Clinical Performance of the Idylla MSI Test for a Rapid Assessment of the DNA Microsatellite Status in Human Colorectal Cancer.

In this study, the clinical performance of the Idylla MSI test (investigational use only) was evaluated in 330 colorectal carcinoma samples (all stages). This test is fully automated, from formalin-fixed, paraffin-embedded slide to result, and gives a result in <2.5 hours. Compared with the Promega MSI Analysis System version 1.2, an overall agreement, sensitivity, and specificity of 99.7%, 98.7%, and 100%, respectively, was reached. Whereas seven samples were invalid with the Promega MSI Analysis System, only two were invalid with the Idylla MSI test. Compared with the historical immunohistochemistry (IHC) data, overall agreement, sensitivity, and specificity of 98.7%, 94.4%, and 100%, respectively, were observed. Tumor mutation burden analysis of the discordant IHC cases was in favor of the Idylla MSI test result in three of the four samples. Furthermore, for those cases where the IHC data were invalid or hard to interpret because sole loss of one DNA mismatch repair deficiency marker was observed, Idylla MSI test results were always valid and accurate. Herein, the Idylla MSI test has been shown to be an accurate, fast screening assay for the detection of microsatellite status in colorectal cancer patients, with a low number of invalid results.

A stitch in time saves nine: external quality assessment rounds demonstrate improved quality of biomarker analysis in lung cancer.

Biomarker analysis has become routine practice in the treatment of non-small cell lung cancer (NSCLC). To ensure high quality testing, participation to external quality assessment (EQA) schemes is essential. This article provides a longitudinal overview of the EQA performance for EGFR, ALK, and ROS1 analyses in NSCLC between 2012 and 2015. The four scheme years were organized by the European Society of Pathology according to the ISO 17043 standard. Participants were asked to analyze the provided tissue using their routine procedures. Analysis scores improved for individual laboratories upon participation to more EQA schemes, except for ROS1 immunohistochemistry (IHC). For EGFR analysis, scheme error rates were 18.8%, 14.1% and 7.5% in 2013, 2014 and 2015 respectively. For ALK testing, error rates decreased between 2012 and 2015 by 5.2%, 3.2% and 11.8% for the fluorescence in situ hybridization (FISH), FISH digital, and IHC subschemes, respectively. In contrast, for ROS1 error rates increased between 2014 and 2015 for FISH and IHC by 3.2% and 9.3%. Technical failures decreased over the years for all three markers. Results show that EQA contributes to an ameliorated performance for most predictive biomarkers in NSCLC. Room for improvement is still present, especially for ROS1 analysis.

Evaluation of [18F]CP18 as a Substrate-Based Apoptosis Imaging Agent for the Assessment of Early Treatment Response in Oncology.

PURPOSE: The substrate-based positron emission tomography (PET) tracer [18F]CP18 is capable of detecting the activity of caspase-3/7, two key executioner proteases in the apoptosis pathway, through selective cleavage of the ligand by the activated proteases and subsequent accumulation in apoptotic cells. Using an in vitro and in vivo model of colorectal cancer (CRC), we investigated whether [18F]CP18 tracer accumulation provides a measure for apoptosis and reliably reflects early treatment response to chemotherapeutics. PROCEDURES: [18F]CP18 cell uptake was assessed in treated Colo205 cells (saline, 5-fluorouracil (5-FU), irinotecan or their combination) and correlated with caspase-3/7 activity. [18F]CP18 imaging was performed in Colo205 xenografts, starting with a baseline µPET/micro X-ray computed tomography (​µCT) scan, followed by a 3-day treatment with saline (n = 5), 5-FU (low sensitivity, n = 4), irinotecan (high sensitivity, n = 5), or a combination of both (n = 7). The study was concluded with a second [18F]CP18 scan, 24 h after final treatment administration, followed by tumor removal for gamma counting (%ID/g) and for cleaved caspase-3 immunohistochemistry (apoptotic index/necrosis). Tumors were delineated on µCT images and, using the obtained volumes of interest, average percentage injected dose per cubic centimeter (%ID/cm3) was calculated from every µPET image. RESULTS: In vitro, [18F]CP18 cell uptake was positively correlated with caspase-3/7 activity (r = 0.59, p = 0.003). A drug-dependent increase in [18F]CP18 tumor uptake compared to baseline was observed in animals treated with 5-FU (+14 ± 25 %), irinotecan (+56 ± 54 %), and their combination (+158 ± 69 %, p = 0.002). %ID/cm3 showed a positive relationship with both %ID/g (r = 0.83, p < 0.0001) and the apoptotic index (r = 0.60, p = 0.004), but not with tumor necrosis (r = 0.22, p = 0.36). CONCLUSION: Both our in vitro and in vivo findings have shown the ability of [18F]CP18-PET to visualize therapy-induced cancer cell apoptosis and possibly serve as a biomarker for early therapy response.

The relevance of external quality assessment for molecular testing for ALK positive non-small cell lung cancer: results from two pilot rounds show room for optimization.

BACKGROUND AND PURPOSE: Molecular profiling should be performed on all advanced non-small cell lung cancer with non-squamous histology to allow treatment selection. Currently, this should include EGFR mutation testing and testing for ALK rearrangements. ROS1 is another emerging target. ALK rearrangement status is a critical biomarker to predict response to tyrosine kinase inhibitors such as crizotinib. To promote high quality testing in non-small cell lung cancer, the European Society of Pathology has introduced an external quality assessment scheme. This article summarizes the results of the first two pilot rounds organized in 2012-2013. MATERIALS AND METHODS: Tissue microarray slides consisting of cell-lines and resection specimens were distributed with the request for routine ALK testing using IHC or FISH. Participation in ALK FISH testing included the interpretation of four digital FISH images. RESULTS: Data from 173 different laboratories was obtained. Results demonstrate decreased error rates in the second round for both ALK FISH and ALK IHC, although the error rates were still high and the need for external quality assessment in laboratories performing ALK testing is evident. Error rates obtained by FISH were lower than by IHC. The lowest error rates were observed for the interpretation of digital FISH images. CONCLUSION: There was a large variety in FISH enumeration practices. Based on the results from this study, recommendations for the methodology, analysis, interpretation and result reporting were issued. External quality assessment is a crucial element to improve the quality of molecular testing.