Ancillary Stains Research Articles

Sneaky DCIS-looking Invasive Ductal Carcinoma of the Breast in the Extensive DCIS Background

Abstract Introduction/Objective In the most cases, invasive ductal carcinoma (IDC) of the breast is identifiable when they present with classic infiltrative growth pattern. However, subset of IDC can occur in a very sneaky way, significantly mimicking the appearance of ductal carcinoma in situ (DCIS). In this condition, it’s much more easier to miss the invasive component without pulling ancillary staining when morphologic findings are extremely compatible with DCIS, especially the diagnosis of DCIS was made on the previous biopsy. Methods/Case Report Retrospective analysis of the histologic and immunohistochemical findings of pure DCIS and DCIS-looking invasive ductal carcinoma. Results (if a Case Study enter NA) Here, we reported a 55 year-old female who was noted to have microcalcification at the 11:00 o’clock of the right posterior breast on routine mammographic examination in 09/2023. Biopsy of the calcification area in 10/2023 reported high grade DCIS (ER+ PR-). Histologic examination of subsequent mastectomy specimen showed two separate DCIS-looking areas. Immunohistochemical (IHC) staining showed that myoepithelial markers, p63 and smooth muscle myosin heavy chain (SMMHC), were retained at the periphery of all the expanded acini in one area. Unexpectedly and surprisingly, p63 and SMMHC were completely lost at the periphery of part of the DCIS-looking acini in another area, immunohistochemically compatible with the diagnosis of invasive ductal carcinoma admixed with DCIS. Conclusion Knowing that invasive ductal carcinoma of the breast can present as DCIS-looking morphology, especially given the condition that the diagnosis of DCIS was rendered on the previous biopsy, will enhance awareness of pathologists to recognize sneaky DCIS-looking invasive ductal carcinoma in the extensive DCIS background. In turn, this will prevent misdiagnosis and under-treatment of patients with invasive ductal carcinoma of the breast.

Comparing Accuracy of Helicobacter pylori Identification Using Traditional Hematoxylin and Eosin-Stained Glass Slides With Digital Whole Slide Imaging

With advancements in the field of digital pathology, there has been a growing need to compare the diagnostic abilities of pathologists using digitized whole slide images against those when using traditional hematoxylin and eosin (H&E)-stained glass slides for primary diagnosis. One of the most common specimens received in pathology practices is an endoscopic gastric biopsy with a request to rule out Helicobacter pylori (H. pylori) infection. The current standard of care is the identification of the organisms on H&E-stained slides. Immunohistochemical or histochemical stains are used selectively. However, due to their small size (2-4 μm in length by 0.5-1 μm in width), visualization of the organisms can present a diagnostic challenge. The goal of the study was to compare the ability of pathologists to identify H. pylori on H&E slides using a digital platform against the gold standard of H&E glass slides using routine light microscopy. Diagnostic accuracy rates using glass slides vs digital slides were 81% vs 72% (P = .0142) based on H&E slides alone. When H. pylori immunohistochemical slides were provided, the diagnostic accuracy was significantly improved to comparable rates (96% glass vs 99% digital, P = 0.2199). Furthermore, differences in practice settings (academic/subspecialized vs community/general) and the duration of sign-out experience did not significantly impact the accuracy of detecting H. pylori on digital slides. We concluded that digital whole slide images, although amenable in different practice settings and teaching environments, does present some shortcomings in accuracy and precision, especially in certain circumstances and thus is not yet fully capable of completely replacing glass slide review for identification of H. pylori. We specifically recommend reviewing glass slides and/or performing ancillary stains, especially when there is a discrepancy between the degree of inflammation and the presence of microorganisms on digital images.

