Programmed Cell Death Ligand 1 Pathologist Training in the Time of COVID-19: Our Experience using a Digital Solution.

The COVID-19 pandemic presented numerous challenges to the continuity of programmed cell death ligand 1 (PD-L1) assay training events conducted by our organization. Under typical conditions, these training events are face-to-face affairs, where participants are trained to assay algorithms on glass slides during multi-headed scope sessions. Social distancing measures undertaken to slow pandemic spread necessitated the adaptation of our training methods to facilitate assay training and subsequent continuation of clinical trials. The present report details the creation and use of the Roche pathology training portal (PTP) that allowed for remote training to diagnostic assay algorithms. The PTP is a web-based system comprised of a learning management system (LMS) coupled to an image management system (IMS). Whole slide images (WSIs) were produced using a DP200 instrument (Roche, Pleasanton, CA) and these scan files were then uploaded to an IMS. Courses were created on the LMS using annotated WSIs that were shared with enrolled pathologists worldwide during assay training events. These courses culminated in assay certification examinations, where pathologists evaluated test-case WSIs and evaluated these cases within the LMS. Trainee submissions were analyzed for pass/fail status by comparing user data entries with consensus scores on these test-case WSIs. To date, 47 pathologist trainings have occurred and of these, 44 have successfully passed the associated assay certification exam on the first attempt (93% 1st-try pass rate). The PTP allowed roche to continue training sites during the COVID-19 pandemic, and these early results demonstrate the capability of this digital solution regarding PD-L1 diagnostic assay training events.

A noninterventional, multinational study to assess PD-L1 expression in cytological and histological lung cancer specimens.

BACKGROUND: The diagnosis of advanced lung cancer is made with minimally invasive procedures. This often results in the availability of cytological material only for subtype determination and companion diagnostic testing, with the latter being technically and clinically validated on histological material only. Thus, the primary objective of the MO29978 clinical study was to assess programmed death ligand 1 (PD-L1) protein expression on cytology samples as surrogates for histology samples in patients with lung cancer. METHODS: Formalin-fixed, paraffin-embedded histological samples and cytological cell blocks from 190 patients were analyzed with immunohistochemical assays using the rabbit monoclonal anti-PD-L1 antibody clones SP142 and SP263. PD-L1 expression was quantified on both tumor cells (TC) and tumor-infiltrating immune cells (IC). Overall concordance, sensitivity, specificity, and accuracy, with a 1% cutoff used for both assays, were assessed for PD-L1 expression on TC and IC. RESULTS: In non-small cell lung cancer histology and cytology samples measured with the PD-L1 (SP142) antibody (n = 173), the intraclass correlation coefficients were 0.40 and 0.06 on TC and IC, respectively. With SP142 and SP263, accuracies of 74.1% for TC and 51.9% for IC and accuracies of 75.2% for TC and 61.2% for IC, respectively, were reported. CONCLUSIONS: Overall, this study has demonstrated that PD-L1 analysis on TC is feasible in cytological material, but quantification is challenging. Tumor tissue should be preferred over cell block cytology for PD-L1 immunohistochemical analysis unless laboratories have validated their cytology preanalytical approaches and demonstrated the comparability of histology and cytology for TC PD-L1 results.

In situ analysis of FGFR2 mRNA and comparison with FGFR2 gene copy number by dual-color in situ hybridization in a large cohort of gastric cancer patients.

