Clinical and Pathological Correlation in Concomitant Celiac Disease and Eosinophilic Esophagitis Suggests Separate Etiologies.

Introduction. Recently, an increased risk of celiac disease or eosinophilic esophagitis has been postulated among patients with either of these disorders, prompting some to suggest a common underlying mechanism, whereas others maintain that their co-existence is coincidental. Methods. We compared clinical and pathological features of 29 patients meeting criteria for both celiac disease and eosinophilic esophagitis to 26 celiac disease and 26 eosinophilic esophagitis controls to determine whether any distinguished study patients from controls. Results. Eight (28%) study patients presented with symptoms of both celiac disease and eosinophilic esophagitis, whereas 14 (48%) had celiac disease symptoms only and 5 had (17%) esophageal symptoms only. Study patients had similar autoimmune and atopic conditions seen in both control groups. Histological severity of disease, including Marsh II-III duodenal histology (study specimens: 87%; controls: 89%), mean peak esophageal eosinophil counts (study specimens: 55/400x field; controls: 80/400X field, P = .1), and presence of eosinophil microabscesses, scale crust, and subepithelial fibrosis were also similar to controls. Gluten-free diet resolved celiac disease-related symptoms (19 of 20, 95%) and histology (10 of 12, 83%), but not esophageal symptoms or eosinophilia in most study patients. Conclusion. Patients with concomitant celiac disease and eosinophilic esophagitis lack distinguishing features compared to controls with celiac disease or eosinophilic esophagitis alone. The occurrence of both disorders is likely coincidental in most cases.

Patterns of gastrointestinal injury in patients with chronic kidney disease: Comparison of cases with and without sevelamer crystals.

AIMS: Sevelamer is a phosphate-binding resin implicated in gastrointestinal (GI) injury. This study aimed to investigate the role of sevelamer in GI injury among chronic kidney disease (CKD) patients. METHODS AND RESULTS: The study included 17 CKD patients (cases) with and 18 CKD patients (comparisons) without sevelamer crystals in specimens. All cases were on sevelamer. Six comparison patients were also taking sevelamer, but crystals were absent in tissue sections. The comparison group was thus subclassified into patients who were and were not taking sevelamer. The frequency of underlying disorders was similar between two groups, including hypertension (cases = 82%; comparisons = 78%) and diabetes mellitus (cases = 53%, comparisons = 50%). The most common presentation was GI bleeding (cases = 41%, comparisons = 33%). Predominant histological patterns were also similar, with ulcers (cases = 42%; comparisons = 39%) and acute ischaemia (cases = 35%; comparisons = 28%) being predominant in both cohorts. Of note, sevelamer was present with amyloidosis and cytomegalovirus in one study case each. Two study patients who continued sevelamer had follow-up biopsies; one showed persistent ulceration and the other appeared normal. Crystals were absent in both. CONCLUSIONS: GI injury in CKD patients in both groups had similar features regardless of presence of sevelamer, suggesting that it adheres to tissue rather than causes injury. The study highlights other histologically identifiable causes of intestinal injury, as well as injuries unassociated with sevelamer in patients undergoing therapy. Therefore, physicians should be cautious in attributing GI injuries to sevelamer to avoid overlooking other causes and unnecessary treatment discontinuation.

Mast Cell Disorders of the Gastrointestinal Tract: Clarity out of Chaos.

Pathologists are increasingly asked to evaluate mast cell infiltrates in the gastrointestinal tract when there is clinical concern for systemic mastocytosis or a variety of functional disorders, including irritable bowel syndrome and mast cell activation syndrome. Neoplastic mast cells have established quantitative, morphologic, and immunohistochemical features that facilitate their identification in gastrointestinal mucosal biopsies. Specific qualitative and quantitative findings are lacking for inflammatory mast cell-mediated disorders. This review covers histopathologic features of mast cell disorders that affect the gastrointestinal tract and offers practical guidance for their assessment in mucosal biopsies.

Stabilized Window for Intravital Imaging of the Murine Pancreas.

