness, morality, and legality. We tested a group of patients with behavioural variant frontotemporal dementia (bvFTD), patients with Alzheimer's disease, as a contrastive neurodegeneration model, and healthy controls on a novel task highlighting each of these dimensions in scenarios eliciting Schadenfreude and envy. Compared with the Alzheimer's disease and control groups, patients with bvFTD obtained significantly higher scores on all dimensions for both emotions. Correlational analyses revealed an association between envy and Schadenfreude scores and greater deficits in social cognition, inhibitory control, and behaviour disturbances in bvFTD patients. Brain anatomy findings (restricted to bvFTD and controls) confirmed the partially dissociable nature of the moral emotions' experiences and highlighted the importance of socio-moral brain areas in processing those emotions. In all subjects, an association emerged between Schadenfreude and the ventral striatum, and between envy and the anterior cingulate cortex. In addition, the results supported an association between scores for moral and legal transgression and the morphology of areas implicated in emotional appraisal, including the amygdala and the parahippocampus. By contrast, bvFTD patients exhibited a negative association between increased Schadenfreude and envy across dimensions and critical regions supporting social-value rewards and social-moral processes (dorsolateral prefrontal cortex, angular gyrus and precuneus). Together, this study provides lesion-based evidence for the multidimensional nature of the emotional experiences of envy and Schadenfreude. Our results offer new insights into the mechanisms subsuming complex emotions and moral cognition in neurodegeneration. Moreover, this study presents the exacerbation of envy and Schadenfreude as a new potential hallmark of bvFTD that could impact in diagnosis and progression.

Assessment of a Combined Panel of Six Serum Tumor Markers for Lung Cancer.

RATIONALE: We have previously identified six serum tumor markers (TMs) (carcinoembryonic antigen, carbohydrate antigen 15.3, squamous cell carcinoma-associated antigen, cytokeratin-19 fragment, neuron-specific enolase, and pro-gastrin-releasing peptide) related to the presence of lung cancer (LC). OBJECTIVES: To validate their individual performance in an independent cohort, and to explore if their combined assessment (≥1 abnormal TM value) is a more accurate marker for LC presence. METHODS: We determined these six TMs in 3,144 consecutive individuals referred to our institution by their primary care physician because of the clinical suspicion of LC. MEASUREMENTS AND MAIN RESULTS: LC was excluded in 1,316 individuals and confirmed in 1,828 patients (1,563 with non-small cell LC and 265 with small cell LC). This study validated the previously reported performance of each individual TM. We also showed that their combined assessment (≥1 abnormal TM) had a better sensitivity, specificity, negative predictive value, and positive predictive value (88.5, 82, 83.7, and 87.3%, respectively) than each TM considered individually and that it increased the diagnostic performance (area under the curve) of a clinical model that included tumor size, age, and smoking status. In patients with radiographic nodules less than 3 cm, the negative predictive value of the TM panel was 71.8%, hence providing some support for a more conservative diagnostic approach. Finally we identified two TMs (neuron-specific enolase and pro-gastrin-releasing peptide) that differentiate the risk of non-small cell LC from that of small cell LC. CONCLUSIONS: The combined assessment of a panel of six serum TMs is a more accurate marker for LC presence than these same TMs considered individually. The potential of these TMs in the diagnostic and screening settings deserves further research.

Risk stratification for advanced colorectal neoplasia according to fecal hemoglobin concentration in a colorectal cancer screening program.

