Utilizing multimodal mass spectrometry imaging for profiling immune cell composition and N-glycosylation across colorectal carcinoma disease progression

Colorectal cancer (CRC) stands as a leading cause of death worldwide, often arising from specific genetic mutations, progressing from pre-cancerous adenomas to adenocarcinomas. Early detection through regular screening can result in a 90% 5-year survival rate for patients. However, unfortunately, only a fraction of CRC cases are identified at pre-invasive stages, allowing progression to occur silently over 10-15 years. The intricate interplay between the immune system and tumor cells within the tumor microenvironment plays a pivotal role in the progression of CRC. Immune cell clusters can either inhibit or facilitate tumor initiation, growth, and metastasis. To gain a better understanding of this relationship, we conducted N-glycomic profiling using matrix-assisted laser desorption-ionization mass spectrometry imaging (MALDI-MSI). We detected nearly 100 N-glycan species across all samples, revealing a shift in N-glycome profiles from normal to cancerous tissues, marked by a decrease in high mannose N-glycans. Further analysis of precancerous to invasive carcinomas showed an increase in pauci-mannose biantennary, and tetraantennary N-glycans with disease progression. Moreover, a distinct stratification in the N-glycome profile was observed between non-mucinous and mucinous CRC tissues, driven by pauci-mannose, high mannose, and bisecting N-glycans. Notably, we identified immune clusters of CD20+ B cells and CD3/CD44+ T cells distinctive and predictive with signature profiles of bisecting and branched N-glycans. These spatial N-glycan profiles offer potential biomarkers and therapeutic targets throughout the progression of CRC.

Abstract PO-196: Upregulation of bacterial and fungal pathogen sensing genes in preinvasive colorectal lesions in African Americans compared to Caucasian Americans

Background: Colorectal cancer (CRC) incidence and mortality are higher for African Americans (AAs) than Caucasian Americans (CAs). Variation in tumor immune responses by race appears to be important for prognosis. However, few studies have compared immune gene expression in preinvasive lesions where prevention may be possible. Methods: The immune gene expression of 95 cases of colorectal adenomas (AA 47, CA 48) excised via sigmoidoscopy or colonoscopy with polypectomy between October 2012 and May 2016 was assessed using the NanoString nCounter platform using the immunology v2 panel (n=579 genes). Data were analyzed using a NanoStringDiff R package, implementing negative binomial regression models of gene expression as the dependent variable and race group (AA vs. CA) as the primary predictor variable. Models were adjusted for age, sex, location within the colon, histology, and degree of dysplasia. Results: In AAs vs. CAs, 24 immune genes were up-regulated, while 11 genes were down-regulated (for each gene, p<0.01). Compared to CAs, genes overexpressed in AAs suggest more robust antibacterial and antifungal responses (e.g., IL17F, IL21, AIRE, IL1A, GATA3, MARCO, FCGR1A). Enhanced expression of terminal components of the complement pathway C8B and C9 further support an increased effector response in AAs. Additionally, genes related to wound healing (e.g., GP1BB, XCL1) were overexpressed in AAs. Genes associated with stimulation of cytotoxic responses (NCR1, HLADRB1), complement activation through lectin-related pathways (ITLN2, MBL2), and recruitment and function of innate immune cells (IL8 and IL6) had lower expression in AAs vs. CAs. Conclusion: Our results suggest that preinvasive neoplasms in AAs vs. CAs display a gene expression that is suggestive of heightened sensing of bacterial and fungal commensals, which may potentially inflame local tissues and support tumor progression. Understanding the molecular differences in early tumorigenesis between AAs vs. CAs may help inform prevention interventions to address racial disparities.

Citation Format: Silvia Guglietta, Lauren R. Fanning, Alexandria G. Cousart, Kent E. Armeson, Zequn Sun, David N. Lewin, J Grant Brazeal, Dongjun Chung, Alexander V. Alekseyenko, Kristin Wallace. Upregulation of bacterial and fungal pathogen sensing genes in preinvasive colorectal lesions in African Americans compared to Caucasian Americans [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-196.

Immune Responses Vary in Preinvasive Colorectal Lesions by Tumor Location and Histology

Immune responses vary in colorectal cancers, which strongly influence prognosis. However, little is known about the variance in immune response within preinvasive lesions. The study aims to investigate how the immune contexture differs by clinicopathologic features (location, histology, dysplasia) associated with progression and recurrence in early carcinogenesis. We performed a cross-sectional study using preinvasive lesions from the surgical pathology laboratory at the Medical University of South Carolina. We stained the tissues with immunofluorescence antibodies, then scanned and analyzed expression using automated image analysis software. We stained CD117 as a marker of mast cells, CD4/RORC to indicate Th17 cells, MICA/B as a marker of NK-cell ligands, and also used antibodies directed against cytokines IL6, IL17A, and IFNγ. We used negative binomial regression analysis to compare analyte density counts by location, histology, degree of dysplasia adjusted for age, sex, race, and batch. All immune markers studied (except IL17a) had significantly higher density counts in the proximal colon than distal colon and rectum. Increases in villous histology were associated with significant decreases in immune responses for IL6, IL17a, NK ligand, and mast cells. No differences were observed in lesions with low- and high-grade dysplasia, except in mast cells. The lesions of the proximal colon were rich in immune infiltrate, paralleling the responses observed in normal mucosa and invasive disease. The diminishing immune response with increasing villous histology suggests an immunologically suppressive tumor environment. Our findings highlight the heterogeneity of the immune responses in preinvasive lesions, which may have implications for prevention strategies. PREVENTION RELEVANCE: Our study is focused on immune infiltrate expression in preinvasive colorectal lesions; our results suggest important differences by clinicopathologic features that have implications for immune prevention research.

The Utility of Liver Biopsy in the Evaluation of Liver Disease and Abnormal Liver Function Tests

OBJECTIVES

We aimed to assess the value of liver biopsy in the evaluation of abnormal liver tests.

METHODS

We analyzed consecutive liver biopsy specimens performed for evaluation of unexplained abnormal liver tests from 2014 to 2018. Diagnoses were categorized histologically and clinically. We determined whether histologic examination led to a specific diagnosis and whether prebiopsy laboratory variables predicted the underlying etiology.

RESULTS

Among the 383 liver biopsy specimens included, chronic hepatitis was the most common histologic (25%) and clinical (17%) diagnosis. Liver biopsy led to a clinical diagnosis in 87% of patients. The most likely clinical diagnoses were autoimmune hepatitis, nonalcoholic fatty liver disease, and drug-induced liver injury (38, 33, and 32 patients, respectively). Using sensitivity, specificity, and positive and negative predictive values, we found that liver tests were not predictive of a specific diagnosis. In patients with no history of liver disease or clinical features of portal hypertension, biopsy specimens revealed histologic cirrhosis in 5% of patients.

CONCLUSIONS

Histopathologic diagnoses were made in 85% of patients undergoing liver biopsy for investigation of unexplained liver tests, leading to a clinical diagnosis in 87% of patients. However, neither liver tests themselves nor their patterns were useful in predicting histologic or clinical diagnoses.

Preinvasive Colorectal Lesions of African Americans Display an Immunosuppressive Signature Compared to Caucasian Americans

Background

African Americans (AAs) have higher colorectal cancer (CRC) incidence and mortality rate than Caucasian Americans (CAs). Recent studies suggest that immune responses within CRCs contribute to the disparities. If racially distinct immune signatures are present in the early phases of carcinogenesis, they could be used to develop interventions to prevent or slow disease.

Methods

We selected a convenience sample of 95 patients (48 CAs, 47 AAs) with preinvasive colorectal adenomas from the surgical pathology laboratory at the Medical University of South Carolina. Using immunofluorescent-conjugated antibodies on tissue slides from the lesions, we quantified specific immune cell populations: mast cells (CD117⁺), Th17 cells (CD4⁺RORC⁺), and NK cell ligand (MICA/B) and inflammatory cytokines, including IL-6, IL-17A, and IFN-γ. We compared the mean density counts (MDCs) and density rate ratios (RR) and 95% CI of immune markers between AAs to CAs using negative binomial regression analysis. We adjusted our models for age, sex, clinicopathologic characteristics (histology, location, dysplasia), and batch.

Results

We observed no racial differences in age or sex at the baseline endoscopic exam. AAs compared to CAs had a higher prevalence of proximal adenomas (66% vs. 40%) and a lower prevalence of rectal adenomas (11% vs. 23%) (p =0.04) but no other differences in pathologic characteristics. In age, sex, and batch adjusted models, AAs vs. CAs had lower RRs for cells labeled with IFNγ (RR 0.50 (95% CI 0.32-0.81); p=0.004) and NK cell ligand (RR 0.67 (0.43-1.04); p=0.07). In models adjusted for age, sex, and clinicopathologic variables, AAs had reduced RRs relative to CAs for CD4 (p=0.02), NK cell ligands (p=0.01), Th17 (p=0.005), mast cells (p=0.04) and IFN-γ (p< 0.0001).