The physiology and pathophysiology of the pancreas are complex. Diseases of the pancreas, such as pancreatitis and pancreatic adenocarcinoma (PDAC) have high morbidity and mortality. Intravital imaging (IVI) is a powerful technique enabling the high-resolution imaging of tissues in both healthy and diseased states, allowing for real-time observation of cell dynamics. IVI of the murine pancreas presents significant challenges due to the deep visceral and compliant nature of the organ, which make it highly prone to damage and motion artifacts. Described here is the process of implantation of the Stabilized Window for Intravital imaging of the murine Pancreas (SWIP). The SWIP allows IVI of the murine pancreas in normal healthy states, during the transformation from the healthy pancreas to acute pancreatitis induced by cerulein, and in malignant states such as pancreatic tumors. In conjunction with genetically labeled cells or the administration of fluorescent dyes, the SWIP enables the measurement of single-cell and subcellular dynamics (including single-cell and collective migration) as well as serial imaging of the same region of interest over multiple days. The ability to capture tumor cell migration is of particular importance as the primary cause of cancer-related mortality in PDAC is the overwhelming metastatic burden. Understanding the physiological dynamics of metastasis in PDAC is a critical unmet need and crucial for improving patient prognosis. Overall, the SWIP provides improved imaging stability and expands the application of IVI in the healthy pancreas and malignant pancreas diseases.

Infectious Mimics of Inflammatory Bowel Disease.

Distinguishing inflammatory bowel disease (IBD) from its mimics remains a diagnostic challenge for surgical pathologists. Several gastrointestinal infections produce inflammatory patterns that overlap with typical findings of IBD. Although stool culture, PCR, and other clinical assays may identify infectious enterocolitides, these tests may not be performed or the results may be unavailable at the time of histologic evaluation. Furthermore, some clinical tests, including stool PCR, may reflect past exposure rather than an ongoing infection. It is important for surgical pathologists to be knowledgeable about infections that simulate IBD to generate an accurate differential diagnosis, perform appropriate ancillary studies, and prompt clinical follow-up. This review covers bacterial, fungal, and protozoal infections in the differential diagnosis of IBD.

What Is the Value of Counting Mast Cells in Gastrointestinal Mucosal Biopsies?

Neoplastic and nonneoplastic mast cell disorders can cause diarrhea, nausea, and abdominal pain that result from heightened release of mast cell mediators. Systemic mastocytosis is characterized by neoplastic mast cell aggregates in the bone marrow and other sites, particularly the skin and gastrointestinal tract. In this situation, extramedullary mast cell aggregates display atypical morphology, with aberrant immunostaining for CD25 in addition to staining for other mast cell markers, such as mast cell tryptase and CD117. Morphologically normal mast cells have also been implicated in nonneoplastic conditions. For example, increased mast cell numbers have been reported in the mucosal biopsy samples from patients with irritable bowel syndrome and hereditary alpha-tryptasemia. Patients with mast cell activation syndrome presumably experience symptoms related to the aberrant elaboration of histamine and other mediators from normal-appearing mast cells present in normal numbers. Unfortunately, similarities in terminology among these biologically distinct clinical conditions have caused considerable diagnostic confusion among clinical colleagues, resulting in frequent requests for pathologists to quantify and characterize mast cells in normal gastrointestinal biopsy samples from patients with diarrheal symptoms. The purpose of this review is to summarize the available data related to mast cell assessment in the gastrointestinal tract and provide pathologists with practical information so that they can help their clinical colleagues manage patients with presumed mast cell disorders.

Interobserver Variability in Assessment of Depth of Submucosal Invasion for Colonic Endoscopic Resections Among Subspecialized Gastrointestinal Pathologists.

CONTEXT.­: Recent data support that low-risk submucosally invasive (pT1) colonic adenocarcinomas (ie, completely resected tumors that lack high-grade morphology, tumor budding, and lymphovascular invasion) are considered cured via endoscopic resection, provided that the submucosal invasion is less than 1000 µm. Hence, the pathologists' assessment of depth of submucosal invasion may guide further management (ie, surveillance versus colectomy). OBJECTIVE.­: To assess interobserver concordance among gastrointestinal pathologists in measuring submucosal depth of invasion in colonic endoscopic resections. DESIGN.­: Six gastrointestinal pathologists from 5 academic centers independently measured the greatest depth of submucosal invasion in micrometers on 52 hematoxylin-eosin-stained slides from colonic endoscopic specimens with pT1 adenocarcinomas, per published guidelines (round 1 scoring). Two separate measurements (round 2 scoring) were subsequently performed by each pathologist following a consensus meeting, (1) from the surface of the lesion and (2) from the muscularis mucosae, and pathologists were asked to choose their (3) "real-life (best)" assessment between the first 2 measurements. Interobserver agreement was assessed by the intraclass correlation coefficient (ICC) and Cohen κ statistics. RESULTS.­: Round 1 had poor ICC (0.43; 95% CI, 0.31-0.56). Round 2 agreement was good when measuring from the surface (ICC = 0.83; 95% CI, 0.76-0.88) but moderate (ICC = 0.59; 95% CI, 0.47-0.70) when measuring from the muscularis mucosae and became poor (ICC = 0.49; 95% CI, 0.36-0.61) for the best-assessment measurement. CONCLUSIONS.­: Our findings indicate that clearer and reproducible guidelines are needed if clinical colleagues are to base important management decisions on pathologists' estimate of the depth of submucosal invasion in colonic endoscopic resections.