BACKGROUND & AIMS: The latest generation of fecal immunochemical tests (FIT) allows for quantitation of hemoglobin in feces, allowing for selection of optimal cut-off concentrations. We investigated whether individuals with positive results from quantitative FITs, in combination with other factors, could be identified as being at greatest risk for advanced colorectal neoplasia. METHODS: In a retrospective study, we analyzed data from a consecutive series of 3109 participants with positive results from FITs (≥20 µg/g of feces) included in the first round of the Barcelona colorectal cancer screening program, from December 2009 through February 2012. All participants underwent colonoscopy and were assigned to groups with any advanced colorectal neoplasia or with nonadvanced colorectal neoplasia (but with another diagnosis or normal examination findings). RESULTS: Median fecal hemoglobin concentrations were significantly higher in participants with advanced colorectal neoplasia (105 µg/g; interquartile range, 38-288 µg/g) compared with participants with nonadvanced colorectal neoplasia (47 µg/g; interquartile range, 23-119 µg/g) (P < .001). Positive predictive values for advanced colorectal neoplasia, determined using arbitrary fecal hemoglobin concentrations, differed with sex and age. Multivariate logistic regression analysis identified sex (men: odds ratio [OR], 2.07; 95% confidence interval, 1.78-2.41), age (60-69 y: OR, 1.24; 95% confidence interval, 1.07-1.44), and fecal hemoglobin concentration (>177 µg/g: OR, 3.80; 95% confidence interval, 3.07-4.71) as independent predictive factors for advanced colorectal neoplasia. Combining these factors, we identified 16 risk categories associated with different probabilities of identifying advanced colorectal neoplasia. Risk for advanced colorectal neoplasia increased 11.46-fold among individuals in the highest category compared with the lowest category; positive predictive values ranged from 21.3% to 75.6%. CONCLUSIONS: Fecal hemoglobin concentration, in addition to sex and age, in individuals with positive results from FITs can be used to stratify probability for the detection of advanced colorectal neoplasia. These factors should be used to prioritize individuals for colonoscopy examination.

Spectrally stable thermal emitters enabled by material-based high-impedance surfaces.

Radiative thermal engineering with subwavelength metallic bodies is a key element for heat and energy management applications, communication and sensing. Here, we numerically and experimentally demonstrate metallic thermal emitters with narrowband but extremely stable emission spectra, whose resonant frequency does not shift with changes on the nanofilm thickness, the angle of observation and/or polarization. Our devices are based on epsilon-near-zero (ENZ) substrates acting as material-based high-impedance substrates. They do not require from complex nanofabrication processes, thus being compatible with large-area and low-cost applications.

Addressing the Impact of Surface Roughness on Epsilon-Near-Zero Silicon Carbide Substrates.

Epsilon-near-zero (ENZ) media have been very actively investigated due to their unconventional wave phenomena and strengthened nonlinear response. However, the technological impact of ENZ media will be determined by the quality of realistic ENZ materials, including material loss and surface roughness. Here, we provide a comprehensive experimental study of the impact of surface roughness on ENZ substrates. Using silicon carbide (SiC) substrates with artificially induced roughness, we analyze samples whose roughness ranges from a few to hundreds of nanometer size scales. It is concluded that ENZ substrates with roughness in the few nanometer scale are negatively affected by coupling to longitudinal phonons and strong ENZ fields normal to the surface. On the other hand, when the roughness is in the hundreds of nanometers scale, the ENZ band is found to be more robust than dielectric and surface phonon polariton (SPhP) bands.

Utility of serum tumor markers as an aid in the differential diagnosis of patients with clinical suspicion of cancer and in patients with cancer of unknown primary site.

Cancer may be diagnosed in advanced stages, when the patient has already developed metastasis, with symptoms that can be also observed in benign diseases. The objective of this study was to evaluate tumor marker sensitivity and specificity in the differential diagnosis of patients with suspected signs of cancer. We studied 2.711 consecutive patients admitted to the Internal Medicine Department of our hospital with suspected cancer; 1.240 patients had non-malignant processes and 1.471 had malignant disease. Determinations were considered positive for suspected malignancy when serum levels were carcinoembryonic antigen >15 ng/ml (>20 in patients with renal failure or liver disease), alpha fetoprotein >40 ng/ml (>80 ng/ml in patients with liver diseases), carbohydrate antigen (CA) 19.9 > 200 U/ml (>500 U/ml in patients with liver diseases or gamma glutamyl transpeptidase (GGT) <150 UI/L or effusions; >1.000 U/ml in patients with jaundice or GGT > 150 UI/L), neuron-specific enolase >45 ng/ml (renal failure >50 ng/ml; samples with hemolysis were excluded), prostate-specific antigen > 30 ng/ml (excluding acute prostatitis), tumor-associated glycoprotein-72 >80 U/ml, cytokeratin 19 fragment 21-1 > 7.5 ng/ml (>19 ng/ml in patients with renal failure; >11 ng/ml in patients with liver cirrhosis or jaundice), >3.5 ng/ml for squamous cell carcinoma (excluding patients with renal failure or skin disorders), CA 15.3 >100 U/ml, and CA 125 >350 U/ml (>600 U/ml in patients with pleural effusion and >900 U/ml in those with ascites). There was a specificity of 97.6% in patients without malignancy, 67.4% of sensitivity in patients with malignancy, and 75.4% of sensitivity in the 1,280 patients with epithelial tumors (53.7% in patients with locally advanced tumors and 79.4% in patients with metastases). Sensitivity was 81.4% in patients with cancer of unknown primary site. Tumor markers were useful in the differential diagnosis between epithelial and non-epithelial tumors, brain masses (metastases vs. primary tumors), and between benign or malignant origin of different clinical situations such as wasting syndrome, effusions, liver or bone lesions, and effusions with a positive predictive value higher than 95%. Tumor markers are useful as an aid in the evaluation of the risk of cancer of these patients with suspected cancer and may be useful to reduce the hospitalization time, morbidity, and the number of diagnostic tests required for diagnosis.

