Cost benefit analysis and pathology review of ileostomy and colostomy specimens processed over a 20-year period.

Rising healthcare costs have been linked to overtreatment and overuse of available resources. Identifying and eliminating low-value services is vital for reducing such costs. At many institutions, including ours, all ileostomy and colostomy specimens are sent for pathological evaluation. It is estimated that approximately 120,000 ileostomy/colostomy procedures are done every year, and at least 1 million patients have stomas at any given time in North America. Hence, we decided to analyze the pathological findings and cost-benefit of undertaking the pathological evaluation of these colostomy and ileostomy specimens. The pathology database of our department was searched for all ileostomy and colostomy specimens received between 2000 and 2020, resulting in a total of 2762 cases (1944 ileostomy and 818 colostomy). We performed a cost-benefit analysis and pathologic review of these cases. The results of our study show that 99.38% of these specimens did not show any significant pathological abnormality, and non-neoplastic pathologic findings accounted for 99.63% of cases. Less than 1% of our cases showed any clinically significant pathological findings. All 10 cases that showed a neoplastic or malignant diagnosis showed some abnormal finding that was appreciated at the time of gross examination. We conclude that microscopic evaluation of ileostomy and colostomy specimens incurs significant costs and provides no clear value or relevant information for patient care. The results of our study provide support for ileostomy and colostomy specimens to be triaged by gross-only pathological examination in the first instance for the vast majority of cases.

Performance of Endoscopic Ultrasound-Guided Versus Percutaneous Liver Biopsy in Diagnosing Stage 3-4 Fibrosis.

BACKGROUND: Percutaneous liver biopsy (P-bx) is the gold standard for diagnosing advanced fibrosis. Despite the proven technical feasibility of EUS-guided liver bx (EUS-bx) as a novel alternative way of liver biopsy, the clinical applicability remains to be determined. AIMS: The primary aim of this study is to evaluate if EUS-bx, compared to P-bx, can effectively and safely obtain adequate specimen and accurately predict hepatic fibrosis. METHODS: This is a single center, retrospective chart review among patients with liver diseases at a tertiary endoscopy center from February 2011 to March 2020. We assessed the EUS-bx versus P-bx outcomes by success rate, performance, and safety profile. The primary outcome was the association between EUS-bx clinical variables and the presence of histologic liver fibrosis stage ≥ 3. The secondary outcomes were the associations between EUS-bx and variables indicative of fibrosis. RESULTS: Fifty-nine patients underwent EUS-bx; and 59, P-bx. All EUS-bx procedures were successfully completed. All 56/56 (100%) of EUS-bx vs. 50/52 (96.2%) P-bx were considered adequate samples. Tissue lengths were significantly longer in the EUS-bx cohort (p < 0.0001) with a trend towards a greater number of portal tracts. 46/56 (82.1%) cases of EUS-bx vs. 32/52 (61.5%) of P-bx had > 10 portal tracts; 21/56 (37.5%) cases of EUS-bx vs. 14/52 (26.9%) of P-bx had > 15 portal tracts. There were 6 (10.2%) EUS-bx vs. 1 (1.7%) P-bx related complication leading to a phone call (p = 0.061). CONCLUSIONS: EUS-bx can safely performed and accurately predict liver fibrosis stage as the standard P-bx without being influenced by procedure-related factors.

Atypical Presentations of Collagenous Gastritis Mimicking Celiac Sprue.

Collagenous gastritis has been reported as a rare cause of nausea, diarrhea, weight changes, and early satiety in female patients. Here, we describe two women aged 43 and 71 years who presented with similar symptoms. Gastric biopsies from both individuals showed thickened, irregular subepithelial collagen bands (>10 µm). The pathogenesis of collagenous gastritis is poorly understood, but it may be the presenting symptom for many underlying autoimmune conditions. In particular, there is a well-established connection between collagenous disorders of the gastrointestinal tract and celiac sprue, Sjögren syndrome, and lymphocytic colitis; however, none of these conditions had been diagnosed in our patients. The older woman had incidentally discovered hypogammaglobinemia and IgA deficiency, whereas the younger woman suffered from fibromyalgia. Although a gluten-free diet and budesonide have been effective in some cases, there is no standardized therapy for collagenous gastritis. Our patients trialed diet modification and have required no additional medical interventions.