Métodos de diagnóstico convencionais e imunoistoquímica na detecção de espécies de Helicobacter gástricas em cães com gastropatia crônica

ABSTRACT An accurate diagnostic test for Helicobacter spp. infection in dogs is necessary but no gold standard diagnostic method has yet been established. The purpose of this study was to assess the sensitivity of conventional diagnostic methods as opposed to immunohistochemistry (IHC) in the detection of Helicobacter spp. in gastric samples of dogs with chronic gastropathy. Samples of gastric fundus, body and antrum were collected by gastroscopy from 13 domestic dogs presenting chronic vomit and submitted to the rapid urease test (RUT), cytopathology, histopathology with Hematoxylin-Eosin (HE) and Warthin-Starry (WS) stain, and IHC. Cohen's kappa coefficient was carried out to determine the agreement between techniques compared to IHC. Prevalence of colonization detected by IHC was 92% and was higher in the gastric fundus. The sensitivity of each technique in detecting Helicobacter spp. in the gastric fundus, body, and antrum, respectively, were as follows: RUT 50%, 70%, 17%; cytology 58%; 70%, 50%; HE 42%; 70%, 50%; WS 67%; 80%, 50%. We found that IHC was the most sensitive method for Helicobacter spp. diagnosis revealing that gastric fundus samples have higher presence of bacteria. Squash cytology enhances sensitivity and ancillary staining such as WS should be taken into consideration towards diagnosis.

S1998 Colonic Merkel Cell Carcinoma of Unknown Primary: Small Cell Carcinoma Outside the Usual

Introduction: Merkel cell carcinoma (MCC) is a rare neuroendocrine skin carcinoma with documented metastases to the liver, lungs, and gastrointestinal (GI) tract. Colonic metastases are rare but seen with recurrent or primary cutaneous lesions. Described is a patient who presented with bowel obstruction with a hepatic flexure MCC of unknown primary (MCCUP). Case Description/Methods: A 69-year-old female with a history of breast, lung, and anal cancer presented to the emergency department with abdominal pain and distension. Computed tomography of her abdomen demonstrated dilated loops of small bowel and a partial obstruction with transition point in the hepatic flexure. Colonoscopy demonstrated a 4 cm mass at the hepatic flexure obstructing the lumen. Biopsy revealed a high-grade neuroendocrine carcinoma. A right colectomy and histopathology confirmed small cell neuroendocrine carcinoma involving the colonic wall into the pericolic adipose tissue with nodal involvement. It was positive on cytokeratin CAM 5.2, synaptophysin, and Merkel cell polyomavirus (MCPvY) and negative on CDX-2 and TTF-1, excluding primary bowel or lung small cell carcinomas, respectively. Dermatologic evaluation did not reveal a primary cutaneous lesion. Genetic testing was unremarkable. Discussion: This is the first case of MCCUP presenting with colonic obstruction; prior described cases of MCC metastatic to the colon were recurrent disease or from primary skin lesions. Because MCC is rare, has non-specific symptoms, and may lack a primary lesion, MCCUP must be distinguished from other small round blue cell malignancies more commonly found in the GI tract. Thus, neuroendocrine, keratin and MCPyV ancillary staining are critical to distinguish MCC from B-cell lymphoma, small cell carcinoma of bowel or lung primary, and other metastatic dermal malignancies. MCPyV testing in the absence of prior diagnosis is uncommon but vital to the workup of neuroendocrine carcinomas when CDX-2 and TTF-1 are negative as MCPyV positive lymph nodes predict worse outcomes such as disease-free survival. In this patient immunosuppression and prior radiation increased the risk of MCC, and even suggest that this might be a colonic primary. Rarely, MCC and MCCUP are root causes of neuroendocrine carcinomas of the GI tract. In immunocompromised patients, biopsy and pathologic staining are necessary to distinguish insidious malignancies. MCPyV analysis is helpful for diagnosing MCCUP and informing its prognosis.

Nocardiosis diagnosed on bronchoalveolar lavage: Role of cytopathology.