CA 19-9 in pancreatic cancer: retrospective evaluation of patients with suspicion of pancreatic cancer.

CA 19.9 serum levels were prospectively determined in 573 patients admitted to hospital for suspicion of pancreatic cancer. The final diagnosis was 77 patients with no malignancy, 389 patients with pancreatic cancer, 37 neuroendocrine pancreatic cancer, 28 cholangiocarcinomas, 4 gallbladder cancer, 27 ampullary carcinomas, and 11 periampullary carcinomas. CA 19.9 was determined using a commercial assay from Roche Diagnostics, and 37 U/ml was considered as the upper limit of normality. Abnormal CA 19.9 serum levels were found in 27%, 81.5%, 85.7%, 59.3%, 63.6%, and 18.9% of patients with benign diseases, pancreatic cancer, cholangiocarcinomas, and ampullary, periampullary, or neuroendocrine tumors. Significantly higher concentrations of CA 19.9 were found in patients with than in those without malignancy or with neuroendocrine tumors. CA 19.9 serum levels were higher in pancreatic cancer or cholangiocarcinoma than in other malignancies (p < 0.0001). CA 19.9 serum levels were also correlated with tumor stage, treatment (significantly lower concentrations in resectable tumors), and tumor location (the highest in those located in the body, the lowest in those in the tail or uncinate) and site of metastases (highest in liver metastases). A trend to higher CA 19.9 serum concentrations was found in patients with jaundice, but only with statistical significance in the early stages. Using 50 or 100 U/ml in patients with jaundice, CA 19.9 was useful as an aid in the diagnosis of pancreatic cancer (sensitivity 77.9%, specificity 95.9%) as well as tumor resectability in pancreatic cancer with different cutoffs according to tumor location and bilirubin serum levels with specificities ranging from 90% to 100%. CA 19.9 is the tumor marker of choice in pancreatic adenocarcinomas, with a clear relationship with tumor location, stage, and resectability.

Circulating levels of HER-2/neu oncoprotein in breast cancer.

HER-2/neu, also known as c-erbB-2/neu, is an oncogene located in chromosome 17 which encodes HER-2/neu, a transmembrane protein belonging to the EGFR family. The external domain of this protein is released by the cell and can be studied in serum by immunoassay. HER-2/neu in serum is a specific tumor marker and only slight elevations may be found in the absence of malignancy, mainly in association with liver diseases. Likewise, the highest concentrations of this oncoprotein are found in patients with breast cancer, but lower concentrations may be found in other malignancies, particularly ovarian, prostate and lung cancer (mainly adenocarcinomas). HER-2/neu assay sensitivity in patients with untreated primary loco-regional breast cancer is <10% and seems to be related to overexpression in tissue as well as to the most important prognostic factors: tumor size and nodal involvement. Serial HER-2/neu determinations after surgery seem to be useful in the early diagnosis of recurrence, mainly in patients with HER-2/neu overexpression in tissue, but additional studies are necessary to confirm these results. HER-2/neu sensitivity (proportion of patients with abnormal values) in patients with metastasis is around 40%-45%, with a clear relationship to tissue overexpression and to site (higher in visceral metastases) and number of metastases. The clinical utility of HER-2/neu in patients with advanced disease is mainly for therapeutic monitoring. Likewise, in most of the studies published, a relationship has been found between serum HER-2/neu levels (either pretreatment or at follow-up) with tumor response.