BACKGROUND: Fibroblast growth factor receptor (FGFR2) has been proposed as a target in gastric cancer. However, appropriate methods to select patients for anti-FGFR2 therapies have not yet been established. METHODS: We used in situ techniques to investigate FGFR2 mRNA expression and gene amplification in a large cohort of 1036 Japanese gastric cancer patients. FGFR2 mRNA expression was determined by RNAscope. FGFR2 gene amplification was determined by dual-color in situ hybridization (DISH). RESULTS: We successfully analyzed 578 and 718 samples by DISH and RNAscope, respectively; 2% (12/578) showed strong FGFR2 gene amplification (FGFR2:CEN10 >10); moderate FGFR2 gene amplification (FGFR2:CEN10 <10; ≥2) was detected in 8% (47/578); and high FGFR2 mRNA expression of score 4 (>10 dots/cell and >10% of positive cells with dot clusters under a 20× objective) was seen in 4% (29/718). For 468 samples, both mRNA and DISH data were available. FGFR2 mRNA expression levels were associated with gene amplification; FGFR2 mRNA levels were highest in the highly amplified samples (n = 12). All highly amplified samples showed very strong FGFR2 mRNA expression (dense clusters of the signal visible under a 1× objective). Patients with very strong FGFR2 mRNA expression showed more homogeneous FGFR2 mRNA expression compared to patients with lower FGFGR2 mRNA expression. Gastric cancer patients with tumors that had an FGFR2 mRNA expression score of 4 had shorter RFS compared with score 0-3 patients. CONCLUSION: RNAscope and DISH are suitable methods to evaluate FGFR2 status in gastric cancer. Formalin-fixed paraffin-embedded (FFPE) tissue slides allowed evaluation of the intratumor heterogeneity of these FGFR2 biomarkers.

Evaluating clinical and prognostic implications of Glypican-3 in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most deadly cancers worldwide. In patients with HCC, histopathogical differentiation is an important indicator of prognosis; however, because determination of HCC differentiation is difficult, the recently described immunohistochemical (IHC) marker glypican3 (GPC3) might assist in HCC prognostication.The goal of our study was to investigate GPC3's IHC staining pattern and define the relationship between its expression and patients' clinicopathologic features and overall survival. We retrieved clinical parameters from 101 pathologically diagnosed HCC patients' medical records and classified these patients into 4 clinical score categories (0-3) based on increasing GPC3 staining intensity and the percentage of stained tumor cells in their resection and biopsy specimens. Histopathological samples were well, moderately, and poorly differentiated in 33, 22, and 12 patients, respectively, and the GPC3 expression rate was 63%, 86%, and 92%,respectively. The median overall survival was 49.9 months (confidence interval (CI): 35.3-64.6 months) for clinical scores 0-1 and 30.7 months (CI: 19.4-41.9 months) for clinical scores 2-3. This difference was not statistically significant (P = .06) but showed a strong trend. In conclusion, a greater GPC3 expression is associated with a worse HCC prognosis and may be a promising prognostic marker.

Validation of an electronic program for pathologist training in the interpretation of a complex companion diagnostic immunohistochemical assay.

Companion diagnostics assay interpretation can select patients with the greatest targeted therapy benefits. We present the results from a prospective study demonstrating that pathologists can effectively learn immunohistochemical assay-interpretation skills from digital image-based electronic training (e-training). In this study, e-training was used to train board-certified pathologists to evaluate non-small cell lung carcinoma for eligibility for treatment with onartuzumab, a MET-inhibiting agent. The training program mimicked the live training that was previously validated in clinical trials for onartuzumab. A digital interface was developed for pathologists to review high-resolution, static images of stained slides. Sixty-four pathologists practicing in the United States enrolled while blinded to the type of training. After training, both groups completed a mandatory final test using glass slides. The results indicated both training modalities to be effective. Overall, 80.6% of e-trainees and 72.7% of live trainees achieved passing scores (at least 85%) on the final test. All study participants reported that their training experience was "good" and that they had received sufficient information to determine the adequacy of case slide staining to score each case. This study established that an e-training program conducted under highly controlled conditions can provide pathologists with the skills necessary to interpret a complex assay and that these skills can be equivalent to those achieved with face-to-face training using conventional microscopy. Programs of this type are scalable for global distribution and offer pathologists the potential for readily accessible and robust training in new companion diagnostic assays linked to novel, targeted, adjuvant therapies for cancer patients.

Evolution of brain imaging instrumentation.

