Immune Marker Profiling and Programmed Death Ligand 1 Expression Across NSCLC Mutations.

INTRODUCTION: Programmed death 1/programmed death ligand 1 (PD-L1) axis inhibitors have been proven effective, especially in patients with tumors expressing PD-L1. Their clinical efficacy in patients with EGFR-activating mutations is still unclear, whereas KRAS mutations seem to be associated with good response. METHODS: We used multiplexed quantitative immunofluorescence to investigate PD-L1 expression and to characterize tumor infiltrating lymphocyte (TIL) populations and their activation status in more than 150 NSCLC patients with known mutation status. RESULTS: PD-L1 expression was significantly lower in EGFR-mutant compared to KRAS-mutant, and EGFR/KRAS wild-type (WT) tumors. KRAS mutant tumors were more inflamed with higher CD4+, CD8+ and CD20+ TILs. Subgroup analysis by TIL activation status revealed that EGFR mutants had a high frequency of inactive TILs even though lymphocytes were present in the tumor microenvironment. In contrast, in KRAS mutants, when TILs were present they were almost always active. Additionally, we found differences between EGFR mutation sites in CD8+ expression and the TIL activation profile. Finally, activated EGFR correlated with increased PD-L1 expression in EGFR mutants but not in EGFR WT, whereas TIL activation was associated with higher PD-L1 only in EGFR/KRAS WT. CONCLUSIONS: Our findings show the unique immune profile of EGFR-mutant tumors. The high frequency of inactive TILs could explain the low immunotherapy response rates in these patients, whereas PD-L1 as a predictive biomarker may reflect the constitutive oncogenic signaling rather than immune signaling, which would be associated with high PD-L1 levels and TILs activation.

Tumor-Infiltrating Lymphocytes and PD-L1 Expression in Pre- and Posttreatment Breast Cancers in the SWOG S0800 Phase II Neoadjuvant Chemotherapy Trial.

Our aim was to examine the association of pretreatment tumor-infiltrating lymphocyte (TIL) count and PD-L1 levels with pathologic complete response (pCR) and assess immune marker changes following treatment in tumor specimens from the S0800 clinical trial, which randomized patients to bevacizumab + nab-paclitaxel, followed by doxorubicin/cyclophosphamide (AC) versus two control arms without bevacizumab (varying sequence of AC and nab-paclitaxel). TILs were assessed in 124 pre- and 62 posttreatment tissues (including 59 pairs). PD-L1 was assessed in 120 pre- and 43 posttreatment tissues (including 39 pairs) using the 22C3 antibody. Baseline and treatment-induced immune changes were correlated with pCR and survival using estrogen receptor (ER) and treatment-adjusted logistic and Cox regressions, respectively. At baseline, the mean TIL count was 17.4% (17% had zero TILs, 9% had ≥50% TILs). Posttreatment, mean TIL count decreased to 11% (5% had no TILs, 2% had >50% TILs). In paired samples, the mean TIL change was 15% decrease. Baseline PD-L1 was detected in 43% of cases (n = 5 in tumor cells, n = 29 stroma, n = 18 tumor + stroma). Posttreatment, PD-L1 expression was not significantly lower (33%). Higher baseline TIL count and PD-L1 positivity rate were associated with higher pCR rate even after adjustment for treatment and ER status (P = 0.018). There was no association between TIL counts, PD-L1 expression, and survival due to few events. In conclusion, TIL counts, but not PD-L1 expression, decreased significantly after treatment. Continued PD-L1 expression in some residual cancers raises the possibility that adjuvant immune checkpoint inhibitor therapy could improve survival in this patient population. Mol Cancer Ther; 17(6); 1324-31. ©2018 AACR.

High concordance of a closed-system, RT-qPCR breast cancer assay for HER2 mRNA, compared to clinically determined immunohistochemistry, fluorescence in situ hybridization, and quantitative immunofluorescence.