Conclusions

Overall, the lower RRs in AAs vs. CAs suggests reduced effector response capacity and an immunosuppressive (‘cold’) tumor environment. Our results also highlight the importance of colonic location of adenoma in influencing these differences; the reduced immune responses in AAs relative to CAs may indicate impaired immune surveillance in early carcinogenesis. Future studies are needed to understand the role of risk factors (such as obesity) in influencing differences in immune responses by race.

Nodular Regenerative Hyperplasia of the Liver in Rheumatic Disease: Cases and Review of the Literature

Nodular regenerative hyperplasia (NRH) is a rare disease that is characterized by benign transformation of the hepatic parenchyma into small nodules with little to no fibrosis. Nodular regenerative hyperplasia is a cause of noncirrhotic portal hypertension. Symptoms can range from asymptomatic disease to more serious complications of portal hypertension such as esophageal varices and ascites. Nodular regenerative hyperplasia has been described in association with a variety of different rheumatologic, hematologic, and oncologic diseases, as well as in immune deficiency states and with exposures to certain toxins. Diagnosis is made by histology, and the treatment involves addressing the underlying disease. The first description of this rare disease was actually described in a patient with rheumatoid arthritis, neutropenia, and splenomegaly (Felty's Syndrome). We describe 2 cases of NRH associated with underlying rheumatic disorders, in one of which NRH was actually the presenting feature of the patient's underlying autoimmune condition. Subsequently, we provide a brief review of the literature of NRH in autoimmune disease with respect to epidemiology, cause, clinical manifestations, diagnosis, and treatment.

Imaging Mass Spectrometry and Lectin Analysis of N-Linked Glycans in Carbohydrate Antigen-Defined Pancreatic Cancer Tissues

The early detection of pancreatic ductal adenocarcinoma (PDAC) is a complex clinical obstacle yet is key to improving the overall likelihood of patient survival. Current and prospective carbohydrate biomarkers carbohydrate antigen 19-9 (CA19-9) and sialylated tumor-related antigen (sTRA) are sufficient for surveilling disease progression yet are not approved for delineating PDAC from other abdominal cancers and noncancerous pancreatic pathologies. To further understand these glycan epitopes, an imaging mass spectrometry (IMS) approach was used to assess the N-glycome of the human pancreas and pancreatic cancer in a cohort of patients with PDAC represented by tissue microarrays and whole-tissue sections. Orthogonally, these same tissues were characterized by multiround immunofluorescence that defined expression of CA19-9 and sTRA as well as other lectins toward carbohydrate epitopes with the potential to improve PDAC diagnosis. These analyses revealed distinct differences not only in N-glycan spatial localization across both healthy and diseased tissues but importantly between different biomarker-categorized tissue samples. Unique sulfated biantennary N-glycans were detected specifically in normal pancreatic islets. N-glycans from CA19-9-expressing tissues tended to be biantennary, triantennary, and tetra-antennary structures with both core and terminal fucose residues and bisecting GlcNAc. These N-glycans were detected in less abundance in sTRA-expressing tumor tissues, which favored triantennary and tetra-antennary structures with polylactosamine extensions. Increased sialylation of N-glycans was detected in all tumor tissues. A candidate new biomarker derived from IMS was further explored by fluorescence staining with selected lectins on the same tissues. The lectins confirmed the expression of the epitopes in cancer cells and revealed different tumor-associated staining patterns between glycans with bisecting GlcNAc and those with terminal GlcNAc. Thus, the combination of lectin-immunohistochemistry and lectin-IMS techniques produces more complete information for tumor classification than the individual analyses alone. These findings potentiate the development of early assessment technologies to rapidly and specifically identify PDAC in the clinic that may directly impact patient outcomes.

Racial disparity in survival of patients diagnosed with early-onset colorectal cancer

Background: Survival is reduced in African–Americans (AAs) diagnosed with colorectal cancer (CRC), especially in those <50 years old, when compared with Caucasian Americans (CAs). Yet, the role of clinicopathologic features of CRCs on racial differences in survival needs further study. Materials & methods: Over 1000 individuals (CA 709, AA 320) diagnosed with CRC were studied for survival via the Cox proportional hazards regression analysis based on race and risk of death in two age groups (<50 or 50+). Results: Risk of death for younger AAs (<50) was elevated compared with younger CAs (hazard ratio [HR] 1.98 [1.26–3.09]). Yet no racial differences in survival was observed in older cohort (50+ years), HR 1.07 (0.88–1.31); p for interaction = 0.01. In younger AAs versus CAs only, colonic location attenuated the risk of death. Conclusion: The tumor location and histology influence the poorer survival observed in younger AAs suggesting these may also influence treatment responses.

Synchronous Upper Intestinal Neurofibromas and Duodenal Periampullary Well-Differentiated Neuroendocrine Tumor Associated With Neurofibromatosis 1

Neurofibromatosis type I (NF1) is an autosomal dominant genetic disorder associated with characteristic skin findings, as well as a fourfold increase in risk of malignancy. NF1 patient malignancies commonly include the central and peripheral nervous system, but these patients are also at high risk of developing gastrointestinal (GI) tumors. While most often these GI tumors are benign upper GI neurofibromas; clinicians should have a high suspicion for malignant tumors, degeneration into a malignant peripheral nerve sheath tumor or less common associated malignancies such as well-differentiated neuroendocrine tumor (formerly carcinoid tumor), when patients present with multiple GI tumors. Our patient underwent a Whipple for symptomatic neurofibromas associated with NF1 and was unexpectedly discovered to have a metastatic duodenal well-differentiated neuroendocrine tumor. The patient is a 66-year-old man with NF1 who presented with hematemesis and was found to have large gastric neurofibromas and an ampullary neurofibroma based on endoscopy and radiological imaging. Another ostensive neurofibroma was noted distally. A pancreatoduodenectomy was performed. Pathological examination identified the neurofibromas but the tumor measuring 1.4cm and arising from the minor duodenal papilla was, in fact, a synchronous well-differentiated neuroendocrine tumor metastatic to regional lymph nodes, consistent with pT2 pN1, Stage IIIB cancer. NF1 patients with multiple GI tumors are at an increased risk for malignancy. Therefore, a high index of suspicion for malignancy in any patient with NF1 presenting with gastrointestinal symptoms has implications for a surgeon, warranting not only a further diagnostic investigation, but also an appropriate surgical intervention and sampling for nodal spread. Because of the possibility of a simultaneous cancer, it is crucial to assess all suspicious tumors even if the masses appear endoscopically benign.

Abstract B35: The effect of patient demographics and polyp histologic characteristics on immune gene expression in microenvironment is mediated by infiltrating microbiome

We apply new panomic distance mediation analysis with feature selection to understand the effect of polyp-infiltrating microbes on host microenvironment immune response. Multivariate omnibus distance mediation analysis (MODIMA) allows for testing for mediation in the context of multivariate exposure-mediator-response triples, such as polyp characteristics, microbiome composition, and expression, respectively. Here we extend MODIMA to allow for selection of individual components of the response and mediator responsible for mediation effects. Next we apply the method to new data from 30 colorectal polyps with simultaneous measurements of expression of 594 immune-related genes ascertained via the NanoString Immunology panel and microbiome composition via a 16S rRNA gene amplicon sequencing assay. The polyp specimens are derived from a cohort consisting of 11 female and 19 male subjects, of whom 17 are black and 25 are older than 55. The polyp biopsies come from proximal (17), distal (6), and rectal (7) locations of the colon. According to pathology evaluation, half of the polyps have evidence of high-grade dysplasia. The distribution across tubular, tubular villous, and villous histology is likewise approximately even (10, 9, and 11 specimens, respectively). Microbial DNA has been extracted from formalin-fixed, paraffin-embedded polyp tissues and analyzed using Illumina MiSeq 16S rRNA gene amplicon sequencing assay. After preprocessing, the species and genus level data have been normalized using central log ratio transformation with pseudo-counts. Species and genera with literature evidence for association with colorectal polyps and cancers have been selected for further analysis. Using these data, we evaluate the hypothesis that infiltrating microbiome mediates the immune gene expression in response to histodemographic characteristics. We expand the histodemographic data into a complete 6-way interaction design matrix. Euclidean distances have been used for all data types in all analyses. After feature selection, the joint expression of 140 immune genes is associated with polyp characteristics (dCor t-test, T = 2.9, bias corrected dCor = 0.14, p = 0.002). Likewise, 4 microbial features are jointly associated (dCor t-test, T = 2.1, bias corrected dCor = 0.10, p = 0.02). Within these data 9 genes (BCL2, CD19, CLEC6A, IRAK3, IRF3, NLRP3, PSMC2, TBX21, POLR2A) and 2 taxa (Bifidobacterium and Alistipes sp.) are jointly associated to each other (dCor t-test, T = 4.7, bias corrected dCor = 0.23, p &lt; 10−5). MODIMA analysis after feature selection suggests a significant mediation effect of these microbes on the association between polyp characteristics and the expression of the 9 genes (MODIMA stat = 0.03, p-value = 0.01). Further univariate analysis corroborates these associations and suggests a role for the infiltrating microbiome in Th1 signaling, apoptosis, and interferon and expression regulation.

