Intra- and inter-cycle variability of anti-Müllerian hormone (AMH) levels in healthy women during non-consecutive menstrual cycles: the BICYCLE study.

OBJECTIVES: Determine variability of serum anti-Müllerian hormone (AMH) levels during ovulatory menstrual cycles between different women (inter-participant), between non-consecutive cycles (inter-cycle) and within a single cycle (intra-cycle) in healthy women. METHODS: Eligible participants were women aged 18-40 years with regular ovulatory menstrual cycles. Serum samples were collected every second day during two non-consecutive menstrual cycles. AMH levels were measured in triplicate using the Elecsys® AMH Plus immunoassay (Roche Diagnostics). AMH level variability was evaluated using mixed-effects periodic regression models based on Fourier series. The mesor was calculated to evaluate inter-participant and inter-cycle variability. Inter- and intra-cycle variability was evaluated using peak-to-peak amplitudes. Separation of biological and analytical coefficients of variation (CVs) was determined by analysing two remeasured AMH levels (with and without original AMH levels). RESULTS: A total of 47 women were included in the analysis (42 assessed over two cycles; five one cycle only). CV of unexplained biological variability was 9.61%; analytical variability was 3.46%. Inter-participant variability, given by time-series plots of AMH levels, was greater than inter-cycle variability. Between individual participants, both mesor and peak-to-peak amplitudes proved variable. In addition, for each participant, intra-cycle variability was higher than inter-cycle variability. CONCLUSIONS: Inter-participant and intra-cycle variability of AMH levels were greater than inter-cycle variability. Unexplained biological variability was higher than analytical variability using the Elecsys AMH Plus immunoassay. Understanding variability in AMH levels may aid in understanding differences in availability of antral ovarian follicles during the menstrual cycle, which may be beneficial in designing gonadotropin dosage for assisted reproductive technology.

Selection of within-run quality control rules for laboratory biomarkers.

In order to release correct biomarker results of a laboratory test, it is a regulatory requirement to apply quality control standards for controlling analytical errors. Releasing an incorrect test result might lead to wrong diagnosis or treatment of a patient in medical decision-making. In laboratory medicine, one of the means to control analytical errors is statistical process control procedures proposed by James O. Westgard and his coworkers nowadays known as "Westgard rules." To judge their performance for discriminating in-control from out-of-control processes, power curves are used. In this article, we describe functions for the power curves of the within-run Westgard rules. Based on these power curves, we use a benchmark approach for selecting a quality control procedure out of the set of Westgard rules. It is shown that two graphical procedures proposed by Westgard and his coworkers can be reduced to this benchmark approach. Besides, a commonly used measure in laboratory medicine for describing out-of-control processes is critically examined revealing the threat of selecting too optimistic quality control rules.

Levels of CXCL13 and sICAM-1 correlate with disease activity score in patients with rheumatoid arthritis treated with tocilizumab.

BACKGROUND: Tocilizumab (TCZ), a humanized monoclonal antibody against the interleukin-6 receptor, has been proven to be a safe and effective treatment for rheumatoid arthritis (RA). Because RA is a heterogenous disease and patient response to treatments can vary, identifying characteristics that predict which patients are more likely to respond to TCZ is important for optimal patient care. Serum levels of C-X-C motif chemokine ligand 13 (CXCL13) and soluble intercellular adhesion molecule-1 (sICAM-1) have been associated with response to TCZ in patients with RA. OBJECTIVES: To evaluate the association of CXCL13 and sICAM-1 with disease activity and response to TCZ in patients with early RA and those with inadequate response to disease-modifying antirheumatic drugs (DMARD-IR). METHODS: Baseline and week 24 serum CXCL13 and sICAM-1 levels were measured using available patient samples from the FUNCTION (early RA) and LITHE (DMARD-IR) trials. Correlations between CXCL13 and sICAM-1 levels and Disease Activity Score in 28 joints calculated with erythrocyte sedimentation rate (DAS28-ESR) at baseline and between change in CXCL13 and sICAM-1 and change in DAS28-ESR at week 24 were estimated. CXCL13 and sICAM-1 changes from baseline to week 24 were compared between treatment arms. The effects of TCZ treatment and baseline DAS28-ESR, CXCL13 and sICAM-1 levels on DAS28-ESR remission and 50% improvement per the American College of Rheumatology (ACR50) response at week 24 were determined. RESULTS: Overall, 458 patients from FUNCTION and 287 patients from LITHE were included. Correlation of baseline serum CXCL13 and sICAM-1 levels with DAS28-ESR was weak to moderate. CXCL13 and sICAM-1 levels decreased significantly at week 24 in TCZ-treated patients in both the early-RA and DMARD-IR populations. CXCL13 and sICAM-1 changes correlated moderately to weakly with DAS28-ESR changes at week 24 in both populations. The treatment regimen, but not baseline CXCL13 and sICAM-1 levels, had a significant effect on the likelihood of DAS28-ESR remission and ACR50 response. CONCLUSIONS: Although CXCL13 and sICAM-1 are modestly associated with RA disease activity, they do not predict response to TCZ in all RA populations.