Historically, mRNA measurements have been tested on several commercially available platforms, but none have gained broad acceptance for assessment of HER2. An mRNA measurement, as a continuous value, has the potential for use in adjudication of the equivocal category. Here we use a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay in a closed, single-use cartridge, automated system. Multiple cores (1 mm in diameter) were retrospectively collected from 80 formalin-fixed paraffin-embedded (FFPE) tissue blocks with invasive breast cancer seen by Yale Pathology Labs between 1998 and 2011. Tissue cores were processed with a FFPE lysis kit to create lysates that were tested with the automated RT-qPCR assay. Results for IHC and FISH were extracted from the pathology reports and quantitative immunofluorescence (QIF) for each case was measured as previously described. Quality control testing showed that the GX platform RT-qPCR shows no case to case cross contamination on material from routine histology practices. Concordance between RT-qPCR and IHC/FISH was 91.25% (sensitivity=0.87; specificity=0.94; PPV=0.89; NPV=0.92) using a pre-defined delta Ct cut-off (dCt≥-1) for HER2. Concordance (OPA) between RT-qPCR and QIF was 94% (sensitivity=0.90; specificity=0.96; PPV=0.93; NPV=0.94) using dCt≥-1 and a previously defined cut-point for positivity by QIF. In conclusion, the closed system RT-qPCR assay shows >90% concordance with the ASCO/CAP HER2 IHC/FISH scoring. Additionally, the RT-qPCR assay is highly concordant (94%) with the continuous variable HER2 QIF assay, and may better reflect the true continuum of HER2 receptor status in invasive breast cancer. These initial results suggest that fast, closed system molecular assays may have future value for the adjudication of the ASCO/CAP HER2 equivocal category or possibly routine usage in time constrained or low resource settings.

Effect of neoadjuvant chemotherapy on tumor-infiltrating lymphocytes and PD-L1 expression in breast cancer and its clinical significance.

BACKGROUND: The effects of neoadjuvant chemotherapy on immune markers remain largely unknown. The specific aim of this study was to assess stromal tumor-infiltrating lymphocytes (TILs) and programmed death ligand 1 (PD-L1) protein expression in a cohort of breast cancer patients treated with neoadjuvant chemotherapy. METHODS: Using quantitative immunofluorescence, we investigated stromal TILs and PD-L1 protein expression in pre-treatment and residual breast cancer tissue from a Yale Cancer Center patient cohort of 58 patients diagnosed with breast cancer from 2003 to 2009 and treated with neoadjuvant chemotherapy. We compared the TIL count and PD-L1 status in paired pre-treatment and residual cancer tissues and correlated changes and baseline levels with survival. RESULTS: Of the 58 patients, 46 (79.3%) had hormone-positive and 34 (58.6%) had node-positive breast cancer. Eighty-six percent of residual cancer tissues had TIL infiltration and 17% had PD-L1 expression. There was a trend for higher TIL counts in postchemotherapy compared to prechemotherapy samples (p = 0.09). Increase in TIL count was associated with longer 5-year recurrence-free survival (p = 0.02, HR = 3.9, 95% CI = 1.179-15.39). PD-L1 expression (both stromal and tumor cells) was significantly lower in post-treatment samples (p = 0.001). Change in PD-L1 expression after therapy or TILs and PD-L1 expression in the posttreatment samples did not correlate with survival. CONCLUSIONS: Increase in stromal TILs in residual cancer compared to pretreatment tissue is associated with improved recurrence-free survival. Despite a trend for increasing TIL counts, PD-L1 expression decreased in residual disease compared to pretreatment samples.

Cleaning and Sterilization of Used Cardiac Implantable Electronic Devices With Process Validation: The Next Hurdle in Device Recycling.

OBJECTIVES: This study sought to develop a validated, reproducible sterilization protocol, which could be used in the reprocessing of cardiac implantable electronic devices (CIEDs). BACKGROUND: Access to cardiac CIED therapy in high-income and in low- and middle-income countries varies greatly. CIED reuse may reduce this disparity. METHODS: A cleaning and sterilization protocol was developed that includes washing CIEDs in an enzymatic detergent, screw cap and set screw replacement, brushing, inspection, and sterilization in ethylene oxide. Validation testing was performed to assure compliance with accepted standards. RESULTS: With cleaning, the total mean bioburden for each of 3 batches of 10 randomly chosen devices was reduced from 754 to 10.1 colony-forming units. After sterilization with ethylene oxide, with 3 half-cycle and 3 full-cycle processes, none of the 90 biological indicator testers exhibited growth after 7 days. Through cleaning and sterilization, protein and hemoglobin concentrations were reduced from 99.2 to 1.42 µg/cm2 and from 21.4 to 1.03 µg/cm2, respectively. Mean total organic carbon residual was 1.44 parts per million (range 0.36 to 2.9 parts per million). Endotoxin concentration was not detectable at the threshold of <0.03 endotoxin units/ml or <3.0 endotoxin units/device. Cytotoxicity and intracutaneous reactivity tests met the standards set by the Association for Advancement of Medical Instrumentation and the International Organization for Standardization. CONCLUSIONS: CIEDs can be cleaned and sterilized according to a standardized protocol achieving a 12-log reduction of inoculated product, resulting in sterility assurance level of 10-6.