Citation Format: Alexander V. Alekseyenko, Chentha Vasu, Brianna Bronsky, David N. Lewin, Shaoli Sun, Christine Bookout, John N. Baron, Kristin Wallace. The effect of patient demographics and polyp histologic characteristics on immune gene expression in microenvironment is mediated by infiltrating microbiome [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr B35.

Abstract B33: Racial differences in tumor-associated microbes in early colorectal carcinogenesis

African Americans (AA) have a higher incidence of colorectal cancer (CRC) than Caucasian Americans (CA). Emerging evidence indicates that pathogenic tumor-associated microbes (TAMs) within preinvasive lesions may promote carcinogenesis. Since AAs are more prone than CAs to robust inflammatory responses to bacteria and fungi, especially at younger ages, infiltrates in early neoplasms may differ by race and age. To study this issue, we selected a convenience sample of 35 preinvasive cases diagnosed between October 2013 and October 2016 at the Medical University of South Carolina for microbial analysis. The study pathologist diagnosed the degree of dysplasia and predominant histology for each lesion. We extracted DNA from 10-micron-thick FFPE sections and sequenced 16S rRNA gene amplicons to determine the microbial communities. We normalized the data using central log ratio transformation with pseudo-counts and selected 20 microbes previously associated with CRC for analysis. Linear regression was used to assess associations between TAMs and race while adjusting for age and sex. We also examined these associations by colorectal location (distal, proximal), degree of dysplasia (high, not high), and age (&lt; 55, 55+) using product interaction terms in our statistical models. 49% of cases were AAs, 57% were female, and 51% were less than 55 years of age. We analyzed 4 serrated polyps, 6 tubular adenoma, 16 tubulovillous adenomas, and 9 villous adenomas. 40% of the cases had high-grade dysplasia (including focal) and 51% of all lesions were from the distal colon (and rectum). We observed that AAs compared to CAs had a significantly higher microbial abundance of genus Escherichia (coef. 1.42 p=0.005), species Escherichia coli (coef. 1.38, p=0.007), and genus Shigella (coef. 1.15, p=0.02). Moreover, AAs had relatively higher TAM infiltration with these microbes in distal colorectal lesions than CAs, but there were no differences by race in the proximal colon. Finally, we observed that in comparison to older CAs, older AAs had relatively higher abundance of Escherichia (coef. 2.50; p &lt; 0.001; p for interaction=0.056), E. coli (coef. 2.45, p=0.001; p for interaction=0.04), and Shigella (coef. 2.24, p=0.001; p for interaction=0.04), but there were no significant differences in younger patients by race. Two additional microbes, Porphyromonas (p=0.01) and Ruminococcus gnavus (p=0.02), were found in lower relative abundance in AAs vs. CAs. We identified racial differences in TAMs associated with the Enterobacteriaceae family. The stronger racial differences in TAMs observed in the older but not younger patients may reflect age-related differences in bacterial clearance. In future studies, it will be important to compare the TAMs, immune reactions with markers of tumor progression.

Citation Format: Kristin Wallace, David N. Lewin, Christine Bookhout, Shaoli Sun, Brianna Bronsky, Chentha Vasu, Brenda J. Hoffman, John A. Baron, Alexander V. Alekseyenko. Racial differences in tumor-associated microbes in early colorectal carcinogenesis [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr B33.

Tumor-Infiltrating Lymphocytes and Colorectal Cancer Survival in African American and Caucasian Patients

Background: Compared with Caucasian Americans (CAs), African Americans (AAs) with colorectal cancer have poorer survival, especially younger-age patients. A robust lymphocytic reaction within colorectal cancers is strongly associated with better survival, but whether immune response impacts the disparity in colorectal cancer survival is unknown.Methods: The study population was comprised of 211 histologically confirmed colorectal cancers at the Medical University of South Carolina (Charleston, SC; 159 CAs and 52 AAs) diagnosed between Jan 01, 2000, and June 30, 2013. We constructed a lymphocyte score based on blinded pathologic assessment of the four different types of lymphocytic reactions. Cox proportional hazards regression was used to evaluate the association between the lymphocyte score and risk of death by race.Results: Colorectal cancers in AAs (vs. CAs) had a stronger lymphocytic reaction at diagnosis. A high lymphocyte score (vs. the lowest) was associated with better survival in AAs [HR 0.19; 95% confidence interval (CI), 0.04-0.99] and CAs (HR 0.47; 95% CI, 0.15-1.45). AAs with no lymphocytic reaction (vs. other categories) had poor survival HR 4.48 (1.58-12.7) whereas no difference was observed in CAs. The risk of death in AAs (vs. CA) was more pronounced in younger patients (HR 2.92; 95% CI, 1.18-7.22) compared with older (HR 1.20; 95% CI, 0.54-2.67), especially those with lymphocytic poor colorectal cancers.Conclusions: The lymphocytic reaction in tumor impacted the racial disparity in survival.Impact: Our results confirm the importance of the lymphocytic score on survival and highlight the need to fully characterize the immune environment of colorectal cancers by race. Cancer Epidemiol Biomarkers Prev; 27(7); 755-61. ©2018 AACR.

Differential Diagnosis of Hepatic Necrosis Encountered at Autopsy

The liver is subject to a variety of extrinsic and intrinsic insults that manifest with both specific and nonspecific patterns of necrosis. In the autopsy setting, these patterns are often encountered as incidental findings or even causes of death. There are several etiologies of hepatic necrosis, including toxins, drug injuries, viral infections, ischemic injuries, and metabolic disease, all of which possess overlapping gross and histologic presentations. Nonetheless, patterned necrosis in the context of clinical and demographic history allows for the forensic pathologist to develop a differential diagnosis, which may then be pruned into a specific or likely cause. The aim of the following review is to elucidate these patterns in the context of the liver diseases from which they arise with the goal developing a differential diagnosis and ultimate determination of etiology. Acad Forensic Pathol. 2018 8(2): 256-295.

Success in Implementation of a Resident In-Service Examination Review Series

OBJECTIVES

Primary pathology board certification has been correlated with senior resident in-service examination (RISE) performance. We describe our success with an annual, month-long review series.

METHODS

Aggregate program RISE performance data were gathered for 3 years prior to and 3 years following initiation of the review series. In addition, mean United States Medical Licensing Examination Step 1 and 2 Clinical Knowledge scores for residents participating in each RISE examination were obtained to control for incoming knowledge and test-taking ability. Linear models were used to evaluate differences in average RISE performance prior to and following the initiation of the review series in addition to controlling for relevant covariates.

RESULTS

Significant improvement was noted in the grand total, anatomic pathology section average, clinical pathology section average, and transfusion medicine section. Although not statistically significant, improvement was noted on the cytopathology and clinical chemistry sections. There was no significant difference in scores in hematopathology, molecular pathology, and the special topics section average. In addition, improvement in primary pathology board certification rates was also noted.

CONCLUSIONS

Institution of a month-long RISE review series demonstrated improved overall performance within our training program. The success could easily be replicated in any training program without significant disruption to an annual didactic series.

Racial Differences in Stage IV Colorectal Cancer Survival in Younger and Older Patients

INTRODUCTION

African Americans (AAs) compared with European Americans (EAs) have poorer stage-specific survival from colorectal cancer (CRC). Recent reports have indicated that the racial difference in survival has worsened over time, especially among younger patients. To better characterize this association, we used population-based Surveillance, Epidemiology, and End Results registry data to evaluate the effect of race on stage IV CRC survival in patients aged < 50 and ≥ 50 years.

PATIENTS AND METHODS

The population included 16,782 patients diagnosed with stage IV colon and rectal adenocarcinoma from January 1, 2004 and December 31, 2011. Cox proportional hazards regression was used to evaluate the association between race and other prognostic factors and the risk of death in each age group.

RESULTS

Younger AAs compared with EAs had a greater prevalence of proximal CRC at diagnosis, a factor associated with a significantly greater risk of death in both races. Among patients < 50 years old, AAs had a greater risk of death compared with EAs (hazard ratio, 1.35; 95% confidence interval, 1.20-1.51), which was attenuated in patients ≥ 50 years of age (hazard ratio, 1.10; 95% confidence interval, 1.04-1.16); P for interaction = .01.