Levels of CXCL13 and sICAM-1 correlate with disease activity score in patients with rheumatoid arthritis treated with tocilizumab

Abstract Background: Tocilizumab (TCZ), a humanized monoclonal antibody against the interleukin-6 receptor, has been proven to be a safe and effective treatment for rheumatoid arthritis (RA). Because RA is a heterogenous disease and patient response to treatments can vary, identifying characteristics that predict which patients are more likely to respond to TCZ is important for optimal patient care. Serum levels of C-X-C motif chemokine ligand 13 (CXCL13) and soluble intercellular adhesion molecule-1 (sICAM-1) have been associated with response to TCZ in patients with RA. Objectives: To evaluate the association of CXCL13 and sICAM-1 with disease activity and response to TCZ in patients with early RA and those with inadequate response to disease-modifying antirheumatic drugs (DMARD-IR). Methods: Baseline and week 24 serum CXCL13 and sICAM-1 levels were measured using available patient samples from the FUNCTION (early RA) and LITHE (DMARD-IR) trials. Correlations between CXCL13 and sICAM-1 levels and Disease Activity Score in 28 joints calculated with erythrocyte sedimentation rate (DAS28-ESR) at baseline and between change in CXCL13 and sICAM-1 and change in DAS28-ESR at week 24 were estimated. CXCL13 and sICAM-1 changes from baseline to week 24 were compared between treatment arms. The effects of TCZ treatment and baseline DAS28-ESR, CXCL13 and sICAM-1 levels on DAS28-ESR remission and 50% improvement per the American College of Rheumatology (ACR50) response at week 24 were determined. Results: Overall, 458 patients from FUNCTION and 287 patients from LITHE were included. Correlation of baseline serum CXCL13 and sICAM-1 levels with DAS28-ESR was weak to moderate. CXCL13 and sICAM-1 levels decreased significantly at week 24 in TCZ-treated patients in both the early-RA and DMARD-IR populations. CXCL13 and sICAM-1 changes correlated moderately to weakly with DAS28-ESR changes at week 24 in both populations. The treatment regimen, but not baseline CXCL13 and sICAM-1 levels, had a significant effect on the likelihood of DAS28-ESR remission and ACR50 response. Conclusions: Although CXCL13 and sICAM-1 are modestly associated with RA disease activity, they do not predict response to TCZ in all RA populations.

KRAS exon 2 mutations influence activity of regorafenib in an SW48-based disease model of colorectal cancer.

AIM: To investigate the impact of KRAS mutation variants on the activity of regorafenib in SW48 colorectal cancer cells. MATERIALS & METHODS: Activity of regorafenib was evaluated in isogenic SW48 KRAS wild-type (WT) and mutant cells. Subcutaneous xenografts (KRAS WT and G12C mutant variants) in NOD/SCID mice were analyzed to elucidate the effect of regorafenib treatment in vivo. RESULTS: Compared with KRAS WT cells, all mutant variants seemed associated with some degree of resistance to regorafenib-treatment in vitro. In vivo, activation of apoptosis (TUNEL) and reduction of proliferation (Ki67) after treatment with regorafenib were more pronounced in KRAS WT tumors as compared with G12C variants. CONCLUSION: In SW48 cells, exon 2 mutations of the KRAS gene may influence antitumor effects of regorafenib.

Surrogate endpoints in second-line treatment for mCRC: a systematic literature-based analysis from 23 randomised trials.