Nocardia are gram-positive, filamentous bacteria that have the potential to cause serious disease, particularly in immunocompromised patients. Nocardia may cause a complex clinical picture, with radiologic features that can mimic other infectious organisms or malignancy. The organisms are not easily identified on cytologic examination given their weak staining with routine preparations and because they may be obscured by the associated inflammatory exudate. However, recognition of subtle features and a high index of suspicion in the appropriate clinical setting can lead to the appropriate triaging of material for ancillary stains and confirmatory microbiology tests. We herein present three cases of nocardiosis diagnosed on bronchoalveolar lavage in order to discuss the clinical presentation and cytomorphologic features with emphasis on the role of cytopathologists in facilitating timely diagnosis and helping direct appropriate management.

Empirical ordering of stains in cytology—are we saving or losing?

Bronchoalveolar lavage (BAL) and body cavity fluids (pleural and peritoneal) have a useful role in the detection of infectious diseases, especially when combined with ancillary stains (Grocott methenamine silver, acid-fast bacilli, Fite, and cytomegalovirus). However, empirical ordering of stains and duplicate testing by concurrent microbiology cultures leads to unnecessary wastage of resources. The aim of our study was to optimize the use of resources. We performed a retrospective review of all BALs and body cavity fluids from 2016 to 2018 to determine the baseline stain order rate, which was then used in conjunction with clinical information to create a reasonable target for 2019. The methods implemented included communication with the clinical team to modify current ordering practice, monitoring stain orders prospectively through 2019, and updating the cytology requisition form to limit upfront ordering of ancillary stains. From 2016 to 2018, of the 1270 specimens reviewed, 323 (55%) were BALs and 108 (16%) were body cavity fluids that had had ≥2 stains preordered. This was reduced by the end of 2019 to 10% of BALs and 3.4% of body cavity fluids, leading to $25,935.24 in costs savings (including 275 hours of technician time and 39.3 hours of pathologist time). We found that ancillary microorganism stains have limited utility in cytology specimens and should only be ordered when indicated after a review of the initial smears. In today's era of cost savings, upfront ordering of ancillary stains can lead to significant wastage of resources that can be prevented by improving workflow.

Cytologic Assessment of Cystic/Intraductal Lesions of the Pancreatobiliary Tract.

Because of new and improved imaging techniques, cystic/intraductal pancreatobiliary tract lesions are increasingly being discovered, and brushings or endoscopic ultrasound/computed tomography/magnetic resonance imaging-guided fine-needle aspiration biopsies from these lesions have become an integral part of pathologists' daily practice. Because patient management has become increasingly conservative, accurate preoperative diagnosis is critical. Cytologic distinction of low-risk (pseudocysts, serous cystadenoma, lymphoepithelial cysts, and squamoid cysts of the pancreatic duct) from high-risk pancreatic cysts (intraductal papillary mucinous neoplasm and mucinous cystic neoplasm) requires incorporation of clinical, radiologic, and cytologic findings, in conjunction with chemical and molecular analysis of cyst fluid. Cytopathologists must ensure appropriate specimen triage, along with cytologic interpretation, cyst classification, and even grading of some (mucinous) cysts. Epithelial atypia in mucinous cysts (intraductal papillary mucinous neoplasm and mucinous cystic neoplasm) has transitioned from a 3-tiered to a 2-tiered classification system, and intraductal oncocytic papillary neoplasms and intraductal tubulopapillary neoplasms have been separately reclassified because of their distinctive clinicopathologic characteristics. Because these lesions may be sampled on brushing or fine-needle aspiration biopsy, knowledge of their cytomorphology is critical. To use an integrated, multidisciplinary approach for the evaluation of cystic/intraductal pancreatobiliary tract lesions (incorporating clinical, radiologic, and cytologic findings with [chemical/molecular] cyst fluid analysis and ancillary stains) for definitive diagnosis and classification. Review of current literature on the cytopathology of cystic/intraductal pancreatobiliary tract lesions. Our knowledge/understanding of recent updates in cystic/intraductal pancreatobiliary lesions can ensure that cytopathologists appropriately triage specimens, judiciously use and interpret ancillary studies, and incorporate the studies into reporting.