Comparison of serum human epididymis protein 4 with cancer antigen 125 as a tumor marker in patients with malignant and nonmalignant diseases.

BACKGROUND: Human epididymis protein 4 (HE4), a precursor of human epididymis protein, has been proposed as a tumor marker for ovarian cancer. We evaluated HE4 in comparison with cancer antigen 125 (CA 125) in healthy individuals and in patients with benign and malignant diseases. METHODS: CA 125 and HE4 serum concentrations were determined in 101 healthy individuals, 535 patients with benign pathologies (292 with benign gynecologic diseases) and 423 patients with malignant diseases (127 with ovarian cancers). CA 125 and HE4 cutoffs were 35 kU/L and 140 pmol/L, respectively. RESULTS: HE4 and CA 125 results were abnormal in 1.1% and 9.9% of healthy individuals and in 12.3% and 37% of patients with benign diseases, respectively. Renal failure was the most common cause of increased HE4 in patients with benign disease, who had significantly higher HE4 concentrations (P = 0.001) than patients with other benign diseases. HE4 showed a higher specificity than CA 125 in patients with benign gynecologic diseases, with abnormal concentrations in 1.3% and 33.2% of the patients, respectively. HE-4 concentrations were abnormal primarily in gynecologic cancer and lung cancer. By contrast, CA 125 was increased in many different nonovarian malignancies, including nonepithelial tumors. A significantly higher area under the ROC curve was obtained with HE4 than with CA 125 for differentiating benign from malignant diseases (0.755 vs 0.643) and in the differential diagnosis of gynecologic diseases (0.874 vs 0.722). CONCLUSIONS: HE4 has significantly higher diagnostic specificity than CA 125, and the combination of CA 125 and HE4 improved the detection of ovarian cancer in all stages and histological types.

HE4 a novel tumour marker for ovarian cancer: comparison with CA 125 and ROMA algorithm in patients with gynaecological diseases.

The aim of this study is to evaluate a new tumour marker, HE4, in comparison with CA 125 and the Risk of Ovarian Malignancy Algorithm (ROMA) in healthy women and in patients with benign and malignant gynaecological diseases. CA 125 and HE4 serum levels were determined in 66 healthy women, 285 patients with benign gynaecological diseases (68 endometriosis, 56 myomas, 137 ovarian cysts and 24 with other diseases), 33 patients with non-active gynaecological cancer and 143 with active gynaecological cancer (111 ovarian cancers). CA 125 and HE4 cut-offs were 35 U/mL and 150 pmol/L, respectively. ROMA algorithm cut-off was 13.1 and 27.7 for premenopausal or postmenopausal women, respectively. HE4, CA 125 and ROMA results were abnormal in 1.5%, 13.6% and 25.8% of healthy women and in 1.1%, 30.2% and 12.3% of patients with benign diseases, respectively. Among patients with cancer, HE4 (in contrast to CA 125) had significantly higher concentrations in ovarian cancer than in other malignancies (p < 0.001). Tumour marker sensitivity in ovarian cancer was 79.3% for HE4, 82.9% for CA 125 and 90.1% for ROMA. Both tumour markers, HE4 and CA 125 were related to tumour stage and histological type, with the lowest concentrations in mucinous tumours. A significantly higher area under the ROC curve was obtained with ROMA and HE4 than with CA 125 in the differential diagnosis of benign gynaecological diseases versus malignant ovarian cancer (0.952, 0.936 and 0.853, respectively). Data from our population indicate that ROMA algorithm might be further improved if it is used only in patients with normal HE4 and abnormal CA 125 serum levels (cancer risk for this profile is 44.4%). ROMA algorithm in HE4 positive had a similar sensitivity and only increases the specificity by 3.2% compared to HE4 alone.

Lung Ultrasound as a First-Line Test in the Evaluation of Post-COVID-19 Pulmonary Sequelae.

