Novel optical spectral transmission (OST)-guided versus conventionally disease activity-guided treatment: study protocol of a randomized clinical trial on guidance of a treat-to-target strategy for early rheumatoid arthritis.

BACKGROUND: Assessment of disease activity is a critical component of tight-control, treat-to-target treatment strategies of rheumatoid arthritis (RA). Recently, the HandScan has been validated as a novel method for objectively assessing RA disease activity in only 1.5 min, using optical spectral transmission (OST) in hands and wrists. We describe the protocol of a randomized controlled clinical trial (RCT) to investigate whether HandScan-guided treatment aimed at 'HandScan remission' (HandScan arm) is at least as effective as and more cost-effective than clinically guided treatment aimed at ACR/EULAR 2011 Boolean remission (DAS arm). METHODS/DESIGN: The study is a multi-center, double-blind, non-inferiority RCT of 18 months duration. Patients ≥ 18 years with newly diagnosed, disease-modifying antirheumatic drug (DMARD)-naïve RA according to the ACR 2010 classification criteria, will be randomized to the DAS arm or the HandScan arm. The efficacy of the arms will be compared by evaluating Health Assessment Questionnaire (HAQ) scores (primary outcome) after 18 months of DMARD therapy, aimed at remission. The equivalence margin in HAQ scores between study arms is 0.2. Secondary outcomes are differences in cost-effectiveness and radiographic joint damage between treatment arms. The non-inferiority sample size calculation to obtain a power of 80% at a one-sided p value of 0.05, with 10% dropouts, resulted in 61 patients per arm. In both arms, DMARD strategy will be intensified monthly according to predefined steps until remission is achieved; in both arms DMARDs and treatment steps are identical. If sustained remission, defined as remission that persists consistently over three consecutive months, is achieved, DMARD therapy will be tapered. DISCUSSION: The study protocol and the specifically designed decision-making software application allow for implementation of this RCT. To test a novel method of assessing disease activity and comparing (cost-)effectiveness with the contemporary method in treat-to-target DMARD strategies in early RA patients. TRIAL REGISTRATION: Dutch Trial Register, NTR6388. Registered on 6 April 2017 ( NL50026.041.14 ). Protocol version 3.0, 19-01-2017.

Can optical spectral transmission assess ultrasound-detected synovitis in hand osteoarthritis?

OBJECTIVE: To determine whether optical spectral transmission (OST) can be used to assess synovitis in hand and wrist joints of patients with hand osteoarthritis (OA). DESIGN: Hand and wrist joints of 47 primary hand OA patients with at least one clinically inflamed hand or wrist joint were assessed for synovitis by OST and ultrasound (US). Associations between standardized OST and US synovitis were studied in linear mixed effects models, across all joint types together and individually for wrist, proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints, and were adjusted for OA features that showed associations with US synovitis. Diagnostic performance was determined using receiver operator characteristic (ROC) curves analysis, with US as reference standard. RESULTS: Altogether, 6.7% of joints showed US synovitis. Statistically significant associations between OST scores and US synovitis were found for all joints combined (Δ0.37SD, p<0.001) and PIP joints (Δ0.81SD, p<0.001), but not for DIP (Δ0.14SD, p = 0.484) or wrist joints (Δ0.37SD, p = 0.178). All associations were independent of other OA features, i.e. osteophytes and dorsal vascularity. Analysis of diagnostic performance of OST, revealed an area under the ROC curve (AUC-ROC) of 0.74 for all joints together (p<0.001), 0.69 for PIP joints (p<0.001), 0.54 for DIP joints (p = 0.486), and 0.61 for wrist joints (p = 0.234). CONCLUSIONS: OST scores and US synovitis are statistically significantly associated, independent of osteophytes and dorsal vascularity. At this stage, OST performs fair in the assessment of synovitis in PIP joints of hand OA patients.

RAS pathway mutations as a predictive biomarker for treatment adaptation in pediatric B-cell precursor acute lymphoblastic leukemia.