Impact on colorectal cancer pathology reporting practice of migration from TNM 5 to TNM 8.

The introduction of TNM 8 into UK pathology practice in January 2018 considers tumour deposits in colorectal cancer staging for the first time. The impact of this new classification on pathology reporting practices has yet to be evaluated. A clinical audit was conducted, comparing consecutive colorectal cancer resection specimens reported under TNM 5 classification guidelines in 2017 (n=177) and TNM 8 guidelines in 2018 (n=234). Tumour features (venous invasion, perineural invasion, lymph node metastatic disease, tumour deposits) and changes in reporting practices were evaluated among four specialist gastrointestinal pathologists working within a large pathology department. Adoption of TNM 8 practice led to an approximate doubling in the use of ancillary stains (41.0% of TNM 8 versus 22.0% of TNM 5 cases, P<0.001) to help evaluate tumours. A narrowing of the range between pathologists was observed in reporting cases as having one or more form of regional, extramural, discontinuous tumour (TNM 5 range=50.0-79.0%, TNM 8 range=57.8-65.7%), with no change in the overall proportion of cases reported as such (62.7% versus 62.4%, P=0.95). However, significant interobserver variation in reporting rates for individual parameters remained. TNM 8 colorectal cancer staging offers potentially greater reproducibility in pathology reporting of regional, extramural, discontinuous disease with similar proportions of patients reported as having one or more of these forms of tumour spread compared with TNM 5. Further guidance in defining individual features is required to reduce interobserver variation in pathology assessments and to help elucidate the clinical significance of each parameter.

Lymphovascular invasion in early gastric cancer: impact of ancillary D2-40 and elastin staining on interobserver agreement.

Lymphatic invasion (LI) and venous invasion (VI) are the strongest risk factors for lymph node metastasis in patients with early gastric cancer, and may predict their prognosis. We aimed to investigate interobserver agreement among pathologists before and after adding ancillary staining for diagnosing LI and VI in this setting. This retrospective study included 100 specimens of submucosal invasive gastric cancer from 100 patients treated using endoscopic resection. Three pathologists (expert, intermediate and trainee experience levels) independently evaluated individual LI and VI status using haematoxylin and eosin (H&E)-stained slides, and re-evaluated their decisions by reviewing corresponding D2-40-stained and elastin-stained slides. Interobserver agreement was assessed using κ statistics. With the ancillary D2-40 staining, there was an improved agreement for LI diagnoses between the expert and intermediate pathologist (H&E κ=0.78, D2-40 κ=0.85) and between the expert and trainee pathologist (H&E κ=0.37, D2-40 κ=0.56). With the ancillary elastin staining, there was an improved agreement for VI diagnoses between the expert and intermediate pathologists (H&E κ=0.25, elastin κ=0.63) and between the expert and trainee pathologists (H&E κ=0.29, elastin κ=0.45). With both the ancillary D2-40 and elastin staining there was an improved interobserver agreement for LI and VI diagnoses, regardless of the pathologist's experience. This ancillary staining may be useful in improving the accuracy of LI and VI diagnoses, helping to improve the risk stratification of early gastric cancer patients.

Review: Diagnosis of Helicobacter pylori infection.

Endoscopic imaging of the stomach is improving. In addition to narrow band imaging, other methods, for example, blue light imaging and linked color imaging, are now available and can be combined with artificial intelligence systems to obtain information on the gastric mucosa and detect early gastric cancer. Immunohistochemistry is only recommended as an ancillary stain in case of chronic active gastritis without Helicobacter pylori detection by standard staining, and recommendations to exclude false negative H. pylori results have been made. Molecular methods using real-time PCR, droplet digital PCR, or amplification refractory mutation system PCR have shown a high accuracy, both for detecting H. pylori and for clarithromycin susceptibility testing, and can now be used in clinical practice for targeted therapy. The most reliable non-invasive test remains the 13 C-urea breath test. Large data sets show that DOB values are higher in women and that the cut-off for positivity could be decreased to 2.74 DOB. Stool antigen tests using monoclonal antibodies are widely used and may be a good alternative to UBT, particularly in countries with a high prevalence of H. pylori infection. Attempts to improve serology by looking at specific immunodominant antigens to distinguish current and past infection have been made. The interest of Gastropanel® which also tests pepsinogen levels was confirmed.