Quantitative and pathologist-read comparison of the heterogeneity of programmed death-ligand 1 (PD-L1) expression in non-small cell lung cancer.

PD-L1 is expressed in a percentage of lung cancer patients and those patients show increased likelihood of response to PD-1 axis therapies. However, the methods and assays for the assessment of PD-L1 using immunohistochemistry are variable and PD-L1 expression appears to be highly heterogeneous. Here, we examine assay heterogeneity parameters toward the goal of determining variability of sampling and the variability due to pathologist-based reading of the immunohistochemistry slide. SP142, a rabbit monoclonal antibody, was used to detect PD-L1 by both chromogenic immunohistochemistry and quantitative immunofluorescence using a laboratory-derived test. Five pathologists scored the percentage of PD-L1 positivity in tumor- and stromal-immune cells of 35 resected non-small cell lung cancer cases, each represented on three separate blocks. An intraclass correlation coefficient of 94% agreement was seen among the pathologists for the assessment of PD-L1 in tumor cells, but only 27% agreement was seen in stromal/immune cell PD-L1 expression. The block-to-block reproducibility of each pathologist's score was 94% for tumor cells and 75% among stromal/immune cells. Lin's concordance correlation coefficient between pathologists' readings and the mean immunofluorescence score among blocks was 94% in tumor and 68% in stroma. Pathologists were highly concordant for PD-L1 tumor scoring, but not for stromal/immune cell scoring. Pathologist scores and immunofluorescence scores were concordant for tumor tissue, but not for stromal/immune cells. PD-L1 expression was similar among all the three blocks from each tumor, indicating that staining of one block is enough to represent the entire tumor and that the spatial distribution of heterogeneity of expression of PD-L1 is within the area represented in a single block. Future studies are needed to determine the minimum representative tumor area for PD-L1 assessment for response to therapy.

Feasibility of postmortem device acquisition for potential reuse in underserved nations.

OBJECTIVES: The purpose of the present study was to examine the feasibility and efficacy of a program to acquire devices with adequate battery life from crematories and funeral homes for potential reutilization in underserved nations. BACKGROUND: There exists a great health-care disparity between the industrialized world and underserved nations--specifically in the frequency of pacemaker implantation. METHODS: Flyers were mailed to all 1057 members of the Michigan Funeral Directors Association providing information to download a consent-for-explant form and request a postage-paid envelope from www.myheartyourheart.org in order to send explanted devices. Donated devices from funeral homes and crematories nationwide were also collected from World Medical Relief. Adequate battery life was defined as ≥75% or ≥4 years of estimated longevity. RESULTS: A total of 3176 devices (65% pacemakers, 21% implantable cardioverter-defibrillators [ICDs], 12% biventricular ICDs, and 3% biventricular pacemakers) were donated to the reutilization program. Five hundred fifty devices (21%; 95% confidence interval [CI] 19.4-22.6%) were found to have an acceptable battery life for reutilization. Among these devices, 313 were pacemakers (17.9%; 95% CI 16.1-19.8%), 118 were ICDs (17.9%; 95% CI 15.1-21.1%), 112 were biventricular ICDs (30.3%; 95% CI 25.6-35.2%), and 7 were biventricular pacemakers (17.3%; 95% CI 16.0-18.7%). CONCLUSIONS: Approximately 21% of donated devices and 30% of donated biventricular ICDs possess an adequate battery life for potential reuse. Device donations from funeral homes and crematories appear to be a potential resource for device reutilization for those in need in underserved nations.

Prepubertal distal longitudinal vaginal folds.

OBJECTIVE: The purpose of this paper is to further describe prepubertal distal longitudinal vaginal folds and its natural history. DESIGN: Biopsy of the folds and follow-up through puberty. RESULTS: Histology of the folds shows normal vaginal mucosa over loose fibrous connective tissue without a firm fibrous core. The folds disappear in puberty. CONCLUSIONS: Prepubertal distal longitudinal folds are common, and disappear probably by spreading out during puberty with the physiologic estrogenic widening and lengthening of the vagina. This can occur because the folds do not have a dense fibrous core. The folds may be confused with the vaginal rhabdomyosarcoma or sexual molestation if the fold reaches the hymen, and forms a "bump". The folds are benign.