RAS pathway mutations have been linked to relapse and chemotherapy resistance in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL). However, comprehensive data on the frequency and prognostic value of subclonal mutations in well-defined subgroups using highly sensitive and quantitative methods are lacking. Targeted deep sequencing of 13 RAS pathway genes was performed in 461 pediatric BCP-ALL cases at initial diagnosis and in 19 diagnosis-relapse pairs. Mutations were present in 44.2% of patients, with 24.1% carrying a clonal mutation. Mutation frequencies were highest in high hyperdiploid, infant t(4;11)-rearranged, BCR-ABL1-like and B-other cases (50-70%), whereas mutations were less frequent in ETV6-RUNX1-rearranged, and rare in TCF3-PBX1- and BCR-ABL1-rearranged cases (27-4%). RAS pathway-mutated cells were more resistant to prednisolone and vincristine ex vivo. Clonal, but not subclonal, mutations were linked to unfavorable outcome in standard- and high-risk-treated patients. At relapse, most RAS pathway mutations were clonal (9 of 10). RAS mutant cells were sensitive to the MEK inhibitor trametinib ex vivo, and trametinib sensitized resistant cells to prednisolone. We conclude that RAS pathway mutations are frequent, and that clonal, but not subclonal, mutations are associated with unfavorable risk parameters in newly diagnosed pediatric BCP-ALL. These mutations may designate patients eligible for MEK inhibitor treatment.

Technical feasibility of personalized articulating knee joint distraction for treatment of tibiofemoral osteoarthritis.

BACKGROUND: Knee osteoarthritis is a highly prevalent degenerative joint disorder characterized by joint tissue damage and pain. Knee joint distraction has been introduced as a joint preserving surgical procedure to postpone knee arthroplasty. An often used standard externally fixation device for distraction poses a burden to patients due to the absence of joint flexion during the 6weeks treatment. Therefore, a personalized articulating distraction device was developed. The aim of this study was to test technical feasibility of this device. METHODS: Based on an often applied rigid device, using equal bone pin positions and connectors, a hinge mechanism was developed consisting of a cam-following system for reproducing the complex joint-specific knee kinematics. In support, a device was developed for capturing the joint-specific sagittal plane articulation. The obtained kinematic data were translated into joint-specific cam shapes that were installed bilaterally in the hinge mechanism of the distraction device, as such providing personalized knee motion. Distraction of 5mm was performed within a range of motion of 30deg. joint flexion. Pre-clinical evaluation of the working principle was performed on human cadaveric legs and system stiffness characteristics were biomechanically evaluated. FINDINGS: The desired range of motion was obtained and distraction was maintained under physiologically representative loading. Moreover, the joint-specific approach demonstrated tolerance of deviations from anatomical and alignment origin during initial placement of the developed distraction device. INTERPRETATION: Articulation during knee distraction is considered technically feasible and has potential to decrease burden and improve acceptance of distraction therapy. Testing of clinical feasibility is warranted.

Automated cerebral infarct volume measurement in follow-up noncontrast CT scans of patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: Cerebral infarct volume as observed in follow-up CT is an important radiologic outcome measure of the effectiveness of treatment of patients with acute ischemic stroke. However, manual measurement of CIV is time-consuming and operator-dependent. The purpose of this study was to develop and evaluate a robust automated measurement of the CIV. MATERIALS AND METHODS: The CIV in early follow-up CT images of 34 consecutive patients with acute ischemic stroke was segmented with an automated intensity-based region-growing algorithm, which includes partial volume effect correction near the skull, midline determination, and ventricle and hemorrhage exclusion. Two observers manually delineated the CIV. Interobserver variability of the manual assessments and the accuracy of the automated method were evaluated by using the Pearson correlation, Bland-Altman analysis, and Dice coefficients. The accuracy was defined as the correlation with the manual assessment as a reference standard. RESULTS: The Pearson correlation for the automated method compared with the reference standard was similar to the manual correlation (R = 0.98). The accuracy of the automated method was excellent with a mean difference of 0.5 mL with limits of agreement of -38.0-39.1 mL, which were more consistent than the interobserver variability of the 2 observers (-40.9-44.1 mL). However, the Dice coefficients were higher for the manual delineation. CONCLUSIONS: The automated method showed a strong correlation and accuracy with the manual reference measurement. This approach has the potential to become the standard in assessing the infarct volume as a secondary outcome measure for evaluating the effectiveness of treatment.