Background: Interstitial lung sequelae are increasingly being reported in survivors of COVID-19 pneumonia. An early detection of these lesions may help prevent the development of irreversible lung fibrosis. Lung ultrasound (LUS) has shown high diagnostic accuracy in interstitial lung disease (ILD) and could likely be used as a first-line test for post-COVID-19 lung sequelae. Methods: Single-center observational prospective study. Follow-up assessments of consecutive patients hospitalized for COVID-19 pneumonia were conducted 2-5 months after the hospitalization. All patients underwent pulmonary function tests (PFTs), high-resolution computed tomography (HRCT), and LUS. Radiological alterations in HRCT were quantified using the Warrick score. The LUS score was obtained by evaluating the presence of pathological B-lines in 12 thoracic areas (range, 0-12). The correlation between the LUS and Warrick scores was analyzed. Results: Three hundred and fifty-two patients who recovered from COVID-19 pneumonia were recruited between July and September 2020. At follow-up, dyspnea was the most frequent symptom (69.3%). FVC and DLCO alterations were present in 79 (22.4%) and 234 (66.5%) patients, respectively. HRCT showed relevant interstitial lung sequelae (RILS) in 154 (43.8%) patients (Warrick score ≥ 7). The LUS score was strongly correlated with the HRCT Warrick score (r = 0.77) and showed a moderate inverse correlation with DLCO (r = -0.55). The ROC curve analysis revealed that a LUS score ≥ 3 indicated an excellent ability to discriminate patients with RILS (sensitivity, 94.2%; specificity, 81.8%; negative predictive value, 94.7%). Conclusions: LUS could be implemented as a first-line procedure in the evaluation of Post-COVID-19 interstitial lung sequelae. A normal LUS examination rules out the presence of these sequelae in COVID-19 survivors, avoiding the need for additional diagnostic tests such as HRCT.

Prospective evaluation of carcinoembryonic antigen (CEA) and carbohydrate antigen 15.3 (CA 15.3) in patients with primary locoregional breast cancer.

BACKGROUND: The utility of carcinoembryonic antigen (CEA) and carbohydrate antigen 15.3 (CA 15.3) as prognostic factors in primary breast cancer is unclear. METHODS: We prospectively studied CEA and CA 15.3 in the sera of 2062 patients with untreated primary breast cancer diagnosed between 1984 and 2008. RESULTS: Increased CEA (>5 microg/L) and CA 15.3 (>30 kU/L) concentrations were found in 12.7% and 19.6% of the patients, respectively, and 1 or both tumor markers were increased in 28% (570 of 2062). Increases in each tumor marker correlated with larger tumor sizes and nodal involvement. Tumor size, estrogen receptor (ER), and CEA were independent prognostic factors by multivariate analysis in the total group [disease free survival (DFS) and overall survival (OS)] as well as in node-positive (NP) and node-negative (NN) patients. Nodal involvement and histological grade were independent prognostic factors in the total group as well as in NP patients. By contrast, adjuvant treatment and CA 15.3 were independent prognostic factors only in NN patients (DFS and OS). All patients with CEA >7.5 microg/L had recurrence during follow-up. Use of both tumor markers allowed discrimination of the groups of risk in T1 NN patients: 56.3% of recurrences were seen when 1 or both tumor markers were increased, whereas only 9.4% of recurrences were seen in T1 NN patients without increases of either marker. CONCLUSIONS: CEA and CA 15.3 are useful prognostic factors in NP and NN breast cancer patients. CEA >7.5 microg/L is associated with a high probability of subclinical metastases.

Evaluation of tumor markers (HER-2/neu oncoprotein, CEA, and CA 15.3) in patients with locoregional breast cancer: prognostic value.