Gallbladder carcinomas: review and updates on morphology, immunohistochemistry, and staging.

Gallbladder is a common surgical pathology specimen. However, carcinomas of the gallbladder are relatively rare in most western countries. Hence, general surgical pathologists may not be that familiar and comfortable diagnosing these tumors. In this review, we discuss the morphological and immunohistochemical characteristics of gallbladder carcinomas, provide updates on tumor classification and staging of these tumors as per the most recent WHO classification, and focus on practical considerations that would be most relevant to diagnosis and clinical management of these tumors.

Establishment and Characterization of a New Human Intrahepatic Cholangiocarcinoma Cell Line LIV27.

Cholangiocarcinoma (CCA) is a highly lethal cancer arising from the biliary tract epithelium. The cancer biology of this neoplasm is not well understood. To date, only a few CCA cell lines have been reported, which were mostly developed from Asian patients. In this study, we report and characterize a new intrahepatic CCA cell line, LIV27, derived from a surgically resected tumor in a 67-year-old Caucasian woman with primary sclerosing cholangitis (PSC). LIV27 cells grow well in collagen-coated flasks or plates with a doubling time of 57.8 h at passage 14. LIV27 cells have high tumorigenicity in nude mice and stain positive for CK7 and CK19, markers that differentiate CCA from hepatocellular carcinoma. Karyotype analysis showed that LIV27 is aneuploid. We established a single-locus short tandem repeat profile for the LIV27 cell line. This newly established cell line will be a useful model for studying the molecular pathogenesis of, and developing novel therapies for, cholangiocarcinoma.

Endoscopic Ultrasound-Guided Porto-systemic Pressure Gradient Measurement Correlates with Histological Hepatic Fibrosis.

BACKGROUND AND AIMS: Endoscopic ultrasound is a novel diagnostic approach to chronic liver diseases (CLDs), and EUS-guided porto-systemic pressure gradient measurement (EUS-PPG) is an important expansion with a well-developed technique. However, the clinical value and applicability of EUS-PPG measurement in predicting histologically advanced hepatic fibrosis remain unknown. METHODS: This was a single-center retrospective study on patients with various CLDs undergoing EUS-PPG and EUS-guided liver biopsy (EUS-bx) to assess if EUS-PPG measurements correlate with histological fibrosis stage and various surrogate markers for severity of CLDs and its safety. Cases with EUS-PPG were identified at the University of California Irvine, a tertiary endoscopy center, between January 2014 and March 2020. RESULTS: In 64 patients, the mean age was 57.5; 40 (62.5%), males; mean Child-Turcotte-Pugh (CTP) and Model for End-Stage Liver Disease (MELD) scores, 5.9 and 10.4, respectively. The procedure success rate was 100%. Twenty-nine (45.3%) had EUS-PPG ≥ 5 mmHg that was associated with clinical cirrhosis (p < 0.0001), clinical portal hypertension (p = 0.002), hepatic decompensation (p = 0.013), MELD-Na > 10 (p = 0.036), PLTs ≤ 120 × 109/L (p = 0.001), INR ≥ 1.05 (p = 0.007), presence of EV, GV, or PHG (p < 0.0001), biopsy-proven fibrosis stage ≥ 3 (p = 0.002), APRI > 2 (p = 0.001), and FIB-4 > 3.25 (p = 0.001). Multivariable analysis confirmed that EUS-PPG ≥ 5 mmHg was significantly associated with liver biopsy-proven fibrosis stage ≥ 3 (LR 27.0, 95% CI = 1.653-360.597, p = 0.004), independent of C-cirrhosis, C-PHTN, thrombocytopenia, splenomegaly, and APRI score > 2, and FIB-4 score > 3.25. There were no serious complications related to EUS-PPG procedures. CONCLUSIONS: EUS-PPG measurements provide excellent correlation with histological hepatic fibrosis stage and various clinical, laboratory, endoscopic and imaging variables indicative of advanced liver disease without serious adverse events.