How I investigate bone marrow necrosis.

Hematopathologists encounter bone marrow biopsy specimens with marrow necrosis relatively infrequently; when necrosis is seen, determining the clinical significance can be challenging. While bone marrow necrosis is not uncommon in site-directed biopsy specimens or autopsy material, substantial necrosis is much less common in nondirected bone marrow biopsy specimens. Retrospective review showed the prevalence of bone marrow necrosis to vary between 0.3% and 2% antemortem, depending on the patient population. Numerous causes of bone marrow necrosis have been identified, including malignancy, radiation/chemotherapy, medication, infection, autoimmune disease, disseminated intravascular coagulation, antiphospholipid syndrome and other thrombotic disorders, granulocyte-colony stimulating factor (G-CSF) exposure, and hemoglobinopathies. Clinical findings associated with bone marrow necrosis include bone pain and fever, cytopenias, elevated LDH and ferritin, and leukoerythroblastosis. Rarely, such as in fat embolization syndrome (FES), bone marrow necrosis can be associated with thrombotic microangiopathy, neurologic dysfunction, and multiorgan failure. A thorough review of the patient's clinical record (including medical history, clinical presentation, and other laboratory findings), a thorough morphologic review of the bone marrow with appropriate ancillary stains, and an appreciation of the causes of bone marrow necrosis in different patient populations are required to determine the underlying cause of bone marrow necrosis. The purpose of this review is to present a strategy for evaluation of bone marrow necrosis found in an antemortem biopsy specimen.

Current Procedural Terminology Coding in an Academic Breast Pathology Service: An Illustration of the Undervaluation of Breast Pathology.

Many physicians share the perception that the work required to evaluate breast pathology specimens is undervalued by Current Procedural Terminology (CPT) codes. To examine this issue, we compared slide volumes from an equal number of breast and nonbreast specimens assigned 88305, 88307, or 88309 CPT codes during four 2.5-week periods over 1 year. For each specimen, a number of initial hematoxylin and eosin-stained sections (H&Es), preordered additional H&E sections (levels), H&E sections ordered after initial slide review (recuts), and specimen type were recorded. Slides associated with ancillary stains were not considered. In total, 911 breast and 911 nonbreast specimens, each assigned 88305 (n=580), 88307 (n=320), and 88309 (n=11) CPT codes, were compared. Breast 88305 specimens were mainly core biopsies and margins and generated 2.3 and 6.4 times the H&Es and recuts, respectively, than did nonbreast specimens (P<0.01). Breast 88307 specimens were mainly lymph nodes and lumpectomies and generated 1.8 times the total slides than did nonbreast specimens (P<0.01). Eleven modified radical mastectomies (88309) generated 2.1 times the total slides than nonbreast 88309 specimens (P<0.01). In total (n=911 in each cohort), breast specimens generated 1.9, 4.0, and 1.7 times the H&Es, recuts, and total slides (P<0.01) than did nonbreast specimens. At our academic institution, the slide volume for breast specimens is nearly twice that of similarly coded nonbreast specimens. These results have significant implications for workload management and assessing pathologist productivity, particularly in subspecialty practices.

Pseudo solid-appearing pancreatic serous microcystic adenomas: Histologic diagnosis with the EUS core biopsy fork-tip needle.