SWIP-a stabilized window for intravital imaging of the murine pancreas.

Pancreatitis and pancreatic ductal adenocarcinoma (PDAC) are grave illnesses with high levels of morbidity and mortality. Intravital imaging (IVI) is a powerful technique for visualizing physiological processes in both health and disease. However, the application of IVI to the murine pancreas presents significant challenges, as it is a deep, compliant, visceral organ that is difficult to access, easily damaged and susceptible to motion artefacts. Existing imaging windows for stabilizing the pancreas during IVI have unfortunately shown poor stability for time-lapsed imaging on the minutes to hours scale, or are unable to accommodate both the healthy and tumour-bearing pancreata. To address these issues, we developed an improved stabilized window for intravital imaging of the pancreas (SWIP), which can be applied to not only the healthy pancreas but also to solid tumours like PDAC. Here, we validate the SWIP and use it to visualize a variety of processes for the first time, including (1) single-cell dynamics within the healthy pancreas, (2) transformation from healthy pancreas to acute pancreatitis induced by cerulein, and (3) the physiology of PDAC in both autochthonous and orthotopically injected models. SWIP can not only improve the imaging stability but also expand the application of IVI in both benign and malignant pancreas diseases.

Measuring depth of invasion of submucosa - invasive adenocarcinoma in oesophageal endoscopic specimens: how good are we?

AIMS: Emerging data support that submucosa-invasive (pT1b) esophageal adenocarcinomas are cured via endoscopic resection, provided that invasion measures ≤500 µm, they lack other histological features predictive of nodal metastasis and have negative margins. Hence, pathologists' measurement of the depth of submucosal invasion in endoscopic resections may dictate further management (i.e. endoscopic follow-up versus oesophagectomy). In this study, we assessed the interobserver agreement in measuring the depth of submucosal invasion in oesophageal endoscopic resections. METHODS AND RESULTS: Six subspecialised gastrointestinal (GI) pathologists from five academic centres independently measured the depth of submucosal invasion in µm from the deepest muscularis mucosae on 37 oesophageal endoscopic resection slides (round 1 scoring). A consensus meeting with a systematic approach for measuring and discussion of pitfalls was undertaken and remeasuring (round 2 scoring) was conducted. Interobserver agreement was assessed by the intraclass correlation coefficient (ICC) and Cohen's kappa statistics. A lack of agreement was seen among the six reviewers with a poor ICC for both rounds: 1 [0.40, 95% confidence interval (CI) = 0.26-0.56] and 2 (0.49, 95% CI = 0.34-0.63). When measurements were categorised as < or >500 µm, the overall agreement among the six reviewers was only fair for both rounds: 1 (kappa = 0.37, 95% CI = 0.22-0.53) and 2 (kappa = 0.29, 95% CI = 0.12-0.46). CONCLUSIONS: Our study shows a lack of agreement among gastrointestinal pathologists in measuring the depth of submucosal invasion in oesophageal endoscopic resections despite formulating a consensus approach for scoring. If important management decisions continue to be based upon this parameter, more reproducible and concrete guidelines are needed.

Clinical significance of pathologic abnormalities in biopsy samples from the appendiceal orifice.