A limited panel of INSM1 and LEF1 immunostains accurately distinguishes between pancreatic neuroendocrine tumor and solid pseudopapillary neoplasm.

Solid pseudopapillary neoplasm (SPN) and well differentiated pancreatic neuroendocrine tumor (PNET) can show significant cytomorphological overlap. In this study, we evaluated the role of INSM1 and LEF1 immunohistochemical stains in distinguishing between these two tumors. 22 SPN and 25 PNET surgically resected cases were stained for both INSM1 and LEF1. All the 22 cases of SPN showed strong and diffuse nuclear staining for LEF1 (in >95 % of tumor cells), while all 25 PNET were negative for LEF1. All 25 PNET cases were positive for INSM1 (moderate to strong intensity nuclear staining in >50 % of the tumor cells), while all 22 cases of SPN were negative for INSM1. The results of our study show that a limited panel comprising of INSM1 and LEF1 immunostains accurately distinguishes between SPN and PNET.

Comparison of Two Specialized Histology Needles for Endoscopic Ultrasound (EUS)-Guided Liver Biopsy: A Pilot Study.

BACKGROUND: EUS-guided liver biopsy (EUS-LB) has been shown to be a safe and effective alternative to percutaneous liver biopsy. The optimal needle device and technique for EUS-LB is still evolving. The aim of this study was to compare the efficacy of two second-generation 19G fine-needle biopsy (FNB) (Franseen- and Fork-tip) devices for EUS-LB. METHODS: This is a repeated-measure crossover study with a prospectively maintained cohort of patients. We performed EUS-LB with a one-pass and single-actuation method using two 19G FNB needles in 22 consecutive patients between 10/2018 and 9/2019. Patients were randomized to left vs right liver lobes to be biopsied as well as the needle sequence. The specimens obtained were evaluated for adequacy for histologic diagnosis. The primary outcome was number of complete portal tracts (CPTs), post-fix aggregate, and longest specimen length. Secondary outcomes were prefix aggregate specimen length and the specimen adequacy judged by two expert pathologists. RESULTS: A total of 44 liver biopsies were performed in 22 patients. The CPTs were higher in the Franseen-tip needle group compared to the Fork-tip needle group (14.4 vs 9.5, p = 0.043). Post-fix aggregate specimen length (44.9 mm vs 34.6 mm, p = 0.097), the post-fix longest specimen length (19.9 mm vs 13.7 mm, p = 0.175), and prefix aggregate specimen length (51.7 mm vs 45 mm, p = 0.265) were not significantly different. Both needles showed similarly high histologic adequacy (100% vs 95.5%, p = 0.312). Interestingly, the right of the liver showed higher yield of CPTs with both needles (Franseen, 16.2 vs. 12.8, p = 0.003, the Fork-tip, 12.8 vs. 7.0, p < 0.0001). CONCLUSION: EUS-guided liver biopsy using the 19G Franseen-tip needle may provide more CPTs than 19G Fork-tip needle on a single-pass, single-actuation comparison.

Incidence and significance of GATA3 positivity in gallbladder adenocarcinoma.

GATA3 immunostaining is a sensitive marker for mammary and urothelial carcinomas. It is routinely used in surgical pathology during workup of carcinomas of unknown origin. To the best of our knowledge, this is the first focused study of GATA3 expression in gallbladder adenocarcinomas. In this study, we evaluated GATA3 expression in 38 gallbladder adenocarcinomas. Eight of 38 (21%) gallbladder adenocarcinomas were positive for GATA3. The expression of GATA3 tended to be moderate to strong when present. It was patchy (<50% positivity) in 4 cases, characterized by discrete clusters or groups of malignant cells with areas of intervening negative tumor cells, whereas it was diffuse (>50% positivity) in the other 4 cases. GATA3 expression did not show any significant correlation with clinicopathologic features such as sex, histologic grade, perineural invasion, vascular invasion, pathologic stage, or distance metastasis. The results of our study show that a subset of gallbladder adenocarcinomas (21%) can be GATA3 positive. Awareness of this phenomenon is important while working up GATA3-positive carcinomas immunohistochemically.