CONCLUSION

The results revealed poor overall survival for AAs compared with EAs, especially for those < 50 years of age. The greater prevalence of proximal CRC at diagnosis among younger AAs (vs. EAs) might contribute to the racial difference in survival. Future studies are needed to understand how the colonic location affects the efficacy of treatment regimens.

Prognostic factors in relation to racial disparity in advanced colorectal cancer survival

INTRODUCTION

Colorectal cancer mortality rates are significantly greater in AA than in EA individuals, and the disparity is worsening. We investigated the relationship between race and metastatic CRC (mCRC) survival in younger and older patients.

PATIENTS AND METHODS

Using data from the Hollings Cancer Center (Charleston, SC), we studied the role of clinical, pathologic, and treatment-related factors on the disparity in survival. We carried out a retrospective cohort study of 82 mCRC patients (26 AA, 56 EA). The data source was medical record data from June 1, 2004 through May 31, 2008 with follow-up through June 30, 2010. Using Kaplan-Meier methods, we generated median survival time according to race and age (< 61, ≥ 61 years). Cox proportional hazards regression models were used to model the risk of death according to race.

RESULTS

The median age was 56.7 years for AA and 61.6 years for EA patients. Compared with EA, median survival in AA patients was 59% worse in younger patients (12.7 vs. 31.0 months) and 29% worse in older patients (11.7 vs. 16.4 months). The risk of death among younger AA compared with EA patients was 2.45 (95% confidence interval [CI], 1.15-5.23) and among older patients was 1.16 (95% CI, 0.49-2.73).

CONCLUSION

Our results highlight the importance of considering younger age, clinical prognostic markers, and tumor phenotypes as potential sources of the disparity in advanced stage CRC.

Adenovirus-mediated eNOS expression augments liver injury after ischemia/reperfusion in mice

Hepatic ischemia/reperfusion (l/R) injury continues to be a critical problem. The role of nitric oxide in liver I/R injury is still controversial. This study examines the effect of endothelial nitric oxide synthase (eNOS) over-expression on hepatic function following I/R. Adenovirus expressing human eNOS (Ad-eNOS) was administered by tail vein injection into C57BL/6 mice. Control mice received either adenovirus expressing LacZ or vehicle only. Sixty minutes of total hepatic ischemia was performed 3 days after adenovirus treatment, and mice were sacrificed after 6 or 24 hrs of reperfusion to assess hepatic injury. eNOS over expression caused increased liver injury as evidenced by elevated AST and ALT levels and decreased hepatic ATP content. While necrosis was not pervasive in any group, TUNEL demonstrated significantly increased apoptosis in Ad-eNOS infected livers. Western blotting demonstrated increased levels of protein nitration and upregulation of the pro-apoptotic proteins bax and p53. Our data suggest that over-expression of eNOS is detrimental in the setting of hepatic I/R.

Racial disparities in advanced-stage colorectal cancer survival

PURPOSE

African-Americans (AA) have a higher incidence of and lower survival from colorectal cancer (CRC) compared with European Americans (EA). In the present study, statewide, population-based data from South Carolina Central Cancer Registry are used to investigate the relationship between race and age on advanced-stage CRC survival.

METHODS

The study population was comprised of 3,865 advanced pathologically documented colon and rectal adenocarcinoma cases diagnosed between 01 January 1996 and 31 December 2006: 2,673 (69 %) EA and 1,192 (31 %) AA. Kaplan-Meier methods were used to generate median survival time and corresponding 95 % confidence intervals (CI) by race, age, and gender. Factors associated with survival were evaluated by fitting Cox proportional hazards regression models to generate hazard ratios (HR) and 95 % CI.

RESULTS

We observed a significant interaction between race and age on CRC survival (p = 0.04). Among younger patients (<50 years), AA race was associated with a 1.34 times (95 % CI 1.06-1.71) higher risk of death compared with EA. Among older patients, we observed a modest increase in risk of death among AA men compared with EA [HR 1.16 (95 % CI 1.01-1.32)] but no difference by race between women [HR 0.94 (95 % CI 0.82-1.08)]. Moreover, we observed that the disparity in survival has worsened over the past 15 years.

CONCLUSIONS

Future studies that integrate clinical, molecular, and treatment-related data are needed for advancing understanding of the racial disparity in CRC survival, especially for those <50 years old.

Abstract 5516: Race, age and advanced stage colorectal cancer survival

African Americans (AA) have worse stage-specific survival from colorectal cancer (CRC) compared to European Americans (EA), but the reasons for these differences are not well understood. To address this gap in understanding, and to examine racial differences in survival of patients with metastatic colorectal adenocarcinoma (mCRC) by age and prognostic tumor characteristics, we analyzed clinical data from Hollings Cancer Center (HCC) at the Medical University of South Carolina. Because metastatic disease has standard recommendations, a large racial difference in relative survival, and a documented change in chemotherapy usage in 2004, the dataset from HCC is ideal for this analysis. Data were collected by systematic medical record audits of patients diagnosed at HCC between June 2004 and June 2008 with follow-up through June of 2010. Analyses were designed to compare AA to EA by computing medical survival and hazard ratios (HR) and 95% CIs to model the hazard of death as a function of race, controlling for age, sex, and first-line chemotherapy treatment. We also assessed the interaction between race and age and race and clinicopathogic characteristics (i.e. histologic type, location, and grade) and their impact on survival. All tests of statistical significance were two-sided. Data from 82 (27 AA and 55 EA) patients with mCRC were evaluated. Overall survival between AA and EA differed by age, with the racial difference in survival most pronounced among younger (61 years - below the median) compared to older (≥ 61 years - above the median age) patients. Median survival among younger EA and AA was 31 months (95% CI 17-35 months) and 13 months (95% CI 6-17 months), respectively; among older patients, median survival for EA and AA was 22 months (95% CI 8-32 months) and 12 months (95% CI 3-α), respectively. In the younger group, AA had a 2.65 (95% CI 1.24-5.66) times greater risk of death than EA whereas in the older group there was no significant difference (HR 0.93 95% CI 0.39-2.21), a statistically significant interaction (p&lt;0.03). Among the younger CRC cases, AA were more likely than EA to present with mucinous, lower-grade, and colonic carcinomas, even though the AA patients were more likely to die from non-mucinous (p for interaction = 0.04), rectal (p for interaction = 0.06), and higher-grade (p for interaction = 0.12) tumors. In conclusion, the overall poorer survival among AA was concentrated in the younger patients. Despite being less prevalent at diagnosis, the results also indicated that rectal location, non-mucinous histology, and higher tumor grade were associated with poorer survival among the young AA. The reasons for the overall racial disparity being concentrated in the younger patients in unexplained; future studies may consider the role of pathomolecular markers, medical comorbidities, and treatment-related factors to further elucidate etiologies of the disparities seen in younger AA.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5516. doi:1538-7445.AM2012-5516

Slug expression enhances tumor formation in a noninvasive rectal cancer model

BACKGROUND

Epithelial-to-mesenchymal transition (EMT) is a series of molecular changes allowing epithelial cancer cells to acquire properties of mesenchymal cells: increased motility, invasion, and protection from apoptosis. Transcriptional regulators such as Slug mediate EMT, working in part to repress E-cadherin transcription. We report a novel, noninvasive in vivo rectal cancer model to explore the role of Slug in colorectal cancer (CRC) tumor development.

METHODS

For the generation of DLD-1 cells overexpressing Slug (Slug DLD-1), a Slug or empty (Empty DLD-1) pCMV-3Tag-1 (kanamycin-resistant) vector was used for transfection. Cells were evaluated for Slug and E-cadherin expression, and cell migration and invasion. For the in vivo study, colon cancer cells (parental DLD-1, Slug DLD-1, empty DLD-1, and HCT-116) were submucosally injected into the posterior rectum of nude mice using endoscopic guidance. After 28 d, tumors were harvested and tissue was analyzed.

RESULTS

Slug expression in our panel of colon cancer cell lines was inversely correlated with E-cadherin expression and enhanced migration/invasion. Slug DLD-1 cells demonstrated a 21-fold increased Slug and 19-fold decreased E-cadherin expression compared with empty DLD-1. Similarly, the Slug DLD-1 cells had significantly enhanced cellular migration and invasion. In the orthotopic rectal cancer model, Slug DLD-1 cells formed rectal tumors in 9/10 (90%) of the mice (mean volume = 458 mm(3)) compared with only 1/10 (10%) with empty DLD-1 cells.

CONCLUSION

Slug mediates EMT with enhanced in vivo rectal tumor formation. Our noninvasive in vivo model enables researchers to explore the molecular consequences of altered genes in a clinically relevant rectal cancer in an effort to develop novel therapeutic approaches for patients with rectal cancer.