AIMS: Appendiceal orifice mucosa often appears inflamed endoscopically, even when other colonic segments appear normal. Histological findings in biopsy samples taken from endoscopically abnormal mucosa may simulate a variety of inflammatory colitides. We performed this study to evaluate the clinical implications of inflammatory changes isolated to the appendiceal orifice. METHODS AND RESULTS: In this double cohort study, biopsy samples from 26 histologically abnormal appendiceal orifices were reviewed. Twenty-five control cases were culled from endoscopically normal (n = 11) and abnormal (n = 14) appendiceal orifices that were histologically normal. Histological findings were correlated with presentation, medication history, findings at other colonic sites and clinical outcomes. Study cases displayed active inflammation (n = 12), chronic active inflammation (n = 13) or features simulating collagenous colitis (n = 1). Eighteen patients had biopsies taken from other colonic sites; these revealed benign polyps (n = 10) or displayed active (n = 4) or chronic active (n = 4) inflammation. All patients with findings isolated to the appendiceal orifice were asymptomatic at most recent clinical follow-up. Four of eight (50%) of the patients with inflammation in other biopsy samples were ultimately diagnosed with ulcerative colitis, in keeping with the well-established role of the appendix as a 'skip lesion' in that disorder. Control patients presented for screening colonoscopy (n = 19), iron deficiency anaemia (n = 3) or change in bowel habits (n = 3) and none reported gastrointestinal symptoms upon follow-up, regardless of the endoscopic appearance of the appendiceal orifice. CONCLUSION: Isolated inflammation of the appendiceal orifice mucosa should not be regarded as a feature of evolving inflammatory bowel disease or other types of chronic colitis.

Neuroendocrine Tumor of the Common Bile Duct Associated With von Hippel-Lindau Disease.

We report a case of a common bile duct neuroendocrine tumor discovered in a patient with von Hippel-Lindau disease to emphasize the importance of recognizing this unusual diagnosis. This case illustrates the importance of endoscopic evaluation and the potential diagnostic pitfalls which may impact its appropriate management: the anatomic proximity of more common von Hippel-Lindau disease-related tumors, pathologic evaluation, and staging. Therefore, awareness of this rare diagnosis is important for appropriate treatment.

Features That Aid Identification of Autoimmune Gastritis in a Background of Active Helicobacter pylori Infection.

CONTEXT.­: Helicobacter pylori-associated and autoimmune gastritis may coexist in a subset of patients who require treatment for both disorders. OBJECTIVE.­: To delineate findings that identify autoimmune gastritis in the background of H pylori infection. DESIGN.­: We examined cases of (1) patients with H pylori-associated gastritis who had successful eradication therapy and subsequent biopsies diagnostic of autoimmune gastritis and (2) H pylori-associated gastritis wherein pathologists noted features of autoimmune gastritis during original interpretation. Control patients underwent H pylori eradication but lacked evidence of autoimmune gastritis or H pylori infection after 10 years of follow-up. RESULTS.­: Eight subjects had H pylori-associated gastritis followed by H pylori-negative sampling that showed autoimmune gastritis. Review of original samples showed full-thickness inflammation of oxyntic mucosa in 8 of 8 and oxyntic gland loss in 7 of 8 cases. Enterochromaffin-like (ECL) cell hyperplasia, pyloric metaplasia, and intestinal metaplasia were present in 4 of 8 (80% of 5 tested cases), 4 of 8, and 3 of 8 cases, respectively. Features of autoimmune gastritis were noted at the time of their original H pylori diagnosis in 11 study subjects. Ten of 11 samples displayed full-thickness inflammation of oxyntic mucosa and/or partial loss of oxyntic glands, 8 of 11 had ECL cell hyperplasia (all tested cases), 6 of 11 showed pyloric metaplasia, and 4 of 11 harbored intestinal metaplasia. Except for full-thickness oxyntic mucosa inflammation, these features were absent in control cases. CONCLUSIONS.­: Full-thickness inflammation combined with oxyntic gland loss and ECL cell hyperplasia may help to identify autoimmune gastritis in patients with concomitant H pylori infection.

Infectious diseases of the upper gastrointestinal tract.

A broad spectrum of pathogens produce gastrointestinal disease. The ongoing spread of human immunodeficiency virus/acquired immune deficiency syndrome, the increased use of immunosuppressive therapy and the persistence of overcrowding and suboptimal sanitation in underdeveloped areas facilitate both disease transmission from environmental and foodborne sources and person-to-person transmission. Clinicians increasingly rely on endoscopic biopsy sample interpretation to diagnose gastrointestinal infections. Thus, pathologists must be aware of diagnostic features of a variety of microbial pathogens. Detection with molecular techniques also allows for correlation between infectious agents and their histopathological features, which has expanded our knowledge of the inflammatory changes produced by infectious agents. This review covers infectious disorders of the upper gastrointestinal tract encountered in surgical pathology. Clinical, endoscopic and pathological features are presented. The review emphasises morphological features of viruses, bacteria, fungi and parasites that may be found in tissue samples, and the inflammatory patterns that they produce. Differential diagnoses and useful ancillary techniques are discussed.

Reproducibility of AJCC Criteria for Classifying Deeply Invasive Colon Cancers Is Suboptimal for Consistent Cancer Staging.