Hepatocellular carcinomas can be Special AT-rich sequence-binding protein 2 positive: an important diagnostic pitfall.

Special AT-rich sequence-binding protein 2 (SATB2) is a sensitive and specific marker for tumors originating with the colon and appendix. It is now commonly used in surgical pathology, while working up carcinomas of unknown primary. We had anecdotally encountered occasional hepatocellular carcinomas (HCCs) that were SATB2 positive. Immunohistochemical expression of SATB2 in HCC has not yet been examined in detail. In this study, we evaluated SATB2 expression in 46 HCCs. Nineteen (41%) of 46 HCCs were positive for SATB2. SATB2 expression in HCCs was more commonly seen in poorly differentiated tumors (11 of 13 cases, 85%) than well and moderately differentiated tumors (8 of 33 cases, 24%), p value = 0.0001. No other statistically significant correlations were observed (p > 0.05). There were no other statistically significant correlations between SATB2 expression and age, gender, background liver disease, and cirrhosis (p > 0.05). Results of our study show that a significant subset (41%) of HCCs can be SATB2 positive. Awareness of this phenomenon is important as SATB2 expression in a liver tumor does not completely exclude a diagnosis of HCC.

Aberrant keratin expression is common in primary hepatic malignant vascular tumors: A potential diagnostic pitfall.

Malignant vascular neoplasms such as epithelioid hemangioendothelioma (EHE) and angiosarcoma (AS) can arise within the liver. The aim of this study was to study the expression of keratins CK7, AE1/AE3 and OSCAR in primary hepatic EHE and AS. 9 cases of hepatic EHE and 13 cases of hepatic AS were stained with ERG, CK7, keratin AE1/AE3 and keratin OSCAR. Their expression was graded as 1+ (1-25% of tumor cells positive), 2+ (26-50%), 3+ (51-75%) or 4+ (>75%). ERG was positive in all 9 (100%) EHEs and all 13 (100%) ASs. CK7 was positive in 5/9 (56%) EHEs (2, 1+; 1, 2+; 1, 3+; 1, 4+) and 1/13 (8%) AS (2+). Keratin OSCAR was positive in 6/9 (67%) EHEs (5, 1+; 1, 2+) and 4/13 (31%) ASs (2, 1+; 1, 2+; 1, 4+). Keratin AE1/AE3 was positive in 6/9 (67%) EHEs (3, 1+; 3; 2+) and 4/13 (31%) ASs (2, 1+; 1, 2+; 1, 4+). Overall, 6/ 9 (67%) EHEs were positive for at least one keratin marker, of which 5 were positive for all 3 keratins (AE1/AE3, OSCAR and CK7) while 1 was positive only for 2 keratins (OSCAR and AE1/AE3). 4/13 (31%) of ASs were positive for both keratins OSCAR and AE1/AE3, of which 1 case was also positive for CK7. Aberrant keratin expression is common in primary hepatic EHEs (67%) and ASs (31%). Awareness of this diagnostic pitfall is important for avoiding misdiagnosis of these primary hepatic malignant vascular tumors as carcinomas.

Diffuse Adenomatosis and Hepatocellular Carcinoma Treated with Liver Transplantation in an Adolescent Female with Kabuki Syndrome with a Novel KMT2D Gene Mutation.

Kabuki syndrome (KS) is a rare disorder primarily associated with mutations in the KMT2D and KDM6A genes. Several tumors have been reported with KS; however, there have been no reports of hepatocellular carcinoma (HCC) or hepatic adenomatosis. We present an adolescent girl with KS and a novel KMT2D mutation who developed diffuse adenomatosis, HCC, and subsequently underwent liver transplantation.

Albumin In Situ Hybridization Can Be Positive in Adenocarcinomas and Other Tumors From Diverse Sites.