Distal pancreatectomy for chronic pancreatitis: risk factors for postoperative pancreatic fistula

One of the most common complications after distal pancreatectomy is a fistula from the pancreatic remnant. Factors influencing the development of a pancreatic fistula after distal pancreatectomy have not been clearly elucidated. The records of 91 patients who underwent distal pancreatectomy for chronic pancreatitis between 1995 and 2003 were retrospectively reviewed and analyzed. Average daily volume and amylase concentration between postoperative days 2 and 20 from drains located at the pancreatic resection site were compared to clinical variables. Out of 137 pre- and intraoperative clinical variables, multivariate analysis showed serum creatinine (t = 3.05, p = 0.004), history of intraabdominal operation (t = -2.68, p = 0.01), right-sided pancreatic duct dilation (t = 2.65, p = 0.01), synchronous cholecystectomy (t = 2.53, p = 0.02), and serum albumin (t = -2.19, p = 0.04) to be independently associated with drain volume. Drain amylase concentration was linked to serum creatinine (t = 8.55, p < 0.001), blood urea nitrogen (t = -3.43, p = .001), preoperative parenteral nutrition (t = 2.56, p = .01), and serum alkaline phosphatase (t = 2.51, p = 0.01). There was no correlation between the degree of fibrosis and drain output. Technique of pancreatic transection and presence of suture closure of the pancreatic duct did not affect drain output. In conclusion, the amount and amylase concentration of postsurgical drainage after distal pancreatectomy for chronic pancreatitis is dependent on markers of renal dysfunction, malnutrition, biliary disease, and possibly inflammation. These factors, if medically reversible, should be addressed in patients who are candidates for distal pancreatectomy for chronic pancreatitis.

Inflammatory myofibroblastic tumor of the liver

Inflammatory myofibroblastic tumor is a rare benign entity formerly known as inflammatory pseudotumor. Involvement of the liver is extremely rare. There are controversies about the optimal treatment of this benign entity. Newer reports suggest an association with autoimmune sclerosing pancreatitis and primary sclerosing cholangitis. We present a case of an 18-year-old patient with biliary obstruction from a perihilar mass of the liver requiring hepatic resection. Division of the hepatic bile duct resulted in drainage of yellow, thick, gelatinous material in the presence of benign margins and absence of cholangitis. Histological examination showed a mass with fibroblastic and myofibroblastic cells set in a loose myxoid matrix containing scattered lymphocytes, consistent with an inflammatory myofibroblastic tumor. One-year recovery was uneventful. This report discusses the presentation, diagnosis, and controversies in management of this disease.

Operative management of chronic pancreatitis: longterm results in 372 patients

BACKGROUND

Operative treatment of chronic pancreatitis is indicated for patients with intractable pain after failed medical and endoscopic treatment, or for the presence of complications of the disease. This study evaluates a single-center experience with operative management of chronic pancreatitis.

STUDY DESIGN

The records of 372 consecutive patients who underwent lateral pancreaticojejunostomy (n = 184), pancreaticoduodenectomy (n = 97), or distal pancreatectomy (n = 91) for chronic pancreatitis between 1995 and 2003 were retrospectively reviewed and analyzed. Longterm outcomes were assessed by patient survey, with a median followup of 5.5 +/- 0.2 years.

RESULTS

Primary indication for operative treatment included intractable pain (n = 215), pancreatic duct disruption (n = 109), inflammatory mass (n = 42), or biliary obstruction (n = 6). Perioperative morbidity was 22%, 51%, and 29% after lateral pancreaticojejunostomy, pancreaticoduodenectomy, and distal pancreatectomy, respectively, with a perioperative mortality rate of 1%. Two hundred twenty-eight patients were available for longterm followup. Fifty-eight patients (25%) died in the followup period. Twenty-four percent of the remaining 170 patients were pain free, and 25% had good pain control after the procedure. On multivariate analysis, risk factors for poor pain control were pancreaticoduodenectomy (p < 0.01), preoperative narcotic dependence (p < 0.02), earlier abdominal operations (p < 0.02), and an absent history of gallstone pancreatitis (p < 0.05). Sixty-two percent returned to work. Quality of life assessed by SF-36 version 2 questionnaire showed norm-based scores between the 35th and 46th percentile and slightly below, but not substantially different from, a general population. New onset of endocrine and exocrine insufficiency was present in 35% and 29% of patients, respectively.

CONCLUSIONS

Operative management of chronic pancreatitis can be performed with low mortality and acceptable morbidity. Surgical treatment can provide good pain control, return patients to work, and achieve a satisfactory quality of life in the majority of patients. Longterm mortality is high in a subset of patients.

Diagnostic performance of EUS for chronic pancreatitis: a comparison with histopathology

BACKGROUND

EUS has been proposed as a minimally invasive and accurate test to detect chronic pancreatitis (CP).

OBJECTIVE

To investigate the correlation between EUS criteria and histopathology grading in patients with presumed CP.

DESIGN

Retrospective study.

SETTING AND PATIENTS

Patients who received pancreatic surgery according to presumed CP from the Medical University of South Carolina surgical database between 1995 and 2003 were identified and included if EUS was performed within 1 year before surgery. The number of EUS criteria for CP was compared with a histologic fibrosis score (FS).

MAIN OUTCOME MEASUREMENTS

Sensitivity and specificity of number of EUS criteria compared with FS.

RESULTS

Seventy-one patients were identified (38 women). Median FS was 7 (range, 0-12). Of the patients with calcifications: calcifications were detected by EUS in 30 (42%), 14 (47%) had calcifications missed by other imaging modalities, and 28 (93%) were confirmed to have abnormal histology (FS > or = 2). Of the patients without calcifications: in the 41 patients without calcifications on EUS, 36 (88%) had FS > or = 2; median FS was 5 (range, 0-12); the correlation between the number of EUS criteria and FS was low but statistically significant (r = 0.40; P = .01). Three or more EUS criteria provided the best balance of sensitivity (83.3%) and specificity (80.0%) for predicting abnormal histology.

LIMITATIONS

Retrospective study. All patients were believed to need surgery.

CONCLUSIONS

A threshold of 3 or more EUS criteria provides the best balance of sensitivity and specificity for histologic pancreatic fibrosis. Calcifications seen by EUS but missed by other imaging are common in this group of patients.

Accurate discrimination of pancreatic ductal adenocarcinoma and chronic pancreatitis using multimarker expression data and samples obtained by minimally invasive fine needle aspiration

To augment cytological diagnosis of pancreatic ductal adenocarcinoma (PDAC) in tissue samples obtained by minimally invasive endoscopic ultrasound-guided fine needle aspiration, we investigated whether a small set of molecular markers could accurately distinguish PDAC from chronic pancreatitis (CP). Expression levels of 29 genes were first determined by quantitative real-time RT-PCR in a training set of tissues in which the final diagnosis was PDAC (n=20) or CP (n=10). Using receiver operator characteristic curve analysis, we determined that the single gene with the highest diagnostic accuracy for discrimination of CP vs. PDAC in the training study was urokinase plasminogen activator receptor (UPAR; AUC value = 0.895, 95% CI=0.728-0.976). In the set of test tissues (n=14), the accuracy of UPAR decreased to 79%. However, we observed that the addition of 6 genes (EPCAM2, MAL2, CEA5, CEA6, MSLN and TRIM29; referred to as the 6-gene classifier) to UPAR resulted in high accuracy in both training and testing sets. Excluding 3 samples (out of 44; 7%) for which results of the UPAR/6-gene classifier were "undefined," the accuracy of the UPAR/6-gene classifier was 100% in training samples (n=29), 92% in 12 test samples (p=0.004 that results were randomly generated; p=0.046 that the UPAR/6-gene classifier was comparable to UPAR alone; chi2 test), 100% in 3 samples for which the initial cytological diagnosis was "suspicious" and 98% (40/41) overall. Our results provide evidence that molecular marker expression data can be used to augment cytological analysis.

Long-term results after surgery for autoimmune sclerosing pancreatitis

Autoimmune sclerosing pancreatitis (ASP) is a recently recognized cause of chronic pancreatitis. The role of operative intervention in this disease is controversial. A single center experience with 161 consecutive pancreatic resections for chronic pancreatitis was retrospectively reviewed. Operative specimens were reanalyzed and assessed for histological features of ASP. Long-term outcome was assessed by patient survey. Eight patients were identified with histological changes consistent with ASP. The pancreatic anatomic configuration according to intraoperative findings and preoperative radiographic evaluation was categorized into (1) diffusely enlarged pancreas (n = 4), (2) localized mass (n = 2), or (3) refractory pancreatic duct disruption without pancreatic enlargement (n = 2). Five patients underwent pancreaticoduodenectomy and three patients underwent distal pancreatectomy. Perioperative morbidity, operative time, and intraoperative estimated blood loss were similar to the same operation for other etiologies of chronic pancreatitis. Biliary obstruction occurred in two patients. Seven patients were alive 5 +/- 0.4 years after operation. Good quality of life measured by the SF-36 questionnaire was present in 4 of 7 patients surveyed. Good pain control was achieved with return to work in 5 of 7 patients. Two patients with poor pain control received glucocorticosteroids therapy without improvement in symptoms. Patients with ASP and a mass suspicious for malignancy or refractory duct disruption require operative intervention. Early postoperative outcome, long-term pain control, and improvement in quality of life appear to be good.

