Patch Testing Pearls.

Dermatitis is one of the most common illnesses encountered by healthcare providers and the causes are numerous. Contact dermatitis is the form of dermatitis resulting from contact with the environment, and it may be either irritant or allergic in nature. Patch testing has been the gold standard for diagnosis of allergic contact dermatitis since its formal description over 100 years ago by Jadassohn. While this diagnostic tool may seem simple to us today, there are numerous potential points for error that the practitioner must keep in mind. Patient selection, technique of patch test placement, allergen selection, patch test reading and interpretation, and patient management all must be considered. To simply apply a given set of test allergens indiscriminately and not be prepared to interpret the results accurately with patient education and management in mind would be a great failure. Conversely, with experience and the proper knowledge base some of the most complex dermatitis questions can be answered.

Training improves the interobserver agreement of the expert positron emission tomography review panel in primary mediastinal B-cell lymphoma: interim analysis in the ongoing International Extranodal Lymphoma Study Group-37 study.

The International Extranodal Lymphoma Study Group (IELSG)-37 is a prospective randomized trial assessing the role of consolidation mediastinal radiotherapy after immunochemotherapy to patients with newly diagnosed primary mediastinal large B-cell lymphoma (PMBCL). It is a positron emission tomography (PET) response-guided study where patients obtaining a complete metabolic response on an end-of-therapy PET-computed tomography (CT) scan evaluated by a central review are randomized to receive radiotherapy or no further treatment. The aims of this study were to measure agreement between reviewers reporting PET-CT scans for this trial and to determine the effect of training upon concordance rates. The review panel comprised 6 experienced nuclear physicians who read PET-CT scans using the 5-point Deauville scale. Interobserver agreement (IOA) was measured at 4 time points: after a blinded review of a "training set" of 20 patients with PMBCL from the previous IELSG-26 study (phase 1); after the first 10 clinical cases enrolled in the IELSG-37 (phase 2); and after 2 further groups of 50 (phase 3) and 40 clinical cases (phase 4). After feedback from the training set and the first 10 cases, a meeting was held to discuss interpretation, and a detailed set of instructions for the review procedure was agreed and acted upon. Between 2012 and 2014, the first 100 patients were reviewed. Using Deauville score 3 as the cutoff for a complete metabolic response, the overall IOA among the reviewers was good (Krippendorff α = 0.72.) The binary concordance between pairs of reviewers (Cohen κ) ranged from 0.60 to 0.78. The IOA, initially moderate, improved progressively from phase 1 to 4 (Krippendorff α from 0.53 to 0.81; Cohen κ from 0.35-0.72 to 0.77-0.87). Our experience indicates that the agreement among "expert" nuclear physicians reporting PMBCL, even using standardized criteria, was only moderate when the study began. However, agreement improved using a harmonization process, which included a training exercise with discussion of points leading to disagreement and compiling practical rules to sit alongside commonly adopted interpretation criteria.

Improved inter-observer agreement of an expert review panel in an oncology treatment trial--Insights from a structured interventional process.

PURPOSE: Oncologic imaging is a key for successful cancer treatment. While the quality assurance (QA) of image acquisition protocols has already been focussed, QA of reading and reporting offers still room for improvement. The latter was addressed in the context of a prospective multicentre trial on fluoro-deoxyglucose (FDG)-positron-emission tomography (PET)/CT-based chemoradiotherapy for locally advanced non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: An expert panel was prospectively installed performing blinded reviews of mediastinal NSCLC involvement in FDG-PET/CT. Due to a high initial reporting inter-observer disagreement, the independent data monitoring committee (IDMC) triggered an interventional harmonisation process, which overall involved 11 experts uttering 6855 blinded diagnostic statements. After assessing the baseline inter-observer agreement (IOA) of a blinded re-review (phase 1), a discussion process led to improved reading criteria (phase 2). Those underwent a validation study (phase 3) and were then implemented into the study routine. After 2 months (phase 4) and 1 year (phase 5), the IOA was reassessed. RESULTS: The initial overall IOA was moderate (kappa 0.52 CT; 0.53 PET). After improvement of reading criteria, the kappa values improved substantially (kappa 0.61 CT; 0.66 PET), which was retained until the late reassessment (kappa 0.71 CT; 0.67 PET). Subjective uncertainty was highly predictive for low IOA. CONCLUSION: The IOA of an expert panel was significantly improved by a structured interventional harmonisation process which could be a model for future clinical trials. Furthermore, the low IOA in reporting nodal involvement in NSCLC may bear consequences for individual patient care.