OBJECTIVES: Albumin messenger RNA (mRNA) expression is a marker of hepatocellular differentiation. Most published data are from review of tissue microarrays, and albumin in situ hybridization (ISH) expression across several tumor types is incompletely characterized. METHODS: Sections from 221 tumors were evaluated for albumin mRNA. Immunohistochemistry was used to confirm diagnoses. Albumin ISH was performed according to manufacturer-provided instructions. Fifty-nine cases were evaluated with both commercial ISH assays. RESULTS: Albumin mRNA was detected in all hepatocellular carcinomas (HCCs) and 81% of intrahepatic cholangiocarcinomas. Lung (20%), gallbladder (39%), hepatoid pancreatic (n = 1 of 1) adenocarcinoma, breast invasive ductal carcinoma (18%), yolk sac tumor (25%), and acinar cell carcinoma (29%) showed expression. Both assays were concordant in 93% of cases. CONCLUSIONS: Albumin ISH was expressed in all HCCs studied. It was also positive in intrahepatic cholangiocarcinoma and patchy positive in gallbladder adenocarcinoma and a subset of other neoplasms, which can be a potential pitfall.

Colonic Adenomatous Polyps Involving Submucosal Lymphoglandular Complexes: A Diagnostic Pitfall.

Lymphoglandular complexes (LGCs) are lymphoid nodules containing intestinal mucosa, present in close apposition to muscularis mucosae or submucosa. Rarely, colorectal adenomas involve submucosal LGCs, simulating invasive adenocarcinoma with associated submucosal lymphoid aggregates, and presenting a diagnostic pitfall. We aimed to identify distinctive histologic features between submucosal LGCs and true invasion. Seven adenomas (tubular/tubulovillous adenomas [n=6], including 4 with high-grade dysplasia and 1 with focal intramucosal adenocarcinoma, and sessile serrated adenoma [n=1]) were in the right (n=5) and left colon (n=2). Seven adenocarcinomas were in the right (n=3), left (n=2), and rectum/rectosigmoid colon (n=2). Adenomatous glands involving submucosal LGCs were invested in lamina propria, showed continuity with surface adenoma, were well rounded and contained within lymphoid tissue, and predominantly lacked classic features of "pseudoinvasion." One case showed a herniation pattern carrying muscularis mucosae. Adenocarcinomas had at least one of the following features: infiltrating single cells/small clusters (n=5), poorly formed, fused, and irregular glands (n=2), solid tumor nests (n=1), desmoplastic reaction (n=5), intraluminal necrosis (n=3), or lymphovascular invasion (n=1). In contrast, no adenoma had these features. Adenocarcinomas showed no herniation, but connection to surface tumor (n=5) was seen. Five invasive adenocarcinomas extended into the submucosa beyond the lymphoid aggregate. In conclusion, adenomas involving LGCs are a rare, clinicopathologically distinct form of pseudoinvasion that mimics invasive adenocarcinoma; histologic features that distinguish them are a well-rounded contour contained within the lymphoid tissue, and lack of infiltrating single cells/small clusters, poorly formed, fused, and irregular glands, solid tumor nests, desmoplastic reaction, and lymphovascular invasion.

Copper deposition in focal nodular hyperplasia and inflammatory hepatocellular adenoma.

AIMS: To examine copper deposition in focal nodular hyperplasia (FNH) and inflammatory hepatocellular adenoma (IHA) and to determine if it can play a role in their differentiation. METHODS: 28 FNHs and 19 IHAs from surgical resections showing typical morphological and immunohistochemical features were stained with rhodanine to evaluate for copper deposition. Histological features such as nodularity, fibrous bands, ductular proliferation, steatosis, ballooned hepatocytes and lymphocytic inflammation were also scored. RESULTS: Copper deposition was detected in 96% (27/28) of FNHs and 37% (7/19) of IHAs, P<0.001. In all cases, copper was seen within the hepatocytes only around the pseudo-portal tracts or areas of fibrosis. Copper deposition in IHA was significantly associated with presence of lymphocytic inflammation (P=0.04) but not associated with features like nodularity, fibrous bands, ductular proliferation, ballooned hepatocytes and steatosis (P>0.05, for all). In FNH, the presence and degree of copper deposition was not significantly associated with any histological features (P>0.05, for all). CONCLUSIONS: Copper deposition occurs more frequently in FNH (96%) than IHA (37%), P<0.001. However, the presence of copper alone cannot be used as a feature to differentiate between FNH and IHA.