PURPOSE: To evaluate progression-free survival (PFS), overall response rate (ORR) and disease control rate (DCR) as potential surrogate endpoints (SEP) for overall survival (OS) in second-line treatment for metastatic colorectal cancer (mCRC). METHODS: A systematic literature search of randomised trials of second-line chemotherapy for mCRC reported from January 2000 to July 2013 was performed. Correlation coefficients weighted by number of patients in the treatment arms between median PFS, ORR and DCR with median OS were estimated. RESULTS: Twenty-three trials reflecting 10 800 patients met the inclusion criteria. Median PFS and OS across all trials were 4.5 months and 11.5 months and median ORR and DCR were 11.4% and 65%, respectively. PFS showed moderate correlation with OS [RPFS = 0.73; 95% confidence interval (CI) 0.61-0.82]. In contrast, ORR only weakly correlated with OS (RORR = 0.58; 95% CI 0.38-0.72, n = 22). Despite a small number of studies (n = 10) reporting on DCR, moderate correlation with OS was observed (RDCR = 0.74; 95% CI 0.56-0.86). CONCLUSION: Based on the available trial-level data, PFS may serve as an appropriate SEP in second-line chemotherapy for mCRC. A small number of studies revealed moderate correlation of DCR with OS that justifies further investigation.

Quantification of anandamide and 2-arachidonoylglycerol plasma levels to examine potential influences of tetrahydrocannabinol application on the endocannabinoid system in humans.

The effects of tetrahydrocannabinol (THC) and endogenous cannabinoids (endocannabinoids, ECs) are both mediated by activation of the cannabinoid receptors CB1 and CB2. Exogenous activation of these receptors by THC could therefore alter EC levels. We tested this hypothesis in healthy volunteers (n = 25) who received a large intravenous dose of THC (0.10 mg/kg). Effects on the EC system were quantified by serial measurements of plasma ECs after THC administration. Eleven blood samples were drawn during the first 5 h after THC administration and two more samples after 24 and 48 h. THC, its metabolites THC-OH (biologically active) and THC-COOH (non-active), and the ECs anandamide and 2-arachidonoylglycerol (2-AG) were quantified by liquid chromatography-mass spectrometry. EC-plasma levels showed a biphasic response after THC injection reaching maximal values at 30 min. Anandamide increased slightly from 0.58 ± 0.21 ng/ml at baseline to 0.64 ± 0.24 ng/ml (p < 0.05) and 2-AG from 7.60 ± 4.30 ng/ml to 9.50 ± 5.90 ng/ml (p < 0.05). After reaching maximal concentrations, EC plasma levels decreased markedly to a nadir of 300 min after THC administration (to 0.32 ± 0.15 ng/ml for anandamide and to 5.50 ± 3.01 ng/ml for 2-AG, p < 0.05). EC plasma concentrations returned to near baseline levels until 48 h after the experiment. THC (0.76 ± 0.16 ng/ml) and THC-OH (0.36 ± 0.17 ng/ml) were still measurable at 24 h and remained detectible until 48 h after THC administration. Although the underlying mechanism is not clear, high doses of intravenous THC appear to influence endogenous cannabinoid concentrations and presumably EC-signalling.

Progression-free survival as a surrogate endpoint for median overall survival in metastatic colorectal cancer: literature-based analysis from 50 randomized first-line trials.

PURPOSE: To evaluate progression-free survival (PFS) as a potential surrogate endpoint (SEP) for overall survival (OS) in metastatic colorectal cancer (mCRC) with a focus on applicability to trials containing targeted therapy with anti-VEGF- or anti-EGF receptor (EGFR)-directed monoclonal antibodies. EXPERIMENTAL DESIGN: A systematic literature search of randomized trials of first-line chemotherapy for mCRC reported from January 2000 to January 2012 was conducted. Adjusted weighted linear regression was used to calculate correlations within PFS and OS (endpoints; R(EP)) and between treatment effects on PFS and on OS (treatment effects; R(TE)). RESULTS: Fifty trials reflecting 22,736 patients met the inclusion criteria. Correlation between treatment effects on PFS and OS and between the endpoints PFS and OS was high across all studies (R(TE) = 0.87, R(EP) = 0.86). This was also observed in chemotherapy-only trials (R(TE) = 0.93, R(EP) = 0.81) but less so for trials containing monoclonal antibodies (R(TE) = 0.47; R(EP) = 0.52). Limiting the analysis to bevacizumab-based studies (11 trials, 3,310 patients) again yielded high correlations between treatment effects on PFS and on OS (R(TE) = 0.84), whereas correlation within PFS and OS was low (R(EP) = 0.45). In 7 trials (1,335 patients) investigating cetuximab- or panitumumab-based studies, contrasting correlations with very wide confidence intervals were observed (R(TE) = 0.28; R(EP) = 0.96). CONCLUSIONS: PFS showed consistently high correlation with OS of an order that would justify its use as an SEP in chemotherapy regimens. For validation of surrogacy in anti-VEGF and anti-EGFR-directed therapies, further research and a larger set of trials is needed.