Background and Objectives:Despite rarely, serous cystic adenoma (SCA) can assume a pseudo-solid aspect mimicking other pancreatic neoplasm as neuroendocrine tumor. EUS-FNA cytology has low diagnostic accuracy due to the scant cellularity of the collected samples. Histological diagnosis is usually made after resection. Recently, end-cutting needles for EUS-fine-needle biopsy (EUS-FNB), which obtain tissue cores by penetrating the lesions, have been developed. We aimed to assess the capability of EUS-FNB with SharkCore™ needles in the preoperative diagnosis of serous cystic adenoma pseudo-solid-appearing on imaging (Sa-SCA).Materials and Methods:Between January 2016 and January 2018, data from consecutive adult patients, who were referred for EUS-FNB of a solid pancreatic lesion and were diagnosed with having SCA, were retrieved from a single-center institutional database.Results:Two patients were excluded because of microcystic aspect at EUS. Histological diagnosis of SCA was made by EUS-FNB in the remaining 7 patients (5 females; mean age of 62.5 years). Lesions (mean size of 19.8 mm) were hypervascular on cross-sectional imaging, slightly hyperdense magnetic resonance imaging with T2-weighted images can, and negative at 68Ga-somatostatin receptor positron emission tomography and 18fluoro-deoxyglucose positron emission tomography. EUS-FNB samples were judged adequate for a definitive diagnosis in all cases, achieving specimens suitable for histological evaluation and several ancillary stains. Histochemical positivity for periodic acid-Schiff (PAS) and PAS with diastase digestion was observed in 7/7 cases. Immunohistochemical positivity for α-inhibin (7/7), GLUT1 (6/6), MUC6 (5/5), and negativity for synaptophysin (7/7) and chromogranin A (2/2) favored SCA diagnosis.Conclusions:In the case of preoperative workup suspected for Sa-SCA, a “forward acquiring” needle could improve the rate of preoperative histological diagnosis.

Factors Associated With Detection of Helicobacter pylori in Gastric Biopsies: A Case-Control Study of 396 Biopsies.

Helicobacter pylori (HP) infection is associated with significant gastric mucosal inflammation. We aimed to determine the clinicopathologic features associated with HP in gastric biopsy. Three hundred ninety-six gastric biopsies were evaluated including 165 HP-positive cases and 231 randomly selected HP-negative controls. HP was detected using hematoxylin and eosin (H&E), Giemsa, and immunohistochemistry staining. The univariate and multivariate analyses were conducted to study the relationship of clinicopathologic characteristics and HP infection. Among the HP-positive cases, 131 cases were confirmed by H&E staining and 34 cases were confirmed by Giemsa or immunohistochemistry staining. Compared with chronic inactive gastritis, chronic active gastritis was more likely associated with having HP detected by H&E. Males were more likely to have HP gastritis than females (odds ratio: 1.72, P=0.01). The patients who had chronic active gastritis or chronic gastritis (moderate or severe) were more likely to have HP infection than patients with mild chronic gastritis (P<0.001). Conversely, patients who had intestinal metaplasia were less likely to have HP infection than patients without intestinal metaplasia (odds ratio: 0.22, P<0.001). However, concurrent atrophic gastritis was not related to HP infection (P=0.37). HP infection history was not associated with HP infection (P=0.74). HP detection in gastric biopsies is associated with active inflammation, male sex, and the lack of intestinal metaplasia, but not atrophic gastritis or HP infection history. Routine ancillary staining may not be required for HP detection in all biopsy specimens. We do not recommend ancillary staining for mild chronic inactive gastritis.

Warthin-Starry Staining for the Detection of Helicobacter pylori in Gastric Biopsies.