Hepatocyte Antigen Expression in Barrett Esophagus and Associated Neoplasia.

Hepatocyte antigen or hepatocyte paraffin 1 (Hep Par 1) is widely used as a diagnostic immunomarker for hepatocellular carcinoma. It has also been identified as a rate-limiting enzyme of the urea cycle, carbamoyl phosphate synthetase 1. Hep Par 1 has been detected in non-neoplastic small intestinal epithelium, but its expression in Barrett esophagus and its related neoplasia has not been well investigated. We immunohistochemically evaluated expression of Hep Par 1 on 75 cases of Barrett esophagus (25 cases without dysplasia, 16 cases with low-grade dysplasia, 25 cases with high-grade dysplasia, and 9 cases with intramucosal adenocarcinoma) on endoscopic biopsies and endoscopic mucosal resections. All 25 cases without dysplasia (100%) showed granular cytoplasmic Hep Par 1 staining (24 diffuse and 1 focal). Of the 16 cases with low-grade dysplasia, 12 (75%) were positive (5 diffuse and 7 focal), whereas 4 (25%) were negative (P=0.018). Of the 25 cases with high-grade dysplasia, 9 (36%) showed focal positivity, whereas 16 (64%) were negative (P=0.0001). Similarly of the 9 cases of intramucosal adenocarcinomas 3 (33%) were focally positive, whereas 6 (67%) were negative (P=0.0001). Hep Par 1 is diffusely expressed in non-neoplastic Barrett esophagus while it is frequently lost in related dysplasia and adenocarcinoma, suggesting decreased level of HepPar1 may represent an early event in Barrett-related tumor genesis. This warrants additional investigation to look for the possible role of carbamoyl phosphate synthetase 1 in the pathogenesis of Barrett-related neoplasia.

Squamoid morules in the pseudoinvasive foci of colonic polyp morphologically mimic invasive carcinoma.

Colorectal adenomas can show focal squamous differentiation or squamoid morules. We describe histologic findings of squamoid morules in the pseudoinvasive foci of colorectal polyps mimicking invasive carcinoma. Five colonic polyps with squamoid morules in the pseudoinvasive foci were collected. Histologic review and immunostains for cytokeratin 5/6, p63, synaptophysin, and chromogranin were performed on cases with squamoid morules. Forty-seven consecutive colorectal polyps with pseudoinvasion, none of which showed squamoid morules by histology review, and their clinicopathologic features were compared with the cases containing squamoid morules. Cases with squamoid morules more frequently occurred in younger patients (P=.047) and were located in right colon (P=.027) than those without squamoid morules. Diagnosis of the polyps included tubular/tubulovillous adenoma with low-grade (with squamoid morules, n=3; versus without squamoid morules, n=29) or high-grade dysplasia (n=2 versus n=15) and sessile serrated adenoma (none versus n=3). Squamoid morules formed nodules protruding into the lumen of glandular structures or partially replaced adenomatous glands without forming a discrete nodule. They also presented as solid nests showing a well-formed morular structure around the bottom of adenomatous glands or myxoinflammatory stroma. Importantly, squamoid morules often formed a pseudocribriform or solid nest sitting in the stroma of pseudoinvasive foci. All cases (n=4) showed cytokeratin 5/6 positivity and p63 negativity in squamoid morules. Three and 1 of 4 cases showed focal positivity for synaptophysin and chromogranin, respectively, in squamoid morules. Squamoid morules in colonic adenomatous polyps can mimic invasive carcinoma when present in the pseudoinvasive foci. Pathologists should be aware of their presence.