Reoperative Surgery for Chronic Pancreatitis: Is It Safe?

INTRODUCTION

Eleven percent to fifty-six percent of patients do not achieve adequate pain relief with initial operative treatment for chronic pancreatitis, and reoperations for recurrent or persistent pain are common. This study evaluates the influence of prior pancreatic procedures on operative morbidity for chronic pancreatitis.

METHODS

The records of 336 consecutive patients who underwent pancreaticoduodenectomy (PD, n=78), lateral pancreaticojejunostomy (LPJ, n=152), distal pancreatectomy (DP, n=83), transduodenal sphincteroplasty (SP, n=20), and total pancreatectomy (TP, n=3) for chronic pancreatitis were retrospectively reviewed and analyzed.

RESULTS

Seventy-four patients underwent reoperation after failed prior pancreatic surgery. Patients with de novo pancreatic operations had a similar complication rate as those with reoperation (PD: 48% versus 65%, P>0.05; LPJ: 23% versus 23%, P>0.05; DP: 26% versus 28%, P>0.05; SP: 21% versus 100%, P>0.05). Major complications such as pancreatic leak or abdominal abscess were similar in the two groups. Minor complications such as delayed gastric emptying or wound infections were more common in the reoperation group. There was no difference in postoperative hospital length of stay.

CONCLUSIONS

Patients who undergo reoperative surgery for chronic pancreatitis have an increased risk for minor perioperative complications. The overall complication rate and the incidence of major complications are similar compared to de novo procedure. Reoperative surgery therefore appears feasible and safe in experienced hands.

Do preoperative pancreatic stents increase operative morbidity for chronic pancreatitis?

BACKGROUND/AIMS

Recent studies suggest that preoperative placement of bile duct stents increases morbidity after pancreatic surgery. The influence of pancreatic duct stenting on outcome after pancreatic surgery is unknown.

METHODOLOGY

The records of 264 consecutive patients who underwent lateral pancreaticojejunostomy, pancreaticoduodenectomy, or distal pancreatectomy for chronic pancreatitis were retrospectively reviewed and analyzed.

RESULTS

There were 137 patients who received preoperative endoscopic pancreatic stents. The remainder underwent preoperative ERCP without stent placement. Both groups had a similar stage of disease measured by endoscopic, clinical, and histological findings. The overall postoperative morbidity was higher in the stent group (19.7% vs. 42.3%, p<0.001, odds ratio 3.0). Intra-abdominal complications occurred more frequently in the stent group (10.2% vs. 32.8%, p<0.001), including a difference in pancreatic leaks. There was no difference in extra-abdominal complications (10.2% vs. 13.1%) and mortality (1.6% vs. 1.5%).

CONCLUSIONS

Patients who undergo pancreatic duct stenting and require surgical drainage at a later point have a threefold increased risk for peri-operative complications. An increase in intra-abdominal complications might be related to stent associated pancreatic duct injuries, stent occlusion, and bacterial colonization of the stent.

Accurate discrimination of Barrett's esophagus and esophageal adenocarcinoma using a quantitative three-tiered algorithm and multimarker real-time reverse transcription-PCR

Esophageal adenocarcinoma (EA) is increasing faster than any other cancer in the U.S. In this report, we first show that EA can be distinguished from normal esophagus (NE) and esophageal squamous cell carcinoma by plotting expression values for EpCam, TFF1, and SBEM in three-dimensional Euclidean space. For monitoring progression of Barrett's esophagus (BE) to EA, we developed a highly sensitive assay for limited quantities of tissue whereby 50 ng of RNA are first converted to cDNA using 16 gene-specific primers. Using a set of training tissues, we developed a novel quantitative three-tiered algorithm that allows for accurate (overall accuracy = 61/63, 97%) discrimination of BE versus EA tissues using only three genes. The gene used in the first tier of the algorithm is TSPAN: samples not diagnosed as BE or EA by TSPAN in the first tier are then subjected to a second-tier analysis using ECGF1, followed by a third-tier analysis using SPARC. Addition of TFF1 and SBEM to the first tier (i.e., a five-gene marker panel) increases the overall accuracy of the assay to 98% (62/63) and results in mean molecular diagnostic scores (+/- SD) that are significantly different between EA and BE samples (3.19 +/- 1.07 versus -2.74 +/- 1.73, respectively). Our results suggest that relatively few genes can be used to monitor progression of BE to EA.

Granular cell tumor of the biliary system: a report of 2 cases with cytologic diagnosis on endoscopic brushing

BACKGROUND

Granular cell tumors (GCTs) of biliary system are rare. GCTs show a striking preponderance for young, black females, who generally present with obstructive jaundice. To our knowledge, these are the first 2 reports of GCT of biliary system identifed on endoscopic brushing cytology.

CASES

In case 1, a 24-year-old, black woman presented with a 5-month history of pruritus. Radiographic studies demonstrated a mass in the distal common bile duct. Endoscopic biopsy and bile duct brushing were diagnosed as GCT. A Whipple procedure was confirmatory of GCT. In case 2, a 38-year-old, black female presented with a 7-month history of pruritus and jaundice. Radiographic studies showed a stricture of the common hepatic duct at the hilum. Endoscopic brushing cytology of the stricture yielded only a few sheets of granular cells that were missed on initial screening. Suspicion of cholangiocarcinoma prompted surgery, and final histopathology showed GCT. Both patients were well 1 1/2 and 6 years after presentation.

CONCLUSION

GCT of the bile duct can be diagnosed on endoscopic brushing and should be considered in the cytologic differential diagnosis in the appropriate clinical settings.

Are ulcers a marker for invasive carcinoma in Barrett's esophagus? Data from a diagnostic variability study with clinical follow-up

OBJECTIVES

We correlated follow-up information from 138 patients with Barrett's esophagus and varying degrees of dysplasia with the presence of ulcers.

METHODS

A group of pathologist participants were asked to contribute patients' initial biopsy slides showing Barrett's esophagus (BE) without dysplasia and with epithelial changes indefinite for dysplasia, low grade dysplasia (LGD), high grade dysplasia (HGD), and adenocarcinoma. From the initial 250 cases used for a diagnostic reproducibility study, follow-up information was available for 138 patients.

RESULTS

There were 44 cases submitted as BE, 22 as BE with epithelial changes indefinite for dysplasia, 26 as BE with LGD, 33 as BE with HGD, and 13 as BE with adenocarcinoma. Ulcers were present in 35/138 cases (25%), including 3/44 cases of BE without dysplasia (7%), 2/22 cases of BE with epithelial changes indefinite for dysplasia (9%), 0/26 cases of BE with LGD (0%), 10/33 cases of BE with HGD (30%), and 7/13 cases of BE with adenocarcinoma (54%). On follow-up, there were no invasive carcinomas detected among the BE without dysplasia group (median follow-up = 38.5 months). Adenocarcinomas were detected in 4/22 cases (18%) submitted as BE with epithelial changes indefinite for dysplasia at 19, 55, 60, and 62 months and in 4/26 cases (15%) of BE with LGD at 9, 9, 11, and 60 months. None of these carcinomas occurred in cases in which an ulcer was present in the initial biopsy specimen. Among the 33 HGD cases, 20 (60%) were found to have adenocarcinoma on subsequent resection specimens. The presence of an ulcer with HGD increased the likelihood of finding carcinoma in the resection specimen, as 8/10 biopsies (80%) of HGD patients with ulcers had carcinoma, compared to 12/23 biopsies (52%) of HGD patients without ulcers. All of the cases interpreted as adenocarcinomas on biopsy were found either to have invasive carcinoma on esophageal resection or to have metastases that were demonstrated in unresectable patients.

CONCLUSION

If an ulcer accompanies HGD in a biopsy specimen from a patient with BE, it is likely that invasive carcinoma is also present at that time.

Hepatopulmonary syndrome occurring after orthotopic liver transplantation

Hepatopulmonary syndrome (HPS) is an infrequent complication of liver cirrhosis. Orthotopic liver transplantation (OLT) has gained increasing acceptance as a treatment modality for HPS, although there have been reports of HPS developing after OLT with documented recurrence of cirrhosis. We describe the case of a 9-year-old boy who underwent OLT at 7 months of age because of biliary atresia. He subsequently developed HPS in the setting of chronic rejection without cirrhosis or evidence of portal hypertension. Re-OLT resulted in resolution of HPS and a good clinical outcome.