Tumor markers were studied in the sera of 883 untreated patients with primary breast cancer diagnosed between 1989 and 2007. Abnormal human epidermal growth factor receptor 2 (HER-2)/neu levels (>15 ng/mL) were found in 9.5%, carcinoembryonic antigen (CEA) in 15.9%, and cancer antigen (CA) 15.3 in 19.7% of the patients. One or more tumor markers were abnormal in 305 (34.5%) of the 883 studied patients. Significantly higher serum HER-2/neu levels were found in patients with tissue overexpression of this oncoprotein (p < 0.0001). CEA, CA 15.3, and HER-2/neu (only in those patients with tissue overexpression) serum levels were related with tumor stage (tumor size and nodal involvement) and steroid receptors (higher values in estrogen receptor-negative (ER-) tumors). Univariate analysis showed that HER-2/neu serum levels were prognostic factors in disease-free survival (DFS) and overall survival (OS) only in patients with tissue overexpression. Multivariate analysis in 834 patients show that nodal involvement, tumor size, ER, CEA, and adjuvant treatment were independent prognostic factors in DFS and OS. When only patients with HER-2/neu overexpression in tissue were studied, tumor size, nodal involvement, and tumor markers (one or another positive) were independent prognostic factors for both DFS and OS. HER-2/neu serum levels were also an independent prognostic factor, with CEA, ER, and nodes in 106 patients treated with neoadjuvant treatment. In summary, serum HER-2/neu, CEA, and CA 15.3 are useful tools in the prognostic evaluation of patients with primary breast cancer.

Usefulness of serum tumor markers, including progastrin-releasing peptide, in patients with lung cancer: correlation with histology.

BACKGROUND: Tumor markers have been extensively studied in lung cancer, reporting some relationship to the histology, but their clinical utility is not clear. METHODS: ProGRP, CEA, SCC, CA 125, CYFRA 21-1 and NSE were studied prospectively in 155 patients with unconfirmed suspicion of lung cancer and in 647 patients with lung cancer: 182 squamous, 205 adenocarcinomas, 19 large-cell lung cancer (LCLC), 175 small-cell lung cancer (SCLC) and 66 unspecific non-small-cell lung cancer (NSCLC). RESULTS: Abnormal tumor marker serum levels were found in less than 5.3% of the patients with benign diseases, excluding CA 125 (21.3%). Tumor markers were related to histological type and tumor extension with significantly higher CEA (p <0.01) and CA 125 (p <0.007) serum levels in adenocarcinomas, SCC (p <0.0001) and CYFRA 21-1 (p <0.008) in squamous tumors and ProGRP (p <0.0001) and NSE (p <0.0001) in SCLC. Tumor markers may be useful in the histological differentiation of NSCLC and SCLC. Patients with SCC serum levels >2 ng/ml were always NSCLC, while those with SCC <2 ng/ml and ProGRP >100 pg/ml and NSE >35 ng/ml were all SCLC patients. The sensitivity was 76.7 and 79.5%, specificity was 97.2 and 99.6%, with a positive predictive value of 98.6 and 98.6% and a negative predictive value of 60.7 and 92.9% in the differentiation of NSCLC and SCLC, respectively. CONCLUSIONS: Tumor marker determination in patients with suspicious signs of lung cancer suggests, in a few hours, the histological diagnosis in the majority of lung cancer patients.

Multicenter evaluation of a new progastrin-releasing peptide (ProGRP) immunoassay across Europe and China.

BACKGROUND: We performed a multicenter evaluation of the Elecsys® progastrin-releasing peptide (ProGRP) immunoassay in Europe and China. METHODS: The assay was evaluated at three European and two Chinese sites by imprecision, stability, method comparison and differentiation potential in lung cancer. RESULTS: Intermediate imprecision across five analyte concentrations ranged from 2.2% to 6.0% coefficient of variation. Good stability for plasma and serum samples was shown for various storage conditions. There was excellent correlation between the Elecsys® and ARCHITECT assays in plasma (slope 1.02, intercept -2.72pg/mL). The Elecsys® assay also showed good correlation between serum and plasma samples (slope 0.93, intercept 2.35pg/mL; correlation coefficient 0.97). ProGRP differentiated small-cell and non-small-cell lung cancer (NSCLC; area under the curve 0.90, 95% CI 0.87-0.93; 78.3% sensitivity, 95% specificity; at 84pg/mL), with no relevant effects of ethnicity, age, gender or smoking. Median ProGRP concentrations were low in benign diseases (38pg/mL), other malignancies (40pg/mL) or NSCLC (39pg/mL), except chronic kidney disease above stage 3 (>100pg/mL). CONCLUSIONS: Increased stability of the Elecsys® ProGRP assay in serum and plasma offers clear benefits over existing assays. This first evaluation of a ProGRP assay in China demonstrated comparable differentiation potential among different ethnicities.