BackgroundWarthin-Starry (WS) staining is an ancillary stain used in the detection of Helicobacter sp., spirochaete and other microorganisms in tissue sections. The present study aimed to determine the validity of WS stain in the confirmation of H. pylori diagnosis in gastric biopsies in comparison with anti-H. pylori immunohistochemistry (IHC) staining.MethodsThis study involved 104 cases of gastric biopsies that were previously subjected to WS staining. All cases involved retrieval of formalin-fixed paraffin-embedded (FFPE) gastric biopsies that were re-cut, subjected to anti-H. pylori IHC staining and reviewed blindly by a pathologist. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of WS as compared to IHC were calculated.ResultsIn this study, WS stain was less sensitive in detecting H. pylori. The sensitivity, specificity, PPV and NPV for WS stain were 50.0%, 92.4%, 79.2% and 76.3%, respectively.ConclusionsThe sensitivity of WS stain in the histopathology laboratory was lower than that described previously. Several external factors that might influence the results were identified. However, sufficient information on patients’ history of treatment and medication would be required for the diagnosis or confirmation of the presence of H. pylori in gastric biopsies by WS staining.

The Use of Ancillary Stains in the Diagnosis of Barrett Esophagus and Barrett Esophagus-associated Dysplasia: Recommendations From the Rodger C. Haggitt Gastrointestinal Pathology Society.

Barrett esophagus (BE) is a known risk factor for the development of esophageal adenocarcinoma. Pathologists play a critical role in confirming the diagnosis of BE and BE-associated dysplasia. As these diagnoses are not always straightforward on routine hematoxylin and eosin-stained slides, numerous ancillary stains have been used in an attempt to help pathologists confirm the diagnosis. On the basis of an in-depth review of the literature, the Rodger C. Haggitt Gastrointestinal Pathology Society provides recommendations regarding the use of ancillary stains in the diagnosis of BE and BE-associated dysplasia. Because goblet cells are almost always identifiable on routine hematoxylin and eosin-stained sections, there is insufficient evidence to justify reflexive use of Alcian blue (at pH 2.5) and/or periodic-acid Schiff stains on all esophageal biopsies to diagnose BE. In addition, the use of mucin glycoprotein immunostains and markers of intestinal phenotype (CDX2, Das-1, villin, Hep Par 1, and SOX9) are not indicated to aid in the diagnosis of BE at this time. A diagnosis of dysplasia in BE remains a morphologic diagnosis, and hence, ancillary stains are not recommended for diagnosing dysplasia. Although p53 is a promising marker for identifying high-risk BE patients, it is not recommended for routine use at present; additional studies are needed to address questions regarding case selection, interpretation, integration with morphologic diagnosis, and impact on clinical outcome. We hope that this review and our recommendations will provide helpful information to pathologists, gastroenterologists, and others involved in the evaluation of patients with BE and BE-associated dysplasia.

Challenges in Diagnosing Medication Resins in Surgical Pathology Specimens: A Crystal-Clear Review Guide.

- Medication resins, including Kayexalate, sevelamer, and bile acid sequestrants, can be encountered in gastrointestinal tract specimens. Their classic histologic appearances have been well documented, but pathologist recognition of the resins is 75%, patient history is not always available, and atypical morphologic findings are sometimes present. - To offer a succinct overview of resins in the gastrointestinal tract, including typical and atypical appearances, in order to serve as a quick reference guide. - The study comprises published literature, survey data, and our personal experiences. - Classic morphology is the benchmark for identifying these resins, but color, location, and fish scale pattern can deviate from the norm, making proper identification a challenge. Patient history should be sought whenever possible, and ancillary staining is an option when necessary. Additionally, the presence of resins should prompt the pathologist to search for potentially related diagnoses (namely, causes of diarrhea in patients on bile acid sequestrants and diagnoses associated with renal failure in patients on Kayexalate or sevelamer).

Prospective identification of Helicobacter pylori in routine gastric biopsies without reflex ancillary stains is cost-efficient for our health care system