The utility of EUS and EUS-guided fine needle aspiration in detecting celiac lymph node metastasis in patients with esophageal cancer: a single-center experience

BACKGROUND

The aims of this study were to determine the utility of EUS and EUS-guided fine needle aspiration (EUS-FNA) in the detection and confirmation of celiac lymph node metastasis in patients with esophageal cancer and to define EUS features predictive of celiac lymph node metastasis in these patients.

METHODS

The records of 211 patients with esophageal cancer who underwent EUS staging were reviewed. The operating characteristics of EUS were determined in patients where either surgery, EUS-FNA of a celiac lymph node, or both were performed (n = 102). The association between selected variables and the presence of celiac lymph node metastasis was evaluated by univariate and multivariable analyses.

RESULTS

EUS in 48 patients provided a true-positive diagnosis of celiac lymph node involvement, a false-positive and false-negative result, respectively, in 6 and 14 patients, and a true-negative diagnosis in 34 patients. The sensitivity of EUS in detecting celiac lymph node was 77% (95% CI [67, 88]), specificity 85% (95% CI [74, 96]), negative predictive value 71% (95% CI [58, 84]), and the positive predictive value 89% (95% CI [81, 97]). EUS-FNA was performed in 94% (51/54) of patients with celiac lymph nodes. The accuracy of EUS-FNA in detecting malignant celiac lymph nodes was 98% (95% CI [90, 100]). Advanced T-stage, the need for dilation, detection of peritumoral lymph nodes, and black race were associated with celiac lymph node involvement. In multivariable analysis, advanced T-stage was the strongest predictor of celiac lymph node involvement.

CONCLUSION

EUS and EUS-FNA are highly accurate in detecting and confirming celiac lymph nodes metastasis. Depth of tumor invasion as assessed by EUS is a strong predictor of celiac lymph node metastasis in patients with esophageal cancer.

Dysplasia as a predictive marker for invasive carcinoma in Barrett esophagus: a follow-up study based on 138 cases from a diagnostic variability study

The objective of endoscopic surveillance in Barrett esophagus (BE) is to assess the risk of subsequent development of invasive carcinoma. Criteria for morphologic evaluation of dysplasia, the presumed precursor lesion, have been established, although there are surprisingly few data in the literature correlating biopsy diagnosis of dysplasia with outcome. We collected follow-up information on 138 patients with BE whose initial endoscopic biopsy specimens had been selected for submission in an interobserver variability study performed by 12 pathologists with special interest in gastrointestinal pathology and reviewed blindly twice each by all the participants. Cases were scored as BE with no dysplasia, atypia indefinite for dysplasia (IND), low-grade dysplasia (LGD), high-grade dysplasia (HGD), intramucosal carcinoma, and frankly invasive carcinoma, thus generating 24 scores on each biopsy specimen. Clinical follow-up was obtained and correlated with both the submitting diagnoses and majority diagnoses. Kaplan-Meier statistics were used to compare both the submitting and majority diagnoses with outcome using detection or documentation of invasive carcinoma as the endpoint. Using the submitting diagnoses, no invasive carcinomas were detected in 44 cases diagnosed as BE (median follow-up, 38.5 months). Carcinomas were detected in 4 of 22 (18%) cases submitted as IND (median progression-free survival of 62 months), in 4 of 25 (15%) cases of LGD (median progression-free survival of 60 months), in 20 of 33 cases of HGD (median progression-free survival, 8 months), and all 13 (100%) cases submitted as adenocarcinoma. Grade on initial biopsy correlated significantly with progression to invasive carcinoma (log-rank P =.0001). Majority diagnosis was achieved in 99 of the cases. Using the majority diagnoses, no invasive carcinomas were found in 50 cases of BE (median follow-up, 48 months), and carcinomas were detected in 1 of 7 (14%) IND cases (80% progression-free survival at 2 months), 3 of 15 (20%) LGD (median progression-free survival, 60 months), 9 of 15 (60%) HGD (median progression-free survival, 7 months), and all 12 (100%) carcinoma. Initial grading again correlated significantly with progression to invasive carcinoma (log-rank P =.0001). However, there were 39 cases without a majority diagnosis. Among these, no carcinomas developed in 8 cases with an average score between BE and IND. Carcinomas were detected in 9 of 21 (43%) cases with an average score between IND and LGD, and 7 of 10 (70%) cases with an average score between LGD and HGD. There were ulcers in 8 of 39 cases (20%) of the "no-majority" group and in 13 of 99 (13%) of the majority cases. Of 21 total ulcerated cases, cancer was demonstrated in 15 (71%) of these on follow-up. These data support combining the IND and LGD categories for surveillance purposes. Cases without dysplasia may be followed up conservatively. The data obtained from submitted diagnoses as opposed to those from blind review suggest that knowledge of the clinical findings aids in diagnosis. The data also support the assertion that HGD is strongly associated with invasive carcinoma. Rebiopsy of ulcerated areas should be considered because they may harbor malignancy. Histologic grading of dysplasia using established criteria is a powerful prognosticator in BE. HUM PATHOL 32:379-388.

Reproducibility of the diagnosis of dysplasia in Barrett esophagus: a reaffirmation

Morphologic assessment of dysplasia in Barrett esophagus, despite limitations, remains the basis of treatment. We rigorously tested modified 1988 criteria, assessing intraobserver and interobserver reproducibility. Participants submitted slides of Barrett mucosa negative (BE) and indefinite (IND) for dysplasia, with low-grade dysplasia (LGD) and high-grade dysplasia (HGD), and with carcinoma. Two hundred fifty slides were divided into 2 groups. The first 125 slides were reviewed, without knowledge of the prior diagnoses, on 2 occasions by 12 gastrointestinal pathologists without prior discussion of criteria. Results were analyzed by kappa statistics, which correct for agreement by chance. A consensus meeting was then held, establishing, by group review of the index 125 slides, the criteria outlined herein. The second 125-slide set was then reviewed twice by each of the same 12 pathologists, and follow-up kappa statistics were calculated. When statistical analysis was performed using 2 broad diagnostic categories (BE, IND, and LG v HG and carcinoma), intraobserver agreement was near perfect both before and after the consensus meeting (mean kappa = 0.82 and 0.80). Interobserver agreement was substantial (kappa = 0.66) and improved after the consensus meeting (kappa = 0.70; P =.02). When statistical analysis was performed using 4 clinically relevant separations (BE; IND and LGD; HGD; carcinoma), mean intraobserver kappa improved from 0.64 to 0.68 (both substantial) after the consensus meeting, and mean interobserver kappa improved from 0.43 to 0.46 (both moderate agreement). When statistical analysis was performed using 4 diagnostic categories that required distinction between LGD and IND (BE; IND; LGD; HGD and carcinoma), the pre-consensus meeting mean intraobserver kappa was 0.60 (substantial agreement), improving to 0.65 after the meeting (P <.05). Interobserver agreement was poorer, with premeeting and postmeeting mean values unchanged (kappa = 0.43 at both times). Interobserver agreement was substantial for HGD/carcinoma (kappa = 0.65), moderate to substantial for BE (kappa = 0.58), fair for LGD (kappa = 0.32), and slight for IND (kappa = 0.15). The intraobserver reproducibility for the diagnosis of dysplasia in BE was substantial. Interobserver reproducibility was substantial at the ends of the spectrum (BE and HG/carcinoma) but slight for IND. Both intraobserver and interobserver variation improved overall after the application of a modified grading system developed at a consensus conference but not in separation of BE, IND, and LGD. The criteria used by the group are presented. HUM PATHOL 32:368-978.

Endoscopic ultrasonography with fine-needle aspiration: an accurate and simple diagnostic modality for sarcoidosis

BACKGROUND AND STUDY AIMS

Sarcoidosis is a chronic multisystem granulomatous disease that is often diagnosed after a finding of hilar and mediastinal lymphadenopathy on a chest radiograph. This often requires further evaluation by transbronchial biopsy or other clinical parameters. The present study is a descriptive, retrospective one using endoscopic ultrasound with fine-needle aspiration (EUS-FNA) of mediastinal lymph nodes in seven patients with sarcoidosis.

PATIENTS AND METHODS

Among 108 consecutive patients who underwent EUS-FNA of mediastinal lymph nodes for various clinical indications between July 1994 and October 1997, seven patients were found to have sarcoidosis on EUS-FNA, and the EUS morphology was studied in these patients.

RESULTS

Sarcoidosis was diagnosed in seven patients using endosonographic characteristics and clinical follow-up. EUS with FNA showed cytological evidence of sarcoidosis in six patients. Seven patients were found to have subcarinal lymph nodes, and six patients had abnormally enlarged aortopulmonary (AP) window lymph nodes. The nodes in all patients had three endosonographic criteria for malignancy. The long axis of the largest mediastinal lymph nodes measured 3.44+/-1.42 cm (range 1.8-6.0 cm). The short axis measured 2.50+/-0.69 (range 1.0-4.0 cm). The average number of nodes seen in each patient was 2.80+/-0.75 (range 2-4). The nodes in all seven patients were discrete and well demarcated. A central hyperechoic strand was evident in these nodes in four patients (57%). There were no complications.