Two-marker combinations for preoperative discrimination of benign and malignant ovarian masses.

BACKGROUND: When caring for patients with ovarian neoplasms, correct preoperative discrimination of benign and malignant disease is deemed vital. In this study, we tested serum biomarkers' alone and in combination, to achieve this aim. MATERIALS AND METHODS: We measured the concentrations of Cancer Antigen (CA)-125, CA15-3, CA27-29, Carcinoembryonic Antigen (CEA), CA19-9, human chorionic gonadotropin (hCG), Placental Protein (PP)1490, CA72-4, galectin-3, galectin-1 and Human epididymis protein (HE)4 in sera of 133 patients with pelvic masses by ELISA and correlated the results to subsequent histology. We used the area under the curve (AUC) of biomarkers and their combinations and calculated the 95% confidence intervals by using casewise resampling. RESULTS: The best single biomarkers were CA-125 (sensitivity and AUC) and HE4 (specificity). Combinations with HE4 and CA19-9 improved the predictive power of CA-125. The best discrimination was achieved by the combination of CA-125 and HE4, with an AUC of 0.961. CONCLUSION: A combination of CA-125 with HE4 could facilitate the identification of women at risk for ovarian cancer.

Cetuximab-based or bevacizumab-based first-line treatment in patients with KRAS p.G13D-mutated metastatic colorectal cancer: a pooled analysis.

KRAS p.G13D mutant metastatic colorectal cancer (mCRC) has been identified as representing a cetuximab-sensitive subtype of KRAS mutant mCRC. This analysis aims to answer the question of whether first-line treatment of p.G13D mCRCs should include cetuximab or bevacizumab. Fifty-four patients with p.G13D mutant mCRC were pooled in this analysis. All patients underwent systemic first-line treatment with a fluoropyrimidine and oxaliplatin/irinotecan that was combined with either cetuximab or bevacizumab. The analysis of cetuximab-based and bevacizumab-based regimens in mCRC patients with p.G13D-mutated tumours indicated comparable data for the overall response rate (58 vs. 57%) and progression-free survival (8.0 vs. 8.7 months; hazard ratio: 0.96, P=0.9). Overall survival (OS) was 20.1 months in patients treated with cetuximab-based first-line therapy compared with 14.9 months in patients receiving bevacizumab-containing regimens (hazard ratio: 0.70, P=0.29). Logistic regressions modelling OS revealed oxaliplatin-based first-line treatment to correlate with a poor outcome (P=0.03). Moreover, a strong trend in favour of capecitabine compared with infusional 5-FU (P=0.06) was observed. Response to treatment correlated with OS in patients receiving cetuximab-based, but not bevacizumab-based regimens. This retrospective pooled analysis suggests comparable efficacy of cetuximab-based and bevacizumab-based first-line therapy in patients with p.G13D mutant mCRC. The combination with capecitabine and irinotecan was associated with a more favourable outcome compared with infusional 5-FU and oxaliplatin.

Hyperdense basilar artery sign-a reliable sign of basilar artery occlusion.