Despite the recommendation of expert gastrointestinal pathologists, private and academic centers (including our own) have continued to use ancillary stains for identification of Helicobacter pylori. For a 1-month period, gastric biopsies were prospectively evaluated for H pylori using routine hematoxylin and eosin (H&E) and a reflex Diff-Quik stain. During this time, 379 gastric biopsies were collected on 326 patients. H pylori organisms were prospectively identified in 23 (7%) patients, all of whom had superficial dense lymphoplasmacytic inflammation expanding the lamina propria. An additional 2 patients with neutrophilic inflammation were found to have H pylori by immunohistochemical staining. One patient diagnosed as having normal gastric mucosa was retrospectively found to have inflammation with rare H pylori organisms originally overlooked on both H&E and Diff-Quik but later identified on immunostain (0.5%). No patients with chemical gastritis (16%) or chronic inflammation (27%) were found to have H pylori. During the study month, 9 immunostains for H pylori were performed in addition to the 379 Diff-Quik. After discontinuation of reflex Diff-Quik, approximately 20 immunostains are performed for H pylori each month, which decreases technical time spent for processing gastric biopsies and reduces cost to the health care system. In our population with a low prevalence of H pylori, reflex staining for organisms is not cost-effective. The organisms can be seen on routine H&E; when suspicious superficial or active inflammation is present without visible organisms, immunohistochemical stains will confirm presence or absence within a day. Discontinuation of up-front ancillary studies is cost-effective without compromising patient care.

Histological identification ofH. pyloristained by hematoxylin-eosin and Giemsa: review for quality control

Introduction: Several special staining methods are available for H. pylori (Hp) identification in histological sections of chronic gastritis (CG), including the routine hematoxylin-eosin (HE) method. Some reports suggest that ancillary stains are not always needed to establish the diagnosis of Hp infection. In addition, the benefit of using them, when biopsies show minimal inflammation, is not clear. Objective: We performed a retrospective study to compare the usefulness of HE with Giemsa method for the histopathological diagnosis of Hp in tissue sections. Methods: Histological sections from 390 consecutive patients were reviewed. The patients were registered in the histopathology laboratory of Instituto Alfa de Gastroenterologia, Hospital das Clinicas da Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brasil. They were divided in 4 groups according to the gastric inflammatory changes as follows: Group I, gastric mucosa with normal morphology or minimal inflammatory changes (n = 146); Group II, chronic gastritis (CG) with mild inflammatory activity (n = 101); Group III, CG with patent inflammatory activity (n = 123); Group IV, patients with atrophic body gastritis (n = 20). All histological sections were carefully evaluated by 2 examiners at the oil immersion objective (1000×). Results: The identification of Hp was positive by Giemsa and HE, respectively at: Group III, 111 (90.2%) and 93 (75.6%) patients (p < 0.01); Group II, 43 (42.6%) and 29 (28.7%) patients (p < 0.05). Hp was negative in Groups I and IV. Conclusion: The results show that Giemsa stain is superior to HE for histological identification of Hp in CG. Although Hp could be identified by HE stain in the majority of CG cases, a significant number of infected patients may be neglected, regardless the intensity of the inflammatory response.

Upfront special staining for Helicobacter pylori in gastric biopsy specimens is not indicated.

The practice of routine upfront use of special stains in biopsy specimens with minimal or no inflammation has not been evaluated. This study was conducted to determine the value of special stains for Helicobacter pylori in gastric biopsy specimens showing variable degrees of inflammation and to evaluate the practice of upfront ancillary staining of all mucosal biopsy specimens. Immunohistochemical or Diff-Quik stains were done on sections of 570 gastric biopsy specimens. The rates of positivity for H pylori were calculated in each category based on the degree of inflammation and classified as normal, minimal, mild, moderate, or severe. H pylori was not detected in 386 (67.7%) biopsy specimens that were classified as normal (6.0%) or with minimal inflammation (28.2%) or mild inactive gastritis (33.5%). The organism was identified by Diff-Quik or immunohistochemical stain in 76 (89.4%) of 85 with moderate active gastritis and 30 (93.8%) of 32 biopsy specimens showing severe active gastritis. Upfront staining of gastric biopsy specimens is not cost-effective since a significant proportion of the gastric biopsy specimens were normal or showed minimal inflammation; in none of these biopsy specimens was the organism found. Special stains should be performed only in selected biopsy specimens that reveal any degree of chronic active gastritis or moderate inactive gastritis.