The eighth edition of the American Joint Committee on Cancer (AJCC) Staging Manual attempts to address ambiguity in the pT category assignment for colon cancer from prior editions. Despite modifications, the distinction between the pT3 and pT4a categories continues to be a source of diagnostic confusion. In this study, we assessed interobserver agreement among pathologists from different institutions in the application of AJCC eighth edition criteria for categorizing deeply invasive colonic adenocarcinomas. We identified morphologic patterns that produce diagnostic confusion. We assessed 47 colon cancers that closely approached the serosal surface. Six pathologists with interest in gastrointestinal pathology and 4 focused in other subspecialties classified each case as pT3 or pT4a, based on examination of low-magnification and high-magnification images of the most deeply invasive area. Interobserver agreement was assessed using Fleiss' κ. Cases displayed 3 morphologic patterns at the advancing tumor edge, namely, (1) continuous invasion through an inflammatory focus, (2) pushing border, and (3) infiltrative glands and cell clusters with serosal reaction. Gastrointestinal pathologists achieved slight (κ=0.21) or moderate (κ=0.46) and (κ=0.51) agreement in each category, whereas agreement among nongastrointestinal pathologist was fair (0.31) and (0.39), or moderate (0.57) for each category, respectively. In 10 (21%) cases, the distinction between pT3 and pT4a would have changed the overall clinical stage. We conclude that histologic criteria for serosal penetration is a persistent source of diagnostic ambiguity for gastrointestinal and general pathologists in the pT categorization of colon cancers. Clarification of these criteria will help ensure uniform reporting of pathologic and clinical stage.

Features of endoscopic procedure site reaction associated with a recently approved submucosal lifting agent.

Endoscopic resection techniques, such as endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), are frequently aided by injection of submucosal lifting solutions that create a plane for dissection and protect deeper mural layers. ORISE™ gel is a recently approved synthetic lifting solution that produces a localized inflammatory reaction associated with retained gel at the injection site. We describe a series of six cases of ORISE™-associated inflammatory lesions in patients who underwent endoscopic resections. Deposits comprised pale fibrillary or hyalinized eosinophilic material, depending on their age. All cases were associated with an inflammatory reaction composed of foreign-body giant cells and scattered eosinophils. ORISE™ gel extended laterally and deeply beyond residual tumors in all cases. Histochemically, the material proved to be negative for Congo Red, and mucicarmine, faint blue with Alcian blue, but positive for PAS and PAS-D. It stained blue with trichrome. Such deposits were absent in cases, wherein other widely-available lifting solutions were used. We compared ORISE™ deposits to histologically similar extracellular deposits, namely amyloid and pulse granulomata. Unlike ORISE™ material, amyloid deposits appear as waxy, more densely eosinophilic material, and stain positive with Congo Red. Amyloid demonstrated prominent intramucosal and perivascular distributions, features not seen in this series of ORISE™ deposits. Hyalinized pulse granulomata showed strong overlap with ORISE™ deposits, since they also comprise eosinophilic material associated with giant cell reaction. On the other hand, they form ribbons of glassy material in circumscribed lobules, unlike the ill-defined ORISE™ deposits. In summary, we describe the pathologic findings at injection sites in patients who underwent endoscopic procedures aided by the recently approved lifting agent, ORISE™. Pathologists should be aware of its appearance and associated reaction to avoid confusion with other common extracellular deposits seen in the gastrointestinal tract.

Smooth muscle tumors of the gastrointestinal tract: an analysis of prognostic features in 407 cases.