Computed tomography (CT) and static magnetic resonance imaging (MRI) are now the most common imaging modalities used for anatomic evaluation of pathologic processes affecting the brain. By contrast, radionuclide-based methods, including planar imaging, single-photon emission computed tomography (SPECT), and positron emission tomography (PET), are the most widely used methods for evaluating brain function. SPECT and PET have been evolving for a longer time than CT and MRI and have made significant contributions to understanding brain function. The pioneering work on cerebral flow early in the last century laid the foundation of measurement with radioactive gases. This was initially performed with scintillation counters, which gave way to single, then multiple scintillation and multiprobe detectors. The invention of rectilinear scanners, MARK series, Anger cameras, and SPECT imaging further advanced nuclear medicine's role in brain imaging. Measurement of regional cerebral blood flow by SPECT provides pathophysiologic information that directs patient management in a variety of central nervous disorders (CNS), with the greatest clinical impact found in cerebrovascular disease and seizure disorder. In the former, SPECT not only provides means of early detection and localization of acute strokes but can also direct thrombolysis and determine prognosis in the postcerebrovascular accident period. With respect to the latter, ictal SPECT can localize seizure foci so that patients with refractory disease can potentially undergo surgical resection of the affected area. In contrast to brain SPECT, brain PET images reflect regional cerebral metabolism. Because of neurovascular coupling, findings on SPECT and PET images are often comparable. PET, however, still has improved spatial resolution and is therefore more sensitive than SPECT, particularly in the evaluation of dementias. Brain PET instrumentation has greatly evolved from its infancy, when it was used in regional localization, to currently providing excellent resolution with imaging characteristics that can greatly impact clinical management. In addition, although ictal SPECT remains more sensitive than interictal PET for detection of seizure foci, the stringent conditions required for SPECT can be difficult to achieve, making interictal PET a very reasonable alternative. The clinical utility of PET and SPECT in neuropsychiatric and addictive disorders has not yet been defined, though a plethora of data exits. This arena of CNS disease has been the impetus for development of neurotransmitter-receptor-specific radioligands, which have already led to better understanding of dopaminergic, GABAergic, and serotonergic pathways. Another functional brain imaging technique that has gained broad acceptance since its invention in the early 1990 s, is functional MRI, which indirectly measures CNS neuronal activity by evaluating oxygenation levels of cerebral vessels. Despite other recent related developments, such as MR spectroscopy, arterial spin labeling, and diffusion tensor imaging, nuclear medicine-based techniques remain clinically relevant and robust modalities, especially with the ever-expanding armamentarium of radiotracers and radioligands in conjunction with industry-driven improvements in image-analysis hardware and software.

Risk factors for squamous intraepithelial lesions (SIL) of the cervix among women residing at the US-Mexico border.

It is now well established that cervical cancer is caused by oncogenic human papillomavirus (HPV) infections that commonly infect women worldwide. What remains to be understood are the factors that contribute to cervical cancer in the presence of HPV infection. We conducted a case-control analysis of women recruited at the US-Mexico border to simultaneously evaluate factors associated with 3 cytologic outcomes: atypical squamous cells of undetermined significance or atypical glandular cells of undetermined significance (ASCUS/AGUS), low grade squamous intraepithelial lesions (LSIL) and high grade squamous intraepithelial lesions (HSIL). A cross-sectional binational study of 2059 women ages 15-79 years was conducted between 1997 and 1998. A significant difference in the distribution of cytologic categories by country was observed (3.0% vs. 0.7% HSIL among Mexican vs. US women, respectively). The only factors independently associated with all 3 cytologic outcomes were HPV infection and viral load. A linear increase in risk with increasing viral load was observed for each of the 3 outcome variables, with the strength of this association increasing with cytology abnormality. In addition to HPV infection, parity and Mexico as a country of residence appear to be associated with LSIL and HSIL, respectively. Factors associated with cytologic outcomes in analyses limited to women with HPV infection were similar to results obtained in models where HPV infection was included as a covariate. Future work is needed to evaluate the predictive value of HPV viral load utilizing more specific and quantitative measures.