Can the Risk of Lymph Node Metastases Be Gauged in Endoscopically Resected Submucosal Esophageal Adenocarcinomas? A Multi-Center Study.

Endoscopic resection (ER) allows for local therapy of superficial esophageal cancers. Factors reported to be associated with an increased risk of lymph node metastases in patients with adenocarcinoma are poor differentiation, lymphovascular invasion (LVI), and submucosal invasion >500 µ. The aim of this study was to determine whether depth of invasion and tumor characteristics in an ER specimen can be used to gauge the risk of lymph node metastases in patients with superficial esophageal adenocarcinoma. Patients from seven US centers that had ER of an adenocarcinoma followed by an esophagectomy were identified. The ER pathology slides were rereviewed by three experienced GI pathologists for depth of invasion, presence of LVI, and tumor differentiation. The findings from the ER specimen were correlated with the presence and number of lymph node metastases in the final esophagectomy specimen. There were 19 T1a and 23 T1b tumors. A median of 24 nodes were resected per patient. None of the T1a tumors had involved lymph nodes despite the presence of LVI in 5% and poor differentiation in 21% of patients. In contrast, 26% of T1b tumors had involved nodes. None of the four patients with submucosal invasion ≤500 µ, no LVI, and no poor differentiation had involved nodes. However, with an increasing number of risk factors, the likelihood of involved lymph nodes increased, reaching 50% when all three factors were present. Endoscopic therapy appears appropriate for intramucosal tumors and may be an option for low-risk T1b tumors. Esophagectomy is preferred for patients with submucosal invasion and one or more risk factors.

Inter-Observer Variability in the Interpretation of Endoscopic Mucosal Resection Specimens of Esophageal Adenocarcinoma: Interpretation of ER specimens.

INTRODUCTION: Endoscopic resection (ER) has revolutionized the staging and therapy of superficial esophageal adenocarcinoma. Pathologic evaluation allows an assessment of the risk of lymph node metastases based on tumor characteristics. The aim of this study was to assess the inter-observer variability in pathologic assessment of ER specimens of esophageal adenocarcinoma. METHODS: We performed a retrospective study on ER specimens of superficial esophageal adenocarcinoma from four US institutions. Original endoscopic resection slides were re-reviewed by two blinded, experienced (study) gastrointestinal pathologists for the depth of tumor invasion, tumor grade, and the presence of lymphovascular invasion (LVI). Discordance was considered present only when both study pathologists disagreed with the original report. RESULTS: There were 25 ER specimens reviewed for this study, and discordance occurred in 12 of the 25 specimens (48%) for the depth of tumor invasion. In most cases (83%), the discordance was related to overstaging a true T1a lesion. We found that only 38% of true T1a lesions were correctly staged for depth of invasion. Less commonly discordance was secondary to understaging a true T1b lesion. There was concordance between the two study pathologists in 22/25 cases (88%) on the depth of invasion. Discordance was present for tumor grade in 8/18 cases (44%) and for LVI in 4/16 cases (25%). Concordance between the study pathologists was 80% for tumor grade and 88% for LVI. CONCLUSIONS: There was an alarmingly high rate of discordance (48%) between the study pathologists and the original pathology assessment for the depth of tumor invasion in ER specimens. This was particularly common for lesions called T1b on the original pathology report. Since critical decisions are made regarding esophageal preservation or esophagectomy on the basis of the pathologic interpretations of ER specimens, it behooves surgeons to understand the inter-observer variability. Review of ER specimens by an experienced GI pathologist is recommended to ensure that patients receive the appropriate treatment for superficial esophageal adenocarcinoma.

Whole slide imaging for human epidermal growth factor receptor 2 immunohistochemistry interpretation: Accuracy, Precision, and reproducibility studies for digital manual and paired glass slide manual interpretation.