INTRODUCTION: We aimed to investigate the value of the hyperdense basilar artery (HBA) sign and of basilar artery (BA) attenuation measurements as predictors of basilar artery occlusion (BAO) on nonenhanced cranial CT (NECT). METHODS: Forty-one consecutive patients with proven BAO in CT angiography, who had undergone NECT for initial evaluation (30 males, 11 females) were retrospectively included. Another 41 age-matched patients without BAO were included as a control group. The NECT scans of both groups were assessed by three independent blinded readers (staff, fellow, and resident) in a randomized reading order using a standardized semiquantitative questionnaire. Visual BA hyperdensity, including the presence of HBA sign (hyperdensity scores of 4 and 5/5), was assessed, quantitative BA attenuation was measured in a region of interest (ROI), and diagnosis of BAO was made before and after ROI measurements. For statistical analysis, multivariate mixed effects models, likelihood ratio tests, and receiver operating characteristics techniques were applied. RESULTS: HBA sign had a relatively low sensitivity (60.98-65.85%), specificity (70.73-90.24%), and accuracy (65.85-75.61%) for the presence/absence of BAO on NECT. Optimal cut-off points were 40-42 HU (sensitivity, 68.29-78.05%; specificity, 75.61-82.93%; accuracy, 74.39-80.49%). CONCLUSION: In basilar artery occlusion, quantitative measurement of BA attenuation can slightly improve the diagnostic predictiveness of NECT. However, even with optimal cut-off values, the sensitivity is too low to serve as the sole diagnostic decision-making tool.

Analysis for prognostic factors of 60-day mortality: evaluation of an irinotecan-based phase III trial performed in the first-line treatment of metastatic colorectal cancer.

BACKGROUND: Mortality rates in published irinotecan-based trials range between 1.7% and 5.0%. This analysis aimed to evaluate clinical and histopathologic factors associated with 60-day mortality in first-line therapy for metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Sixty-day all-cause and disease-specific mortality rates from 479 patients who participated in a randomized phase III study comparing FUFIRI (5-fluorouracil [5-FU], leucovorin, irinotecan) (n = 238) vs. mIROX (modified irinotecan plus oxaliplatin (n = 241) were evaluated for association with prognostic factors such as platelet counts, alkaline phosphatase (AP) levels, white blood cell (WBC) counts, hemoglobin values, lactate dehydrogenase (LDH) levels, carcinoembryonic antigen (CEA) levels, and several other baseline parameters using univariate and multivariate logistic regression analyses applied to patients combined from both treatment groups. RESULTS: The all-cause 60-day mortality rate was 5.0% (24/479). Thirteen patients (5.5%) in the FUFIRI arm died within the first 60 days of treatment compared with 11 (4.6%) patients in the mIROX arm (P = .68). Among the 24 patients in both treatment arms, mortality was qualified as disease related in 15 (63%) patients and treatment related in 7 (29%) patients (P = .695). In multivariate analyses, high LDH levels (P = .010) and an elevated WBC count (P = .006) remained as significant independent prognostic factors. Low Karnofsky performance status (KPS) showed a strong trend but failed to reach statistical significance (P = .057) as did AP levels and the number of metastatic sites. CONCLUSION: In this study 63% of the early deaths were disease related, whereas only 29% were possibly related to study medication. Independent prognostic factors for early mortality were LDH levels and WBC counts. KPS showed a strong trend in the multivariate analysis. Future investigation may consider LDH levels and WBC counts for exclusion criteria.

Mirror movements in healthy humans across the lifespan: effects of development and ageing.

AIM: mirror movements are a transient phenomenon during childhood, which decrease in intensity with motor development. An increasing inhibitory competence resulting in the ability of movement lateralization is thought to be the underlying mechanism. We aimed to quantify unintended mirror movements systematically across the lifespan and to investigate the influences of age, sex, handedness, and task frequency. METHOD: a total of 236 participants (127 females, 109 males; 216 right-handed, 20 left-handed; age range 3-96y, median 25y 8mo) first performed four clinical routine tests while mirror movements were rated by the observer. They were then asked to hold a force transducer in each hand between the thumb and index finger and to perform oscillatory grip force changes in one hand, while the other hand had to prevent the force transducer from dropping. RESULTS: age showed a strong nonlinear effect on the mirror-movement ratio (the amplitude ratio of the mirror and active hand, adjusted by the respective maximum grip force). Initially, there was a steep decline in the mirror-movement ratio during childhood and adolescence, followed by a gradual rise during adulthood. Males had lower mirror-movement ratios than females. The high-frequency condition triggered lower mirror-movement ratios. No significant differences of mirror movements between dominant and non-dominant hand, or left- and right-handed participants, were found. INTERPRETATION: this study provides, for the first time to our knowledge, normative values of mirror movements across the lifespan that can aid differentiation between physiological and pathological mirror movements.