Smooth muscle tumors represent the second most common mural mesenchymal neoplasm in the gastrointestinal tract, but established criteria for prognostic assessment of these tumors are lacking. A large cohort of surgically resected intramural gastrointestinal smooth muscle tumors from 31 institutions was analyzed to identify potential prognostic features. Pathologic features were assessed by expert gastrointestinal and/or soft tissue pathologists at each center. Immunohistochemical confirmation was required. A total of 407 cases from the esophagus (n = 97, 24%), stomach (n = 180, 44%), small bowel (n = 74, 18%), and colorectum (n = 56, 14%) were identified. Patients ranged in age from 19 to 92 years (mean 55 years), with a slight female predominance (57%). Mean tumor size was 5.4 cm, with the largest tumor measuring 29 cm. Disease progression following surgery, defined as local recurrence, metastasis, or disease-related death, occurred in 56 patients (14%). Colorectal tumors were most likely to progress, followed by small bowel and gastric tumors. None of the esophageal tumors in this series progressed. Receiver operator characteristic analysis identified optimal cutoffs of 9.8 cm and 3 mitoses/5 mm2 for discriminating between progressive and non-progressive tumors. Histologic features strongly associated with progression by univariate analysis included moderate-to-severe atypia, high cellularity, abnormal differentiation (defined as differentiation not closely resembling that of normal smooth muscle), tumor necrosis, mucosal ulceration, lamina propria involvement, and serosal involvement (P < 0.0001 for all features). Age, sex, and margin status were not significantly associated with progression (P = 0.23, 0.82, and 0.07, respectively). A risk assessment table was created based on tumor site, size, and mitotic count, and Kaplan-Meier plots of progression-free survival for each subgroup revealed progression-based tiers. Based on our findings, it appears that nonesophageal gastrointestinal smooth muscle tumors measuring >10 cm and/or showing ≥3 mitoses/5 mm2 may behave aggressively, and therefore close clinical follow-up is recommended in these cases.

Cystic Lesions of the Pancreas: Differential Diagnosis and Cytologic-Histologic Correlation.

CONTEXT.­: Pancreatic cystic lesions (PCLs) are very common, and their detection is increasing with the advances in imaging techniques. Because of the major implications for management, distinguishing between neoplastic and nonneoplastic PCLs is critical. Neoplastic cysts with potential to progress into cancer include mucinous PCLs (intraductal papillary mucinous neoplasms and mucinous cystic neoplasms) and nonmucinous cysts (solid pseudopapillary tumors, serous cystic neoplasms, and neuroendocrine tumors with cystic degeneration). Nonneoplastic cysts with no risk of malignant transformation include pseudocysts, retention cysts, lymphoepithelial cysts, cystic pancreatic lymphangioma, and duplication cyst/ciliated foregut cysts. The role of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) cytology with cyst fluid analysis in the diagnosis of PCLs has evolved during the last decade; however, a definitive diagnosis on cytologic specimens is hampered by the sparse cellularity and can be challenging. EUS-FNA can play an important role to differentiate low-risk from high-risk pancreatic cysts and to distinguish between patients with cysts who need clinical follow-up versus those who require surgery. OBJECTIVE.­: To provide an integrative approach to diagnose pancreatic cystic lesions using EUS-FNA cytology and cyst fluid analysis, along with clinical, radiologic, histologic, genetic, and molecular characteristics. DATA SOURCES.­: The review and analysis of the latest literature describing pancreatic cystic lesions. CONCLUSIONS.­: Accurate diagnosis of PCLs requires a multidisciplinary and multimodal team approach, including the integration of clinical findings, imaging, cytology, cyst fluid analysis, and molecular testing.

Educational Case: Ischemic Disorders of the Gut in Adult Patients.

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040. 1.

Systematic Selective Sampling of Cholecystectomy Specimens Is Adequate to Detect Incidental Gallbladder Adenocarcinoma.

Many gallbladder adenocarcinomas (ACs) are detected incidentally in routine cholecystectomy specimens, yet sampling practices vary when intestinal metaplasia (IM) or dysplasia are found via routine sampling. Our practice has been to submit 5 additional sections when IM is found, but cases with dysplasia are entirely submitted. We sought to determine an appropriate sampling protocol when encountering these findings. We retrospectively identified cholecystectomy specimens with these features over a 26-month period, yielding 48 of 4059 (1%) cases. Four pathologists independently classified the (2 longitudinal and 1 cystic duct margin) original sections into 1 of 3 categories (IM, low-grade dysplasia [LGD] or high-grade dysplasia [HGD]); initial findings were correlated with final diagnoses. Sixteen (33%) cases had additional findings upon further sampling, including LGD (n=10) or HGD (n=4) and AC (n=2). HGD always accompanied malignancy. We prospectively analyzed 39 of 3133 (1%) additional cholecystectomy specimens, initially submitting the same routine sections. We submitted 5 random sections from cases with IM. Cases with LGD were first examined with 1 additional section per centimeter. All remaining tissue was submitted in all of these cases and separately reviewed. Cases with HGD were entirely submitted as both test cases with HGD in initial sections ultimately showed carcinoma. This protocol detected all cases of HGD and AC. Patients with clear cystic duct margins did not experience neoplastic progression, even if dysplasia was present elsewhere. We conclude gallbladders with HGD should be entirely submitted, LGD may be representatively sampled, and routine sampling is adequate for IM.