BACKGROUND: The use of digital whole slide imaging for human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) could create improvements in workflow and performance, allowing for central archiving of specimens, distributed and remote interpretation, and the potential for additional computerized automation. PROCEDURES: The accuracy, precision, and reproducibility of manual digital interpretation for HER2 IHC were determined by comparison to manual glass slide interpretation. Inter- and intra-pathologist reproducibility and precision between the glass slide and digital interpretations of HER2 IHC were determined in 5 studies using DAKO HercepTest-stained breast cancer slides with the Philips Digital Pathology System. In 2 inter-method studies, 3 pathologists interpreted glass and digital slides in sequence or in random order with a minimum of 7 days as a washout period. These studies also measured inter-observer reproducibility and precision. Another two studies measured intra-pathologist reproducibility on cases read 10 times by glass and digital methods. One additional study evaluated the effects of adding IHC control slides with each run, using 1 pathologist interpreting glass and digital slides randomized from the sets above along with appropriate controls for each slide in the set. RESULTS: The overall results show that there is no statistical difference between the variance of performance when comparing glass and digital HER2 interpretations; and there were no effects noted when control tissues were evaluated in conjunction with the test slides. CONCLUSIONS: The results show that there is an equivalence of result when interpreting HER2 IHC slides in breast cancer by either glass slides or digital images. Digital interpretation can therefore be safely and effectively used for this purpose.

Human esophageal myofibroblasts secrete proinflammatory cytokines in response to acid and Toll-like receptor 4 ligands.

The pathophysiology of esophageal injury, repair, and inflammation in gastroesophageal reflux-disease (GERD) is complex. Whereas most studies have focused on the epithelial response to GERD injury, we are interested in the stromal response. We hypothesized that subepithelial esophageal myofibroblasts in GERD secrete proinflammatory cytokines in response to injurious agents encountered via epithelial barrier breaches or through dilated epithelial intercellular spaces. We determined the percentage of myofibroblasts [-smooth muscle actin (-SMA)+vimentin+CD31-] in the subepithelial GERD and normal esophageal stroma by immunomorphologic analysis. We performed -SMA coimmunostaining with IL-6 and p65. We established and characterized primary cultures of -SMA+vimentin+CD31-CD45- human esophageal myofibroblasts (HuEso MFs). We modeled GERD by treatment with pH 4.5-acidified media and Toll-like receptor 4 (TLR4) ligands, LPS and high-mobility group box 1 protein (HMGB1), and determined myofibroblast cytokine secretion in response to GERD injury. We demonstrate that spindle-shaped cell myofibroblasts are located near the basement membrane of stratified squamous epithelium in normal esophagus. We identify an increase in subepithelial myofibroblasts and activation of proinflammatory pathways in patients with GERD. Primary cultures of stromal cells obtained from normal esophagus retain myofibroblast morphology and express the acid receptor transient receptor potential channel vanilloid subfamily 1 (TRPV1) and TLR4. HuEso MFs stimulated with acid and TLR4 agonists LPS and HMGB1 increase IL-6 and IL-8 secretion via TRPV1 and NF-B activation. Our work implicates a role for human subepithelial stromal cells in the pathogenesis of GERD-related esophageal injury. Findings of this study can be extended to the investigation of epithelial-stromal interactions in inflammatory esophageal mucosal disorders.

Effects of luteinizing hormone receptor signaling in prostate cancer cells.

BACKGROUND: The importance of androgen signaling in prostate cancer (PC) is well described and prostate cancer cells retain the ability to directly synthesize androgens. Luteinizing hormone (LH) can induce expression of steroidogenic enzymes and trigger androgen production, but the regulation of this process is not well-described. Here, we explored the impact of silencing LH receptor (LHR) silencing on androgen synthesis and on several relevant signaling pathways in PC. METHODS: LHR mRNA and protein expression was evaluated in LNCaP PC cells treated with LHR-siRNA. MTS assay was used to measure the effect of LHR-siRNA on proliferation in LNCaP and 22RV1 PC cells. Treated LNCaP and LAPC-3 cells were also assayed for differences in androgen synthesis and expression of steroidogenic enzymes, PSA, AR, and critical signaling molecules including PKA, ERK1/2, PI3K, AKT2, and HER2. RESULTS: We confirmed that functional LHR is expressed in both androgen-sensitive and castrate-resistant PC specimens. Treatment with LHR-siRNA effectively silenced LHR gene and protein expression and prevented LH-mediated proliferation and androgen synthesis in prostate cancer cells. LHR silencing also downregulated expression of AR, PSA, PKA, ERK1/2, PI3K, AKT2, and HER2. CONCLUSION: Collectively, these data demonstrate that silencing LHR expression suppresses androgen synthesis and signaling and the LH-LHR pathway may represent a viable therapeutic strategy in PC.