CONCLUSIONS

Mediastinal lymph nodes in patients with sarcoidosis appear to have specific echo characteristics, and EUS-FNA can be used for confirmatory tissue diagnosis.

Accuracy of four commercially available serologic tests, including two office-based tests and a commercially available 13C urea breath test, for diagnosis of Helicobacter pylori

BACKGROUND

Diagnosis of H. pylori infection may be made by endoscopic (invasive) tests, or by nonendoscopic (noninvasive) tests. Our aim was to evaluate recently available nonendoscopic tests, including two office-based serologic tests and a commercially available 13C urea breath test.

METHODS

Gastric biopsy specimens (for culture and stain) from 178 patients (mean age 46 +/- 13.3 years, 79 men and 99 women), none of whom had received anti-H. pylori therapy, were tested for H. pylori infection. These tests were compared against two commercial serum IgG antibody immunoassays (Biowhittaker's Pyloristat, and Quidel), 2 office-based serum qualitative IgG antibody tests (FlexSure HP, and QuickVue One-Step), the Meretek 13C urea breath test, and the CLOtest (a biopsy urease test).

RESULTS

The breath test (n = 147) had the best accuracy (96%) of the noninvasive tests studied. The serologic tests had similar accuracy to one another (84%-90%). The major drawback of the serologic tests was suboptimal specificity (75%-87%). Diagnosis of H. pylori based on the two office-based tests were not significantly different compared to the quantitative IgG antibody tests. The CLOtest had an accuracy of 97%.

CONCLUSIONS

The Meretek 13C urea breath test is an excellent test, but is considerably more expensive than serologic tests. The FlexSure HP and the QuickVue One-Step office-based qualitative IgG serologic antibody tests gave similar results to laboratory based quantitative antibody tests, and are acceptable for initial diagnosis of H. pylori infection. The advantages of the office-based tests are low cost, simplicity, and immediacy of results.

Immunohistochemical evaluation of K-ras, p53, and HER-2/neu expression in hyperplastic, dysplastic, and carcinomatous lesions of the pancreas: evidence for multistep carcinogenesis

The pathobiology of precursor lesions leading to invasive pancreatic adenocarcinoma remains a controversial area, but knowledge of the mechanisms of tumorigenesis may lead to possibly earlier detection, prevention, and treatment in the future. We hypothesize that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions and are part of a continuous developmental spectrum evolving into ductal adenocarcinoma of the pancreas. To further define this sequence, we studied the immunohistochemical markers HER-2/neu, K-ras, and p53 in 15 adenocarcinomas and 15 nonmalignant specimens of the pancreas. The 15 nonmalignant specimens of the pancreas included both normal pancreas and chronic pancreatitis. Overall, HER-2/neu was positive in normal ducts, ductal hyperplasia, dysplasia, and carcinoma cells in 0 of 30, 11 of 20 (55%), 10 of 15 (67%), and 12 of 15 (80%), respectively, with progressive increase in the intensity of staining; p53 was positive in 1 of 30 (3%), 0 of 20, 3 of 15 (20%), and 13 of 15 (80%), respectively, and K-ras was positive in 1 of 30 (3%), 6 of 20 (30%), 11 of 15 (73%), and 8 of 15% (53%), respectively. These data support the hypothesis that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions, and, in a fashion similar to that in colorectal tumorigenesis, pancreatic cancer seems to accumulate progressive genetic alterations.

Prospective comparison of H&E, Giemsa, and Genta stains for the diagnosis of Helicobacter pylori

BACKGROUND

H. pylori is more easily visualized with special stains than with H&E, but this adds time and expense to the diagnostic workup. We sought to determine if the diagnostic accuracy was improved with special stains.

METHODS

One hundred-one patients had two "jumbo" biopsies taken from the gastric antrum and two from the body for examination with H&E, Genta, and Giemsa stains. Four separate biopsy specimens were also taken from the antrum and the body for culture and for three types of rapid urease test, and 13C-urea breath tests were also performed. Mixed, coded biopsies were assessed for H. pylori, and density was scored from 0 to 4. A case was considered positive for H. pylori if culture was positive, two rapid urease tests and a urea breath test were positive, or two different stains were positive. Biopsy specimens were excluded from analysis if the slides were missing or there was inadequate tissue for review, or if the specimen showed a lack of staining.

RESULTS

Fifty-two (13%) of 404 specimens were excluded because of a poor Genta stain. Sensitivities were comparable for the three stains (H&E, 92%; Giemsa, 88%; Genta, 91%), while H&E specificity (89%) was significantly lower than that of the special stains (98%). Sensitivity for all three stains was significantly lower at low (grade 0 to 1) H. pylori density than at high (grade 2 to 4) density (H&E, 70% vs 98%; Giemsa, 64% vs 96%; Genta, 66% vs 97%), and 20 of 22 false positives were grade 1.

CONCLUSIONS

The sensitivities of H&E and special stains are comparable at around 90%, but the specificity of H&E is significantly lower. The Giemsa stain appears to be the preferred stain for H. pylori diagnosis on the basis of its good sensitivity, excellent specificity, and lack of technical difficulty in preparation. However, H&E provides excellent accuracy when more than minimal (grade 1) H. pylori density is present.

The influence of warming on rapid urease test results: a prospective evaluation

BACKGROUND

A rapid urease test is the initial test of choice for the diagnosis of Helicobacter pylori at endoscopy. Incubating the CLOtest at 30 degrees to 40 degrees C is recommended, but this decreases simplicity and requires the purchase of additional equipment. We compared results of testing at room temperature versus incubation at 37 degrees C.

METHODS

Four biopsy specimens were taken from the same portion of the antrum in 200 patients undergoing upper endoscopy. One was placed in each of two CLOtests and two were sent for histologic examination. One CLOtest was incubated at 37 degrees C while the other remained at room temperature (22 degrees to 24 degrees C). Tests were checked every 15 minutes for the first 3 hours, every 1 hour from 3 to 6 hours, and at 24 hours.

RESULTS

One hundred twenty one (61%) of 200 patients had H. pylori on histologic examination. Median time to a positive test was 3/4 hour at 37 degrees C and 1 hour at room temperature (p < 0.0001). Sensitivities were greater at 37 degrees C at 1 hour (70% vs 49%; p = 0.001) and 2 hours (86% vs 76%, p = 0.07), but were nearly identical thereafter. Specificities, identical at the two temperatures, were 99% to 100% at 1 to 6 hours and 95% at 24 hours. The CLOtest became positive more rapidly at 37 degrees C in 72% of patients: more than 1/2 hour faster in 42%; and more than 1 hour faster in 16% of patients.

CONCLUSIONS

Incubation of the CLOtest at 37 degrees C hastens the time to a positive test in most patients, although the time saved is usually less than 1 hour. Sensitivity is improved when the test is read at 1 to 2 hours, but no improvement is seen beyond this time. Specificity is not influenced by warming. CLOtest incubation at 37 degrees C should be done if a final reading of the CLOtest is desired within 1 to 2 hours of biopsy.

Orthotopic liver transplantation for bone-marrow transplant-associated veno-occlusive disease and graft-versus-host disease of the liver

Bone marrow transplantation (BMT) is a highly successful and curative therapy for many primary hematologic malignancies. However, hepatic dysfunction and failure are important causes of morbidity and mortality in this patient group after BMT. Hepatic failure can occur as a result of involvement by graft-versus-host disease (GVHD) or as a result of veno-occlusive disease (VOD). Therapies for these complications are often ineffective, especially for VOD, as approximately one fourth of patients develop irreversible liver disease and die of multiorgan failure. Accordingly, we have reviewed our center's experience with orthotopic liver transplantation (OLT) to manage the hepatic complications of BMT. We describe two patients who were treated with OLT after developing hepatic failure post-BMT. One patient had VOD with mild cutaneous and gastrointestinal GVHD; in the other patient, the pathophysiologic process affecting the liver was severe GVHD. Based on our center's experience and review of the literature, we believe OLT should be considered in patients with severe hepatic dysfunction post-BMT.

Pathologist-gastroenterologist interaction. The changing role of the pathologist

The importance of interaction between clinicians and pathologists is examined in the setting of gastroenterology and gastrointestinal disease, and the importance of communication is emphasized. The endoscopist must provide the pathologist with information about the patient, including results of the gross examination, biopsy location, relevant clinical history, bowel preparation, and current medications. The pathologist must provide a reproducible and useful report that answers the clinical questions posed by the endoscopist. This consultation between the gastroenterologist and pathologist provides the framework for proper patient care.